Veterinary laboratory tests, part 1

Our pets and farm animals get checked by the vet every once in a while. Often the vet needs a sample to test. For us owners the samples are usually classified by the substance needed: there are blood test, tests from urine samples, test from stool samples etc. It's easy to understand and definitely clear enough for everyone involved.

Veterinarians and laboratories, however, use a bit different kind of classification. For their purposes it provides more clarity. Some common types of tests are 

• Hematology
• Chemistry
• Urinalysis
• Cytology and histology

Tests are often run in "panels", meaning a group of tests which are often requested together. Instead of separately requesting for a test for all liver-related values, for example, the vet can just order a "liver panel". The panels available differ per laboratory and testing company.  

Hematology

Hematology tests the different cells in the blood. It studies the life cycle, form and size (morphological features) and the amounts of these cells.  The blood to be sampled is submitted either in a test tube or as a smear on a glass. The sample should be as fresh as possible to avoid lysis (cells breaking down) and clotting. If the sample is shipped to an external laboratory correct packaging and shipping are vital to preserve the sample in good quality. 

The tests are further classified by what cells are being studied. Red blood cells, white blood cells and platelets all have their own functions in the body. For red blood cells we can for example test for hematocrit (HCT), which is calculated from the amount of red blood cells and the mean cell volume. We can also calculate reticulocyte percentage to see how much of the red blood cells are immature. A high number of immature cells could indicate blood loss by bleeding or cell death. 

For white blood cells we calculate the total number, morphology and percentage of different types of white blood cells. The changes in these cells form a leukogram. 

Platelets help the blood clot, and are the third type of cells used in hematological tests. Similarly to red and white cells, we count the number and percentage of platelets. We can also determine their morphology. Too many platelets is called thrombocytosis (increased clotting risk), and not enough platelets is called thrombocytopenia (blood is not clotting properly). 

Chemistry

Chemistry tests urine or blood, but in a different way than hematology. These tests can be called clinical chemisty, clinical pathology of blood chemistry. Unlike hematology, chemistry is tested most often from serum or plasma. Serum and plasma are acquired by removing the cells from the blood sample. If the blood is left to clot,  serum remains. If the clotting is prevented with anticoagulant, the result is plasma. 

(c) mouseserum.com

Some examples of chemistry tests are electrolytes, minerals and kidney function.

Electrolytes help cells to function properly. They are carefully regulated, and any deviations can point to a health concern. Sodium concentration can be measured to estimate the the amount of fluids in the body (dehydration). Potassium is crucial to the correct working of muscles. Minerals like calcium and magnesium can reveal organ failure (the body will get lacking minerals from internal organs) or muscle weakness due to lack of calcium (milk fever in cows being a well-known example).   

To estimate kidney function a chemistry test measuring creatinine or urea nitrogen can be done. 

Urinalysis

Urinalysis is the analysis of urine. It focuses on describing the urine (color, cloudiness) and looking at the bacteria and biochemical properties (such as protein, blood and pH). All of these values describe the functioning of the kidneys and urinary tract. 

Much of basic urinalysis can be done at a clinic using a simple dipstick. It's a stick with several pads, which is dipped into the urine. Each pad reacts to a specific substance in the urine. Looking at the colors of the pads the nurse or vet can determine the basic properties of urine. 

 

Sensitization and habituation

Sensitization and habituation are two essential terms when it comes to animal research. They describe the way animals' reactions change to a specific stimuli over time. After every time a stimulus is met, learning occurs. The animal is changed through the experience, and these changes lead to a more profound, noticeable change if the stimulus is repeated. 

Sensitization happens when after repeated occurrences, usually with a lot of time in between them, an animal starts to react more strongly to a stimulus. Their reaction may be more pronounced, and the physiological measurements (blood pressure for one) can be more extreme than before. Examples of sensitization:

• Repeating unpleasant handling. Animal learns that the experience is painful, and can start reacting even stronger every time. (for humans this can be the case with dentist's appointments).
• Loud, sudden sounds like fireworks on New Year's Eve. A dog may not react to the first bangs, but as they keep repeating on uneven intervals, the dog starts reacting more and more strongly during the evening and night. 
• Traumatic event, which leads to fear of smells, sights or other items that coincided with the place of the original event. 

Sensitization usually does not last for very long. The stronger the stimulus, the longer the sensitization lasts. Makes sense, doesn't it - after a quiet "pop!" we're jumpy for a while, but after the bang of explosion the jitters are considerably worse!

Sensitization is not very specific to a stimulus. An unpleasant experience at the veterinarian can cause sensitization towards the vet, but also towards people with similar clothes, the physical location or the smells that were present.  

(c) https://www.dreamstime.com/

Habituation is the opposite of sensitization. According to Lumen Learning, "Habituation occurs when we learn not to respond to a stimulus that is presented repeatedly without change, punishment, or reward". Something happens, but nothing follows from it - therefore it's not needed to react to this stimulus. Broom uses an example where a flock of sheep is moved from a quiet pasture to a field next to a road. At first, they will react to every passing car. As the cars keep on driving by, they get used to it and react less and less. You could say they got bored of the cars, which is in a sense correct. The more scientific terms is that they've habituated.

Other examples of habituation are

• Habituation to humans and human touch
• Habituation to light-dark rhythm.

Habituation is very stimulus-specific. An animal might habituate to a specific type of noise, but if it changes in volume, pitch or sound, the animal will react to it again. In our example the sheep might ignore a car, but react strongly to a Harley-Davidson.

Habituation rely heavily on repetition. Factors influencing the result are regularity (how often does the event repeat), pattern (does it repeat in an predictable interval) and time between repetitions. For example, animals habituate quickly to stimulus repeating often in a short time. However, the recovery (when the habituation wears off) is also quick.

 

More on habituation and sensitization

Biological Basis of Learning | Boundless Psychology (lumenlearning.com)

Microsoft PowerPoint - Learning.ppt (ucsd.edu)

 

Behavioural modeling

There you are, looking for a job, and one of the requirements is "experience in behavioural modeling".  What does that actually mean? 

The first thing to determine is what are behaviours.  Behaviours, or behaviors for the Americans among us, are easily understood but harder to define. Purely based on the linguistic definition, Oxford Languages says they are "the way in which one acts or conducts oneself, especially towards others" but also "the way in which an animal or person behaves in response to a particular situation or stimulus." Lee Alan Dugatkin agrees with the latter, formulating that "behavior is the coordinated responses of whole living organisms to internal and/or external stimuli." A behavior happens where there is a need "If an animal has a need, its motivational state is affected so that behavioral and physiological responses that should result in remedying that need can be made." (D. M. Broom).

It seems to me that behaviors are coordinated movements and acts, directed to addressing a need. Some behaviors are learned (styles of playing, replies to human commands), and some are inherited (searching for a teat after birth). 

Now that we know about behaviors, let's see what are models? Modeling means to build models, abstract representations of complex truths. A model can be a simplification, and can fit to all instances of a repeating concept. A model can be used to compare representations across species or in time.  Schank, Joshi and May write that "Models can be physical, symbolic, mathematical, or computational, but they are always simpler than the animal systems they represent." Clearly then there are several methods of modelling, and the best fit can be chosen based on the goal of the research. If we intend to use behavioral data in a computer system, a mathematical or computational description would seem the most suitable. If we intend to demonstrate the behavior to others or even mimic it, physical modelling is the way to go.  

Schank et. al. also give models nine dimensions:

1. Realism
2. Detail
3. Generality
4. Match
5. Precision: how quantitatively precise a model is in it's predictions  
6. Tractability: how analyzable or manipulable a model is
7. Integration: Can it be used together with other models?
8. Level: Cellular, population, strain...
9. Medium

Let's take a look at some models to better understand how they really could look like.  The first example is a hidden Markov model (HMM) from the publication of Leos-Barajas, Gangloff, Adam et. al (2017).  This is a mathematical model. It looks complicated, and will require understanding about the mathematical notation and statistics to understand and to apply. 

Another beautiful example is from Ellen Evers from the University of Utrecht. In her presentation she explains the differences of Agent-based models (ABM) and Ordinary differential equations (ODE). 

An ABM looks at individuals: how each individual moves and acts during the behavior. It is less effective in modeling the group. An ODE looks at a group and determines the behavior of the group as a whole, losing sight of each individual. Her example uses the balance of wolves and sheep. Sheep are increased by births, and decreased by predation by wolves. Wolves are increased by predation, and decreased by natural death. 

In ODE terms the  models are

Sheep = + birth*Sheep – pred.*Sheep*Wolves  

Wolves = + pred.*Sheep*Wolves – death*Wolves

But for ABM the rules are for each individual:

SHEEP: If I meet wolve: die!

With chance = birthrate: Reproduce!

WOLVES: If I meet sheep: energy +1

If energy (from sheep) = 0: die!

With chance = birthrate: Reproduce

The big difference is that ODE model is deterministic. It can be used to predict situations when some variables are known. It could change what happens when there are 100 wolves and 50 sheep in comparison to a situation with 100 sheep and 50 wolves (in both cases, it's not looking good for the sheep.) ODE is not spatial (measuring things in terms of movements in space) and requires homogenity. ABM, on the other hand, just models the situation. It is applicable to heterogenous populations. 

I hope that this short introduction has given you some insight into modeling animal behavior. It is a complex field, and the lesson from Ellen Evers is heartily recommended as a good starting point for understand the differences of ABM and ODE.

More information

Lee Alan Dugatkin: What is "behavior", anyway?

D. M. Broom Animal welfare: concepts and measurement

Schank, Joshi, May et. al. Multi-modeling approach

Leos-Barajas, Gangloff, Adam et. al: Multi-scale modeling of animal movement and general behavior data using Hidden Markov models with hierarchical structures

Ellen Evers: ABM and ODE

Types of animal welfare studies

 When talking about animal experiments, it's easy to start thinking along the lines of mice, needles and electric shocks. But there are naturally a lot of other kinds of experiments as well. Consider a simple case where an animal is offered two kinds of food to see which one they choose first. That is also research on animals!

The study of animal welfare is a very complex field. Just to start with: what IS welfare and how to measure it when the animal itself cannot talk or describe it's emotional states? Obviously a complicated set of research methodologies is needed to achieve robust results. The measurements taken to achieve the results can be roughly divided into two: physiological and behavioral.

Physiological	Behavioral
Temperature Heart rate Blood glucose Fat percentage Weight Bacterial count	Time spent sleeping Frequency of a specific behavior Posture changes Social contacts Time taken to approach objects Distance traveled to forage

As you can see, welfare can actually be quite specific!

Next, let's have a look at some types of studies which are conducted to find out more about animal welfare. All of the measurements listed above are just data, but it's of course important to know how to gather the data to make sure - you guessed it - that the data is correct. So what kind of experiments are used?

Preference studies

Preference and motivation studies are both examples of empirical study, where the researcher gathers data on the target of their study. In preference studies the animals choose what they prefer and what factors influence the preference.

An example of preference study is to offer chickens feed with and without NSAIDs (painkillers). Chickens with healthy feet eat more of the feed without medication, while chickens with leg sores and ulcerations prefer the feed with the medication (self-medication). Factors affecting the preferences can be available time, diet, health and pregnancy.  

(c) Louse Buckley, UFAW

Motivation studies

Motivation study measures the motivation or willingness of an animal to reach a specific goal. The aim is to find out the value of things  and what impacts the motivation. For example, an animal might be very motivated to get a treat when alone, but less motivated when they're in a group and know they might need to share their treat. Measurements can be speed and distance traveled to the goal,  latency before the animal tries to reach the goal and energy spent to reach the goal.

In classic examples animal can be trained to press a lever to get a specific treat. Then the treat is disabled, and the amount of times the animal presses the lever trying to get the treat is the "price" they're willing to pay for it. Things like temperature, eating, health and group size can all affect the value of the reward. 

Metastudy

Metastudy is different from the other types, because this is the study of studies. In metastudies the researchers gather a vast amount of previous researches, carefully select the most relevant ones and summarize their findings. The process of selection and omission must naturally be well documented and argumented. The aim is to see wider trends and generalizations. Commonly seen phrases like "many studies prove" or "there is little scientific base on the claim that" arise from metastudies. Metastudy goes further than just being a literature review. It uses for example statistical methods to compare the results of the studies once comparativeness is established.   

More information:

Animal welfare science - Wikipedia

Consumer demand tests (animals) - Wikipedia

Fur farming - breeding and welfare

When talking about animal breeding, it is important to understand what it is. Breeding aims at improving the genetics of an animal population with methological breeding systems and programs. Breeding has clear targets, traits to be measured, recorded and followed etc. Breeding is not about increasing the animal population by mating animals to one another, which is what some pet "breeders" do.

Colors of mink pelts (c) Fur Commission

Fur animal breeding has always aimed at producing pelts which fetch the highest price in the market. Three main qualities affect the price: the size, quality and color of the pelt. Size is measured as the length of the pelt. As a breeding target larger pelts require larger animals, so often the largest and the ones that grow fastest are selected as breeding animals. Large in this context means fat. This however has lead to severe problems with fertility: fat females give birth to small litters. Fur animals breeders must therefore balance between size and litter size to produce enough pelts of an adequate size.

Pelt quality consists of several traits. The most important quality factors are

• flaws (such as bite marks)
• the quality of the guard hairs
• the quality of the undercoat

The quality of the pelt is a combination of its mass and the coverage of the guard hairs. The ratio between guard hairs and undercoat contributes to the mass of the pelt. In a pelt of good mass the undercoat is thick, strong and elastic, and it supports the guard hairs. In a high quality pelt the guard hairs are longer than the undercoat, there are no color flaws and the length of the hairs is even.

The third important quality factor is the color of the pelt. The desirability of different colors varies yearly and depends on fashion trends. Color can be determined by several qualities, such as hue and darkness.

Breeding traits

The breeding objectives can be divided to three classes, all of which may or may not be used for all fur animal species. The targets are evaluated in a two-step process, first in grading and then as pelt quality factors.

Grading is a process where the quality and color of the fur of live animals is manually estimated. Four qualities are estimated: the size, color, purity and quality of the pelt. Grading is done at the fur farm, and may be done several times a year. The size of the pelt is either estimated or measured. Pelt size is measured from the tip of the nose to the beginning of the tail. The purity of the color is also evaluated. For blue foxes the pelt can have four hues ranging from blue to red. The darkness of the color is graded and the mass of the pelt is estimated.

Mink pelts at an auction (c) Searching for Style

The same traits are measured again after skinning in a process called evaluation of the pelt quality. The differences are that pelt quality evaluation is done post-mortem and usually automatically, while grading is done when the fur isn't yet fully developed and is a manual task. The number of classes to which pelts are classified also varies between grading and pelt quality evaluation. For example in grading the pelt quality gets a score from 1-5, while the pelt quality classes depend on the company selling the pelts.  There are six traits evaluated as pelt quality: grading qualities (the size, color, purity and quality of the pelt) plus mass and coverage of guard hair.


Fertility is probably the most important breeding target. There are two main fertility traits:

• Litter size = number of puppies alive at 3 weeks of age / number of dams with at least one 3wk old pup
• Litter result = number of puppies alive at 3 weeks of age / number of mated females

The litter size and result are counted after the pups are three weeks old, because the highest pup mortality is during the first weeks of life. Studies show that young blue fox dams produce larger litters, but the pups have higher mortality than the pups of older females. 2 year old blue fox vixens have the best litter results.

Heritabilities (h²) and genetic correlations in blue foxes

Heritabilities are a way of measuring how much genes impact a certain trait, i.e. how well can the trait be developed by animal breeding. Traits with high heritability are easier to develop than traits with very low heritability. Heritability ranges from 0 to 1, where 0 means that genes have nothing to do with the trait, and 1 means that the trait is affected by genes only and there's no environmental impact at all.

A Finnish doctor of animal science, Jussi Peura, has calculated heritabilities to several breeding traits for the blue foxes. He found that pelt traits have the highest heritabilities and fertility traits have the lowest. For example, color darkness has a heritability of 0.55 and pelt size 0.30. On the other hand, litter size at 1st parity (1st litter) had a heritability of 0,1, which is fairy low.

Litter of silver foxes (c) Bioacoustica

Peura also studies genetic correlations, i.e. how much traits depend on other traits. For example, in humans height often correlates with weight: the taller, the heavier. For blue foxes there were clear positive genetic correlations between size in grading and size in pelt quality (0,74), color in grading and pelt quality (0,84) and quality in pelt quality and mass in grading (0,75). When a correlation is positive, both traits increase simultaneously.

Negative correlations mean that increasing one trait decreases the other. Blue foxes had a significant negative correlation between size and litter size (-0,28). There were mild negative correlations also between size and color purity in grading (-0,25) and color in pelt quality and size in grading (-0,17).

What all these mean is that grading gives a reliable estimation of the actual size and quality of the pelt. However, the purity estimation in grading is a poor estimation of the actual purity. The correlations also clearly show that increasing the size of the animals result in poor litter results.

Welfare of fur animals

The issues and solutions presented in this text are based on WelFur, which is again based on WelfareQuality -protocol. Welfare issues here are classified under the four basic principles of WelfareQuality: good feeding, good housing, good health and appropriate behavior.

Animal welfare is a complicated concept with several different definitions and theories. Here animal welfare means the subjective experience the animal has about its own psychological and physiological state as the animal tries to adapt to its surroundings. Welfare cannot then be measured directly. Animal cannot have a welfare of "9.5" or "good" - we can merely measure its behavior and surroundings, and deduce the level of welfare from the findings.

Good feeding

Body condition score for blue foxes

As has been previously discussed, obesity is a severe problem for blue foxes. They naturally would eat a lot during fall, and show this behavior also in fur farms. In farms feed is easily available and high in energy, so the animals gain weight very fast, and the size of their pelt increases. Obesity causes their front paws to bend, which again makes mobility very difficult. Healthy paws are rare in any blue fox farm.

Fat animals cannot breed well, so the animals kept alive for breeding are nearly starved during the winter. While it would be natural for them to lose weight, in farms the difference between the Fall weight and Spring weight is much greater than in the wild. Normally a blue fox would weigh 3-5 kg - the average weight of farmed blue fox males is a staggering 19 kg, and 10 kg for the females.

In any farm where animals are kept in group cages there is no peace during feeding. The animals fight over the food, which causes stress, and fearful animals may be underfed while the more dominating animals are overfed.

Another problem common to all fur farms is the availability of fresh, clean water. During winter the water pipes may freeze, and during summer the water may heat and become unsanitary. Problems with availability of water are usually technical in nature: unlike with feeding, there is no reason to purposefully limit the animals' intake of water.

Good housing

Good housing is a wide concept, which consists of a comfortable place to lie, warmth and the easiness of mobility.

Foxes on a shelf (c) Dyrevern Alliansen

Small fur animals, like minks and ferrets, must have a nest box available all year round. Foxes have a nest only during whelping. The nest is the only part of the cage with solid floor and walls: otherwise the animals sleep, play and walk on a metal net ( = mesh). The nest box has been proven to increase fearfulness towards humans, because it gives a place for the animals to hide to. That, and the animals' tendency to defecate on solid surfaces, are the main reasons for keeping the nest box available only for a short while. 

Foxes must also have a shelf in their cage, unless they can lie on top of the nest.The shelf is actually very important for the foxes, who prefer high places from where they can scan their surroundings.

The main reason for using mesh flooring is that urine and feces pass through it. Fur animals have a tendency to defecate on a solid surface, which would then need to be cleaned daily to prevent the animals from soiling their fur. While a mesh floor sounds unpleasant, foxes actually prefer mesh over earth floor or solid floor such as wood at least as a resting place. This may be because the mesh allows their fur to stay "puffy" so the animal stays warm. There are no similar studies done on other fur animal species.

Good health

In order to have and to maintain good health, the animals must have good housing and good feeding. Good health means that the animals have no sicknesses, but also no internal or external injuries or disabilities. In fur farms mortality due to diseases is somewhat low, 3-4 % in foxes between April - October. Treatment of illnesses may be rare. Many animals are kept until skinning even if they are sick, or left to die.


Disease epidemics in fur farms are relatively rare. The only exception is plasmasytosis for minks, which occasionally causes significant losses due to sickness and exterminations. The most common diseases vary between animal species. For foxes and minks infections of the womb and gut are the most common illnesses. Eye and skin infections, urinary tract infections and diarrhea are sometimes seen in foxes. Diarrhea can also infect minks, but rarely raccoon dogs, who are capable of eating even partially rotten meat without trouble.

As has been noted before, bent front paws and obesity are extremely common health risks in blue foxes. They are not usually life-threatening or even painful in fur farm conditions, but most likely they do decrease the animal's welfare.

Compared to most farm animals (cows, pigs etc.) fur animals receive no painful treatments. For example, there are no surgical castrations, tooth cutting or cutting of the ears, which are all performed on piglets. Still, care must be taken to ensure that all fur animals are killed humanely and quickly before skinning. The killing and skinning must be done far away from the live animals to prevent fear and panic.

 Appropriate behavior

Expressing normal and appropriate behavior is mostly impossible in fur farms. Pups can be weaned at the "correct" age, but they cannot spread apart like they would do in the wild. Animals are not allowed a space for their own. They also do not need to hunt or forage, which in the wild would occupy most of their time.

Silver foxes would normally live in small groups, where only the dominant female would raise a litter, and the females of lower rank would kill their own pups if they have any. To keep thousands of females in adjacent cages, all with their own litter, may cause stress and increase situations where females kill their pups.

Group vs single housing is an important question for all fur animals, but many study results are contradictory. Group housed minks can fight more and therefore damage the pelts. Their stress levels may also be elevated if the group is not balanced. On the other hand, group housed minks have company, can play with one another, and in a balanced group are also less stressed than individually housed animals.

Fur farming - animal species and annual cycle

Fur animals are farmed to provide raw material for clothes designers and the fashion industry. The ethics of fur farming is an important topic and should always be considered, but it will not be covered here. This post is about the practices of fur farming, fur animal species and caring for fur animals.

Every year nearly 60 000 000 mink pelts and 4 000 000 fox pelts are produced, with Denmark as the leading producer of mink pelts (over 15 million annually) and Finland of fox pelts (nearly 2 million). When these numbers are considered, it is obvious that fur farming is important to the national economy to some countries. Still, major fur producing countries like the Netherlands have banned fur farming due to ethical concerns. Finland's house of parliament voted on the subject in 2012, and vetoed a bill demanding to end fur farming.

Fur animal species

Mink (Neovison vison)
Minks are the smallest of fur animals, weighing 1-4 kgs and ranging from black to brown to white in color. Minks, like all fur animal species, come to heat once in a year in the spring. Female minks are in heat during the beginning of March. Mating induced ovulation, so the mating time does not need to be carefully planned, and usually each female is mated 2-3 times. One male is allowed to mate with 4-5 females.

The gestation period for minks is 40-70 days. Most minks in one farm have their litter within 2 weeks from each other. Naturally minks would deliver 6-7 pups, but in captivity only 4-5 pups survive to adulthood. Minks are killed with gas (CO / CO₂) and skinned in November, apart from breeding animals which are kept over the winter and mated again in Spring.

Minks are raised either alone, or two or four animals in one cage. Studies show that group housing reduces stereotypical behavior, but only if the groups are kept steady and balanced. Usually groups consist of pups from the same litter, with one female and one male, or two of both. In Europe, four pups or 2 adult animals may be kept in a cage of 2550cm² in size. In the wild each mink would live alone in a territory covering several hectares.

(c) greengirlabroad

Blue fox (Vulpes lagopus)
The blue fox originates from the endangered arctic fox. Its weight ranges from 8-12 kg, but the largest males can be near 19 kgs. The largest animals are not muscular but obese: foxes are overfed to make them fat, which increases the size, and thus the price, of the pelt.

Obese animals suffer from major health issues, such as bent legs and difficulty to move. In recent studies in Finland, blue foxes with healthy legs are a rarity. Because fat animals breed poorly, the animals kept for breeding are kept on minimum food during the winter, so they lose weight and are able to breed in the Spring. While it mimics the natural habit of the animals (gathering body fat in the fall for the harsh winter), in farms it is taken into extremes and thus causes major stress for the animals.

Blue fox females, vixens, are in heat for 4-5 days during February and March. Most vixens are artificially inseminated using sperm collected from male foxes in the same farm. The gestation lasts 51-53 days, and each litter has 5-7 pups. This is a very poor result compared to the litter size of wild arctic foxes, which is 8-10 pups.

Blue foxes have a very thick fur to keep them warm. Because on solid surface the fur would flatten, the animals actually prefer net flooring to solid flooring. Still, overgrown claws and wounded paws may occur even if the net is covered with plastic.

(c) Wikimedia commons

Silver fox (Vulpes vulpes)
Silver foxes are descendants of the common red fox. They are smaller and leaner compared to the blue fox, and their fur is less thick. Silver foxes are not fattened and then starved like blue foxes, because due to their heritage they are more finicky eaters.

Silver foxes are in heat for 2-3 days during January-April, and deliver litters of 3 pups after 51-53 days of gestation. In the wild the litters have 4-5 pups. Artificial insemination is rarely used, and one male mates with 4-5 females. Breeding blue and silver females are kept in the farms for approximately 5 years, after which they too are killed and skinned.

In Europe silver foxes are raised in cages of two, or a female with her pups.The cages have a nest during whelping, and a shelf to provide a "solitary" place where the animal can watch its surroundings. Foxes want to see what happens around them, which is why they are often raised in a "shadow house" with free visibility to every direction.

(c) PeTA Asia-Pacific

Raccoon dog (Nyctereutes procuonoides)
Raccoon dogs weigh from 5-15 kgs, and come to heat for 3-4 weeks during February-April. Like with silver foxes, each raccoon dog male mates with 4-5 females. The gestation period is 60 days, after which a litter of approximately 6 pups is born. In the wild litters have 6-12 pups.

Raccoon dogs are monogamic: in the wild they form life-long partnerships, and both parents tend to the pups together. In fur farms this kind of behavior is entirely denied, and each female has to tend to her pups alone. On the other hand the farmed female doesn't need to hunt her food, and therefore doesn't have to leave the pups to go foraging. It is not known whether raccoon dogs should be farmed in pairs to improve their welfare.

(c) CBS Minnesota

Ferret (Mustela putorious)
Ferrets are possibly the least farmed species, even though they can have up to two litters of 6 pups in one summer. In the wild each litter would have 2-17 pups, so the ferret is the only farmed animal whose litter size in captivity is not markedly smalled than in the wild. Ferrets come to heat in April and gestate for 42 days. The second heat occurs two weeks after the first pups are weaned.

While these are the same animals than the ferrets kept as pets, farmed animals receive none of the caring of pets. They are raised in small cages, bred, weaned, killed and skinned like all other fur animals. The instructions and laws regarding pet ferrets do not apply for their farmed counterparts.

The annual cycle of fur farms

Each year in a fur farm can be divided into six phases, regardless of the farmed animal species. Each year follows the same pattern: mating in early Spring, whelping during Spring and early Summer, and raising of the whelps and separating them into their own cages during Fall. Selecting breeding animals and killing and skinning the rest takes place in early Winter, after which the breeding animals are "kept alive" until they can again be mated in Spring.

Healthcare of poultry

Vaccinating hens against H5N1. (c) Reuters

To understand healthcare of poultry, one must first understand the conditions in a poultry house. Apart from organic production, there are no limits to how many animals can be kept in one hall. Meat chickens and layers are reared in flocks of  10 000 - 40 000 or higher. Turkey and goose flocks are usually  smaller. It is easy to comprehend that medication and health checks are flock-based: it is impossible to monitor and care for each individual animal, even though their pains and problems are unique. Therefore a disease outbreak is often noticed as the production or growth of the entire flock are decreased.

Viruses and parasites spread nearly immediately to every bird in the flock. If there are several poultry farms in a small area, the disease can spread from one farm to another in car tires, boots, dirty hands, clothing, by wind etc. "Backyard hens" and wildlife are also a risk to commercial poultry producers. Disease control, preventive medication and quarantines are vital in animal import/export. As the bird influenza -epidemics have shown, international and even global disease outbreaks are possible, and carry heavy consequences to poultry and, in extreme causes, to humans as well.

Each poultry keeper should take and send samples to an official laboratory for disease screening. Easy and quick methods of taking samples are

• Shoe cover sample: Put on dispensable shoe covers, and walk amongst the floor-reared birds. Swap the covers between different sections of the hall. Send the individually-packed dirty covers for screening.
• Feces sample: Mix an adequate amount (100-200g) of feces from all feces collector mats or different parts of the poultry house.
• Incubation sample: Mix 100-200g of broken egg-shells and floor litter from the incubator
• Dust and swab samples: Take and store individual samples from all around the poultry house: floors, corners, feed trays etc.

(c) The Poultry Guide

All diseases are cheaper to prevent than to cure. Most diseases lower production, and may lead to eggs or carcasses being rejected entirely, which decreases profits and increases costs as decreased feed utilization rate and medical costs.  The steps for disease prevention are simple:

• Allow only necessary guests to the poultry house. 
• Ensure all visitors wear disposable shoe covers and other protective clothing provided by the farm.
• Ensure no one enters the poultry house if they've been abroad during the last 48 hours.
• Follow the official and recommended vaccination and medication programmes.
• Monitor the animals and production levels closely.
• Repel indects, flies, rats and other vermin. Ensure wild birds cannot enter the poultry house or feed storage through air ducts or ventilation shafts.
• Use barriers. Make sure all clothing and equipment used in the poultry house is kept there, and all "dirty" clothes and tools are left in the barrier area. 
• Follow the all-in, all-out method with thorough cleaning and disinfection between flocks.

Common diseases

Salmonellosis
Several bacterial strains can cause salmonellosis. Salmonella Enteritidis and S. Typhimurium can infect poultry and humans alike. Both bacteria are infectious if swallowed, and are common in eggshells and feces. Infection through infected feed is rare but possible. S. galliarum infects poultry only, and may cause 100% morbidity in birds of any age. It survives months in a normal climate, but is susceptible to disinfectants. S. pullorum infects only poultry aged three weeks or older. 

Symptoms of all types of salmonellosis on poultry are ruffled feathers, closed eyes, diarrhea, loss of appetite and thirst and stunted growth. Post-mortem lesions can occur. Morbidity is low to medium. Salmonella can be cured with antibiotics, which are added to the feed or drinking water. The meat of infected birds may be accepted for normal food processing after heat processing.

Infectious bronchitis, IB
Poultry can and should be vaccinated against IB. IB is caused by a Coronavirus, which evolves rapidly but infects only chickens. The symptoms depend on the age of the chicken. Chicks get flu-like symptoms. Their oviducts are damaged, preventing them from laying eggs later on. Young chickens show only mild symptoms. Adults have respiratory problems, their productivity decreases and their eggs have faulty shells. Some Corona-strains cause damage to kidneys. IB infection lasts 2-8 weeks. Post-mortem lesions can occur. Morbidity is 0-25 %.

IB can be treated with sodium salicylate. Antibiotics are often needed to treat secondary infections by E. coli.

Skin hemorrhage (c) CFSPH

Newcastle disease, ND
ND is caused by some strains of paramyxovirus. In the EU, ND-infections must be confirmed in a reference laboratory in England. The viruses are extremely resistant: it can live months in feces, weeks in carcasses and years in a freezer.  ND infects all birds. If an ND-infection is confirmed, a stamp-out may be ordered and all poultry within 3 kilometers must immediately be destroyed.

The symptoms of ND vary, but common ones are decrease of production, moulting, hemorrhage of the comb, skin and eyelids, respiratory problems, paralysis and sudden deaths. There is no cure for Newcastle Disease.

Typical posture for a hen with MD.
(c) Poultry Club SA

Marek disease (MD)
Marek is caused by a herpesvirus. It is transmitted as aerosols via respiration, and may infect all animals in a flock in a short time. The virus proliferates in the roots of the feathers, and is extremely resistant. Many healthy birds carry and spread the virus. Marek infects mostly hens, but the symptoms and susceptibility to infection depend on many factors. Most infected are aged 4 weeks or older, most commonly 9-24 weeks of age.

Symptoms include staggering walk, paralysis, dangling wings, enlarged crop, bent neck, respiratory problems, eye deformations and weight loss. Sick birds have normal appetite. There is no cure for MD, and even cured birds will get infected again later.

(c) The Poultry Site

Coccidiosis
Coccidiosis is caused by one-celled parasites of the Eimeria-family. There are nine known contagious Eimeria-species. The infection happens when chickens eat the eggs of the parasite, often brough to the poultry house in contaminated equipment or cargo boxes. The eggs proliferate in the chicken gut, and 4-7 days after the infection there are Eimeria-eggs in the chicken's droppings. The eggs need 1-3 days outside the chicken's body to become contagious. Eimeria infects mostly chickens of 3-6 weeks.

Symptoms are increased mortality, stunted growth, decreased immunity, diarrhea, bloody feces, dehydration and decrease in egg-laying. Coccidiosis can be prevented by adding coccidiostates to the feed, and by keeping the litter clean and dry. The only treatment is keeping the litter clean and treating the secondary infections with antibiotics.

(c) Cornell University

Avian Encephalomyelitis (AE)
AE is a viral disease of the central nervous system, affecting chickens, pheasants, turkeys, and quail. Grandparent, parent and production line birds can be vaccinated against AE. Developing fetuses can get infected by the parent, but oral infections may also occur. Mortality is high.

Symptoms of AE include sitting, paralysis, tremors, imbalance, muscle weakness and dull apprearance. There are no visible lesions in live animals. There is no treatment for AE. 

(c) Science Alert

Gumboro or Infectious bursal disease virus (IBDV)
IBDV attacks the immune system of chickens 14-28 days old, causing severe effects in young birds. It is caused by Birnavirus, and infects chickens, turkeys and ducks. White leghorns are more susceptible to Gumboro than brown breeds. The disease is highly contagious, with mortality of 0-20 %. Gumboro increases susceptibility to all other viral and bacterial diseases, including Newcastle Disease.

Symptoms of IBDV are depression, lack of appetite, diarrhea, hiding and unsteady gate. There is no treatment, but vitamins and water may help. Antibiotic medication may be indicated if secondary bacterial infection occurs. All laying chickens and parents to meat chickens must be vaccinated against Gumboro.

CAV virus (c) ICTV

Blue Wing Disease (BWD) / Chicken Anemia Virus (CAV)
CAV and BWD are different names for the same viral disease caused by Gyrovirus. Mortality is 5-10 %. The virus is very resistant to disinfectants, but is destroyed in 5 minutes in 80 C.

Symptoms of BWD/CAV include poor growth, paleness and a sudden rise in mortality. There is no cure for the disease. Good hygiene and management, and control of other diseases as appropriate, may be beneficial. All parent chickens should be vaccinated 6 weeks before their eggs are collected for incubation.

Evaluation of foot health

Leg deformations, broken bones and infections in the soles of the feet are common welfare problems for fast growing birds all over the world. The birds are bred to grow faster than their bones develop, and to a larger size than their feet can carry. Feet health can be improved by

• Enough dry and clean litter
• Allowing roosting
• Optimizing the ratio of calcium and phosphorus in the feed
• Optimizing the amount of minerals in the feed
• Keeping low animal density
• Allowing locomotion
• Using slow growing breeds  

Foot and leg health can be measured by gait scoring, latency to lie -test or post-mortem from carcasses. In gait scoring, a sample size of 100 birds is selected. Each bird is put in a small enclosure, when the animal is encouraged to walk. The gait is scored from 0-5, and the average of all results is calculated. A score of 0 means a normal gait, 3 is a gait problem affecting the animal's locomotion, and 5 means the animal is not able to walk. Gait scoring is a part of Welfare Quality assessment. In a  Latency to lie (LTL) -test, 2-4 birds are set in a cage with sawdust litter. After 15 minutes, when the birds are relaxed, 3 cm of lukewarm water is poured to the bottom of the cage. The birds will stand up and stay standing as long as possible before falling down to the water. The maximum measured time is 15 minutes. The longer the birds stay standing, the better their score. 100 birds are tested altogether.

Post-mortem examinations are done in slaughterhouses by evaluating the quality of foot soles. This can be done on live animals as well, but may cause unnecessary stress. Same visual evaluations can be done on hocks. Chemical and physical measurements such as tensile strength can also be done post-mortem. The dry matter content and ash composition can be measured from bones. Phosphorus and calcium concentrations in bones can be measured after cremation in a spectrofotometer.

Visual evaluation on foot health. (c) Welfare Quality

Animal welfare in organic production

Directives and settings for organic production in Europe are set by the EU. In addition, each country has their own national laws and decrees, which detail the EU laws. Organic production is a farm management practice, which combines

• production of high-quality food
• respect for animals and their behavioral needs
• eco-friendliness
• sustainability.

Animals are essential in organic production. Growing animal feed diversifies the crop rotation, animals recycle nutrients, promote natural diversity, produce foodstuffs, create income and  tend to the landscape.

Welfare of animals in organic production

A miniature horse treated for leg deformity
(c) University of Pennsylvania

IFOAM has stated that "All management must aim for good animal health and welfare and must be governed by the physiological and basic ethological needs of the animal in question". (Basic standards for organic production and processing, 2002). Preventive health care is the key: producers select the best suitable breeds, feed them with high-quality feed, enabling them with access to outdoors and avoiding too high an animal density. There are strict regulations to the use of medicide for animals, which guarantees that animals are medicated only when needed, not "just in case". However, sick animals are and must be treated accordingly. Veterinarians may prescipt preventive medication, such as deworming. Vaccinations, Phytotherapeutical and homepathic treatments are allowed. Still, any animal must be removed from organic production if they are medicated more than three times a year (if the animal lives longer than 12 months) or more than once (for animals which live less than 12 months).

Some common breeding practices are banned in organic production. Artifial insemination (AI) is allowed, even though it is recommended that all breeding is based on natural methods. Embryo transfer is not allowed, but semen from embryo-transferred bulls may be used in AI. If an animal is bought to an organic production farm, that animal may be embryo transferred.

Allowed and banned animal handling procedures
A capable person may mark a goat, sheep, pig or a cow with ear marks, ear notching, tattooing or with an ID chip. Lambs can be castrated. Piglet canines may be rasped only if they cause problems to the sow, and the problems cannot be solved in another manner. Veterinarians are allowed to castrate goats, horses and cows, but the usage of pain killers is mandatory. Same applies for burning or removal of horns from lambs, goats and calves, and installing a nose ring to a cow or bull.

Producers are not allowed to keep animals chained, although some exceptions apply. Chaining a birthing animal is not allowed under any circumstances. Sows must be kept in groups until the end of pregnancy and during lactation: sow crates are not allowed. Birthing crates are also banned.

Usage of hormones  or other medication to increase growth, fertility or production is strictly forbidden.

Feeding

(c) Sneeuberg

The feeding of cattle, sheep, horses and goats must be based on grazing. 60 % of their daily feed must be roughage, but for the first three months of a cow's lactation period this percentage can be lowered to 50 %. Rearing of anemic animals (for example for production of white veal) is banned.

Feed should be produced on the same farm they are used. 50 % of the feed for herbivore animals must  be endemic. All feed must be organically produced, but in an emergency normal feeds can be used with a special permit.

Feeding of young animals must be mainly milk from their mother or a female of the same species, until the animals are at the age of

• 3 months (cattle and horses)
• 8 weeks (goats)
• 45 days (lambs)
• 40 days (pigs).

Milk powder or other liquid feed can be used only during the 2-year transition phase to organic production, and even then only within limits.

Requirements for animal shelters

Animal shelters for cattle, goats, pigs and sheep must have good, non-slippery flooring, and a maximum of 50 % of the floor may be grated. Resting area must be on solid floor and have litter. All shelters must have windows, which cover an area equivalent to 1/20 of the floor area.

Poultry must have at least 8 hours of darkness in their lighting program, and at least 1/3 of the flooring must be solid (not grated). Broiler chickens must be reared a minimum of 81 days and turkeys for 100 days (females) or 140 days (males). In normal production broilers are slaughtered at the age of ~50 days. Each section of the henhouse may have a maximum of 4800 broilers or 3000 egg-laying hens.
 

(c) mother Earth news

Outing
When national laws don't state otherwise, animals must be able to go out at any time. Harsh weather conditions or low-quality ground are an exception. Maximum of 75 % of the outdoor pen may be roofed.  During the grazing seasons, goats, sheep and cattle must be allowed to pasture daily. The outdoor pen for pigs must have litter to nose and root. Poultry must be able to spend at least 1/3 of their life outdoors in an outdoor pen with at least 50 % covered in undergrowth.

How well do organic animals fare?

Feeding of animals in organic production has many limitations, but it does not appear to affect to milk yield of cows. Cattle in organic farm does not seem to have less udder or hoof problems compared to traditional production.

Broiler chickens suffer slightly less in organic production, but using slow-growing broiler breeds in organic production has clearly improved animal welfare. In some studies hens show slightly more pecking and cannibalism in organic production, perhaps due to increased light and flock size (egg-laying hens in traditional production are often in cages with 2-7 other birds). In other studies the beaviour of hens was similar in organic and traditional farms.

For pigs the results of actual welfare in organic vs traditional production are mixed. Organic pigs seem to have more joint injuries and liver parasites, but less lung sac inflammations and lung infections. They have less tail damange than traditionally reared pigs, likely due to more stimuli and lower animal density.  All in all, organic farms seem to suffer from the same welfare problems than traditional farms.

Behaviour and welfare of pigs

Pigs differ from other ungulates in many aspects: they give birth to many offspring at once, they are omnivorous, they build a nest, sleep for 12-14 hours straight and they prefer to rest close to other members of the pack. Pigs were originally domesticated from wild boars 9000 years ago in Turkey. Like chickens, pigs have changed in phenotype, but they still share instincts with their wild ancestors. Pigs are omnivorous: they eat vegetables, mushrooms, nuts, fruit, insects, worms, small animals and even carcasses.

Senses and social behaviour

Pigs rely strongly on their sense of smell and hearing. Sows recognize their piglets by smell, and boars smell the sows to check their heat. Voice and hearing are very important in the social behaviour of pigs. Pigs "chat" nearly constantly in quiet grunts to stay in contact with their pack. Warning signals and cries for help are high-pitched and loud. Boars sing a "love song" to attract sows, and the sow's voice signals tell the piglets when milk is available.

(c) Daily Mail. Check their article about pig slaughtering.

Pigs can't see very well. Thus their gestures are not subtle and small, but require a lot of space. For example, a dog recognizes a slight turn of the head as a calming signal. If a pig needs to calm a stronger animal, it turns away completely and then runs away for a short distance. In piggeries this is often impossible, so fights and injuries are common. Naturally pigs live in peaceful groups with stable social structure. In piggeries groups are often mixed, so the structure changes a lot and the animals have to create the "pecking order" over and over again.

Unlike many other animals, pigs are contact animals. A sow does not lick its piglets, nor do pigs lick one another. Instead, they eat in groups and sleep side by side, close together. Even mating behaviour is rather straightforward: instead of courting, the boar can just mount the sow. Sows have a standing reflex, which means that in heat it will stand still when pressure is applied to it's loins. In addition to sleeping, eating is also synchronized. Pigs wake up at sunrise, and spend most of their time nosing the ground for food. They eat for 8 hours, and sleep 12-14 hours a day.

(c) visualphotos.com

Cleanliness: Contrary to popular belief, pigs are very tidy animals. They always separate a sleeping area from eating area and "bathroom" area. In piggeries this is not possible, and pigs are forced to sleep in their feces and eat in a dirty environment.

Skin care: Pigs have two ways for skin care: wallowing in mud and scratching themselves against walls. Wallowing in mud is not just fun, it also cools the animal on a hot day, rubs away dead skin and removes parasites.

Thermoregulation: Piglets under 3 weeks of age cannot thermoregulate, and in piggeries they depend on heat lamps. In the wild piglets live in a nest built by the sow, so they stay warm. Adult pigs have almost no fur and no sweat glands, so they can thermoregulate only by changing their behaviour.

Parturition and weaning

One or two days before giving birth, sows start to look for a place for a nest. They may wander several kilometers searching for a good spot. 6-12 hours before parturition the sow begins the actual nest building. It digs a shallow hole, and then collects branches, hay, turf and other materials, which it uses to build a nest. 1-2 hours before parturition the sow lays down on her nest. When the piglets are born, the sow lays passively. Domesticated pigs give birth to 10-15 piglets, which are born about 15 minutes from one another. After birth piglets instinctively crawl to the udder and start suckling. If a piglet doesn't get colostrum within few hours of birth, it will die. Colostrum is vital, for the piglets have no antibodies. If the sow is vaccinated before parturition, the piglets will get immunity as well.

For the first three days the piglets fight for teats, but they then develop a clear "teat order": each piglet has its own teat. This is important, because after 12 hours the sow gives milk only once every 45 minutes. It announces milk letting by grunting, and every piglet has about 10 minutes to find a teat and suckle.

(c) Keith Weller / Shutterstock

The sow stays in her nest for the first 1-2 days, after which she leaves the nest for a short time as she goes eating. On 4th - 5th day the piglets leave their nest to follow the sow, and learn to find solid food. After 10-14 days the sow and her litter leave the nest and return to the herd. If the piglets do not follow the sow at this time, she may abandon the whole litter. The sow starts weaning her litter from the first week by slowly introducing the piglets to solid food and by regulating her milk letting. Final weaning will happen when the piglets are 10-25 weeks old, depending on the availability of food.

In piggeries sows are not allowed to build nests, and they are often confined to tiny parturition crates for weeks. The crates don't allow the sow to turn around, sometimes not even to stand up. Crates are used so the sow wouldn't lie down on the piglets. Naturally the sow has an anti-crushing behaviour, but in piggeries the sow often cannot hear if a piglet screams when sat on. Studies show that parturition is faster, more piglets are born alive and the sow lets more milk when giving birth freely, compared to birthing crate. Building a having a sest also calms the sow, calms the parturition and improves the relationship beween the sow and the piglets.

Welfare of pigs

The welfare of pigs consists of several basic building blocks:

• health
• air quality and temperature
• Pen structure (size of pen, flooring material)
• availability of litter and  other stimuli
• social environment (stable groups)
• feeding (appropriate feed, enough space for all pigs to eat at the same time, enough roughage)
• Attitude and skills of the caretaker

Pigs would eat for 8 hours every day. In a piggery this isn't possible, so the animals need plenty of modifiable litter and other objects which they can nose, chew, eat or otherwise modify. Straw, tree branches or hemp / sisal ropes are very good for this purpose. Problems with any of the factors of pig welfare may lead to the most serious behavioral prolem in any piggery: tail biting. Tail biting has been discussed in the entry about pig diseases.

In piggeries, pigs are moved from one department or piggery to one another several times. Each department should take into consideration the needs pigs have at that particular age.

Parturition dept: Since piglets are very sensitive, clean, dry and warm environment is vital for them. During the first few days piglets are castrated, ear-marked, given a tattoo and an iron injection, and their canines are filed. All these cause pain and risk for infections. Parturition dept must have clean space available for these operations. Flooring material is important, so the feces and urine can be cleaned, but the floor isn't too hard or cold for the piglets.

Intensive piggery, a "hog lot"(c) Wikipedia

Weaning dept: High-quality and clean water and feed are important to young pigs, who still have no stomach acids to kill any bacteria they ingest. Stable groups and temperature are needed, and stimuli help the pigs to relieve stress and pass the time.

Meat pig farm: For adult pigs, stable groups and enough space are important. They must be able to sleep together and eat together, have separate areas for eating, sleeping and defecating/urinating, and they need space for social behaviour. Stimuli are also important. Temperature can vary more than in previous departments.

Department for pregnant sows: Like the meat pig farm, but pregnant sows need even more space than meat pigs.

Behaviour and welfare of poultry

A red junglefowl male. (c) James Warwick

Modern chicken was domesticated from the red junglefowl, gallus gallus, approximatey 8000 years ago. The junglefowl lived in a flock in the protection of a thick undergrowth. Even though breeding has increased the growth and egg-laying capacity of modern chickens, they still share many behaviours and needs with their ancestor.

Flock and social behaviour

Naturaly, chickens form flocks of 20 chickens and 1-3 roosters. Flock size can vary from 5 to 30 chickens. The rooster tends to his chickens, ensuring their safety and mating with them every night during the egg-laying season. Young birds live on the edges of the flock. Even though chickens rest tightly side by side, during daytime they keep some distance between each others.

Chicken flocks have a rather strict social order, where the oldest and largest birds with the largest comb (the red thing on the top of a chicken's head is called a comb) dominate. Young chicks begin finding their place in the pecking order at the age of 6-8 weeks, and the order is all settled in 1-2 weeks. Chickens can recognize only up to 80 other members of the flock. When the flock size is larger, like in most henhouses, the pecking order is never stable. Fights are common in such circumstances. Roosters have a calming effect on flocks of chickens. Some producers keep roosters in their henhouse just to keep the peace.

Senses and daily schedule

Chickens have an excellent eyesight, and they can see 330º around them. In the dark chickens can barely see, so they climb up to roost or trees to spend the night, safe from predators. However, chickens can see UV-light, and in fact recognize one another by sight. Roosting during the night is a strong need for chickens, and the roost must be about 1,5 metres from the ground. The most dominating birds fly to the top, while other birds settle close together to the lower branches. In a henhouse, where the light program is controlled, "night" has to come slowly after a period of "twilight". This serves as a warning to the chickens, and they can make their way to the roost while they still can see. The roosts actually also help young chickens to develop 3D visualisation, if they are allowed to roost when very young. Chickens allowed roosting later in life never learn to use them, and have poor 3D visualisation.

After a night's rest the chickens wake up at sunrise, and lay eggs. After laying an egg the chickens eat, and would spend 90 % of the day searching for food. In midday the birds rest and bathe in sand, and afternoon is dedicated for tending to their feathers and mating. Right before night time chickens eat as much as possible, storing energy for the night. Chickens' diet consists of seeds, green feed, insects, worms, larvae and even mice. Chickens prefer to search for their food by pecking at litter or ground, instead of eating for a full bowl. 

Dust bathing. (c) The Daily Dish

Bathing is an important need for chickens. Chickens bathe in dust every other day, throwing sand on their back and flapping their wings. Sand helps to keep parasites away from the bird's skin, and keeps the feathers healthy. Chickens bathe also in sunlight, opening their wings and sometimes laying down on their backs. The reason or benefits of sunbathing are still unknown. Like other birds, chickens also arrange their feathers and stroke them with their beaks, spreading the fat from their skin to the feathers. This nsures the feathers' insulating capacity.

Reproduction

Egg-laying hens in henhouses are bought from breeding farms, where fast-growing but infertile hybrids are created for production use. These animals simply lay eggs until they are culled and the meat is either destroyed or used as animal feed. Naturally, a chicken would lay eggs once a year, during springtime. The chicken leaves the herd to build a nest. She walks to her nest each morning, lays one fertilized egg, and returns to mate with the rooster in the afternoon. Egg-laying stops when she sees about 10 eggs in her nest. She will then incubate the eggs, occasionally turning them around, for 21 days.

(c) Quaker Anne

The chicks recognize their mother from her sound right after hatching. Their yolk sac has enough nutrition for two days, after which they need to start picking food on their own. The mother teaches the chicks where to find food. Chicks develop fast: they run at the age of 2 days and fly short distances at the age of 10 days. For the first three weeks the chicks cannot thermoregulate well, and must sleep under their mother's wings. At 1,5 months of age they already sleep on roosts. Until three months of age the chicks stay with their mother. After that the chicken drives male chicks off to another flock or to the borders of the current flock.
 

Production environment creates behavioural problems

Chickens in modern henhouses live either in small cages or in flocks of tens of thousands of birds. They rarely have any litter to peck, and their food is served from a bowl. Roosts are rare, and often too low. Bathing behaviour is often impossible due to lack of space and bathing material. If chickens are not allowed to roost or to search for their food, they will get frustrated and stressed. This leads to disruptive behaviour, which can be very serious. Frustrated chickens often peck one another, tearing away feathers and causing wounds. Chickens are omnivorous, so seeing blood excites them to peck on the target even more, possibly killing the victim even if it is a chicken of the same flock. Cannibalism among production chickens is not rare, but it is abnormal.

In production henhouses, the eggs are collected daily. The visual stimuli of "enough eggs in the nest" never occurs, and the chickens continue to lay eggs indefinitely. Their metabolism is thus under heavy stress: it is meant to create 15 eggs a year instead of 300. To meet the production requirements, the chickens are fed heavily, so they may grow too fast. Fast growth combined with small cramped spaces (cages) causes leg injuries and weak muscle strength.

When chickens are reared on floor  instead of cages they have better chance of exercise, bathing and searching for food. Flock sizes are often huge, so fights, cannibalism, feather pecking and injuries are more common than in cages. Free movement may also increase the risk of sickness. Individua chickens are more difficut to check when they're on the floor

How to reduce disruptive behaviour?

• Using red light prevents the chickens from seeing blood, thus decreasing their instinct to peck an already injured bird.
• Dimming the lights
• Observing the birds more closely, and removing those who peck others
• Most importantly: allowing the animals access to roosts, bathing material and to search for food

Broiler production

Packed chickens. (c) Antaryamin's blog

 Broilers are hybrid birds reared on floor in flocks of tens of thousands. They are bred to grow incredibly fast and to become large, so each animal would produce the maximum amount of meat. A broiler lives only five weeks. It is sold from the commercial breeded as an egg or small chick to the broiler farm. Because their fast growth and cramped space, leg injuries, heart and circulatory problems are very common. Many broilers die suddenly of heart failure, and are simply removed from the poultry house. When the birds are five weeks old, they are gathered to crates using a "hoover", a chicken catcher. Gathering and transporting the animals often leads to immensely painful broken legs and wings in addition to stress and fear.


Chickens breeding broiler-breed chicks are also bred to grow as fast as the broilers. However, such a fast growth would kill the animal before it's able to reproduce, so the broiler dams are fed only 30 % of what they would need. At the age of 39 days, a freely fed broiler chicked weighs 2,2 kilos, but a broiler dam on limited feeding weighs only 615 grams. The dams are constantly hungry and frustrated, so they fight often during feeding time, and drink water excessively to ease their hunger. Elevated stress levels have been measured. Stereotypical behaviour and pecking are common due to high stress.


45 days: The life and death of a Broiler Chicken is a short 12-minute video of how broilers are reared. Warning: may disturb sensitive viewers: