Fundamentals of production technology in rabbit and fur farming

Production of rabbit and fur-bearing animal products is promising due to the high demand for dietary meat, as well as down and valuable fur raw materials.

Rabbit meat does not cause allergies in humans and is recommended for the diet of children and elderly people with stomach, liver, and cardiovascular diseases. The human need for rabbit and fur-bearing animal products obliges students to study the biology and production technology of this sector.

Lesson objective: to study biological features, rabbit husbandry hygiene, feeding of minks, nutrias, and production processes in technology.

Task 1. Study the husbandry and biological features of rabbits:

• The stomach is single-chambered and voluminous (200 ml); gastric juice is secreted continuously.
• Adults eat feed 25–30 times a day, young animals 50–60 times, for 2 minutes per feeding.
• They provide diverse products: meat, pelts, down, and fertilizer.
• Rabbits reach slaughter weight in 9–10 weeks.
• Fecundity is on average 8–9 kits, sometimes 18–19 per litter.
• Growth intensity is at its maximum during the embryonic period.
• Kits are born hairless, blind, and helpless; after 2 days they increase their body weight by 30%, and by the 6th day, they double their weight. From day 20–30, daily gains are 40 g/day, and from 3 months of age, 16–20 g. At 3.5–5 months of age, they weigh 2.5–3.5 kg.
• Rabbit milk is 4 times more nutritious than cow's milk: 10–20% fat, 13–15% protein, 1.8–2.1% lactose.
• Males are introduced to mating at the age of 6 months. The ratio is 8 females per 1 male.

Task 2. Familiarize yourself with the husbandry and biological features of nutrias and minks:

• The stomach is single-chambered, and the intestine is 8–10 times longer than the body. They are not adapted to digesting fiber and are similar to pigs in terms of feeding.
• Growth ends at 1.5 years.
• Sexual maturity is at 3–4 months; they are mated at 7–9 months.
• Fecundity is 5–7 pups (up to 18). They combine pregnancy with lactation.
• Pregnancy duration is 130 days (127–137).
• Newborns weigh 150–200 g; they are born mature, with eyes open, covered in fur, and capable of consuming mother's milk and regular feed from the first days.
• Parturition occurs at night or early in the morning. After parturition, the female produces black feces due to consuming the placenta.
• Nutrias are slaughtered at the age of 6–7 months when they reach a live weight of 4.2–4.5 kg.

Task 3. Describe the housing methods for rabbits:

nutrias:

minks:

Task 5. Study the specifics of rabbit reproduction and raising kits.

• Mating is manual, involving the correct selection of females for males. Before mating, it is necessary to feed them so that the body condition of the rabbits is average.
• Age of first mating: females at 4–5 months, or 5–6 months (for large breeds), males – 6 months.
• For mating, the female is placed in the male's cage, mating is observed, and re-mating occurs after 5–15 minutes. After mating, the female is returned to her own cage. The female is checked for heat after 5 days; she is placed back into the male's cage, and if she moves away from the male, she is considered pregnant.
• On day 12–15, pregnancy is checked by the palpation of the abdomen, and the mating date is recorded.
• Mating on the farm should be intensive (5–6 days) so that litters are synchronous.

To obtain high-quality pelts, an animal slaughter plan is drawn up.

Table 1 – Birth and slaughter dates for young stock for meat and pelts

• To obtain a large number of offspring, intensive breeding is used, i.e., partially combining rabbit lactation with pregnancy.
• To plan production processes in rabbit technology, a plan of matings and litters is drawn up.

Table 2 – Sample calendar of matings and litters

• Before kindling, does must be provided with nest boxes and a large amount of clean bedding. 5 days before kindling, the nests must be disinfected.
• Kindling occurs at night (mainly) and takes 16–20 minutes. Kits are born small, hairless, and blind.
• If a doe has many kits, some of them can be moved to another female on the 2nd–3rd day, preferably one with higher milk production.
• The transferred kits must be cleaned of the original mother's nest down, rubbed with the new female's down, placed inside, and covered with nesting down.

• On the 5th day, the kits develop down.
• On the 10th day, their eyes open; on the 16th–18th, they leave the nest and try feed.
• After the kits leave the nest, nesting down should be collected, and the cages should be cleaned and disinfected.
• The traditional period for weaning kits from their mothers is 30–45 days.
• With intensive breeding, the doe is mated on the 1st–2nd day after kindling, and kits are weaned a few days before the mother's next kindling.
• With semi-intensive breeding, the doe is mated on the 15th day after kindling, and kits are weaned at the age of 40–45 days.
• Weaned kits are sorted by sex and kept in groups of 5–6 animals until 3 months of age; from 3 to 5 months, up to 4 females or one male are kept in each cage.

Task 6. Study the methods for collecting and storage of rabbit wool.

Wool collection, slaughter of rabbits, and primary processing of products

Adult rabbits of wool breeds are plucked every 1.5 months, based on a hair length of 5–6 cm. The main method for collecting the raw material is careful plucking, which starts from the back of the animal. For young stock, wool is collected in stages at strictly defined times. The first collection is performed at the age of 2–2.5 months so that the soft hair does not have time to mat. The second collection is scheduled for 4–4.5 months, and the third for 6–6.5 months.

Collected wool is stored in tightly closing boxes measuring 80 × 50 cm, which hold 5–6 kg of raw material. To prevent the wool from matting, pegs are installed vertically at the bottom of the boxes at a distance of 10–12 cm from each other. Bags of naphthalene hung inside the boxes help protect the product from moths.

Several practical methods are used for rabbit slaughter: a blow with the edge of the palm or a round stick to the back of the head, a blow to the forehead, nasal bone, or crown, or electrical stunning. Immediately after this, the carcass must be hung on hooks and dressed properly. Below is a step-by-step instruction for bleeding, skinning, and evisceration.

1. Hang the stunned animal by one or both hind legs on V-shaped hooks.
2. Immobilize and bleed the carcass: with your right hand, pull the free hind leg behind the back with a twist, holding the carcass with your left hand. If blood flow is poor, use a knife to cut the nasal septum or remove one eye.
3. Detach the ears, then cut off the front paws at the carpal joint, having first made a circular incision around the carpal joint and breaking it.
4. Inspect the fur and remove any bloodstains or dirt with a swab soaked in water.
5. Make a circular incision around the hock joints of the hind legs, then make incisions along the inside of the lower leg and thigh through the center of the anus.
6. Remove the skin in a tube shape (removing it as a flat pelt with an incision in the middle of the abdomen is also acceptable), pulling it from the tail to the head without using a knife, freeing the front paws. Carefully trim the tissues around the eyes, nose, and lips for removal from the head.
7. Perform evisceration: make an incision along the white line of the abdomen from the anus to the chest, and remove the gallbladder and bladder. Cut the pubic symphysis, extract the gastrointestinal tract, as well as the liver, heart, lungs, trachea, and esophagus. Always leave the kidneys attached to the carcass.
8. Cut off the head between the occipital bone and the first cervical vertebra.

After evisceration is complete, a thorough inspection of the head muscles, carcass, and internal organs of the animal is carried out. Special attention is paid to the absence of pathological changes, the degree of bleeding, and the quality of cleaning. When dressing the carcass, bruises, blood, and hair residues are removed, and the neck incision is cleaned. Then the carcass is washed with warm water from a shower and shaped by tucking the ends of the front paws into incisions on the chest between the third and fourth ribs.

By-products — head, lungs, liver, heart, kidneys, and spleen — are thoroughly cleaned of impurities. Edible raw fat is removed from the stomach and intestines directly during the carcass evisceration process. In a chilled state, such fat is stored for no more than 2–3 days. For longer storage, it must be frozen or salted.

Primary processing of the obtained skins includes carcass preparation, skinning, trimming, degreasing, and preservation. The main and most reliable preservation method is the fresh-dry method. The acid-salt method is used in practice significantly less often. Meat yield directly depends on the rabbit breed.

Sanitary requirements, quarantine, and transport rules

Infectious diseases in rabbit farming pose a serious threat, as they quickly affect the entire herd on a farm. The main barrier against infections is a strict quarantine for all new animals and those intended for sale. To this end, isolated cages located in a separate zone are equipped on the farm. The quarantine group should be serviced by dedicated personnel who do not have access to other facilities of the farm.

The quarantine zone is fully equipped with individual tools: robes, special footwear, buckets, brooms, and scrapers. A disinfection mat is mandatory at the entrance to the isolation ward, which is regularly soaked in a creolin solution. On amateur and small-scale farms, it is also necessary to have spare isolated cages. They are required for the temporary housing of purchased livestock animals or for isolating rabbits suspected of having a disease.

Special cages, suitable for most types of transport, are used to transport rabbits. The maximum time spent by animals in transit is limited. Breeding young stock may only be purchased from farms that are officially free from infectious diseases.

• Animal quarantine period — 30 days
• Transport cage size — 50 × 26 × 40 cm
• Time limit in transit — no more than 3 days
• Water temperature for washing carcasses — 25–30 °С

Herd health control and culling

Regular inspection of the herd is the basis for infection prevention on a rabbit farm. It must be carried out regularly to detect the first signs of infection. A healthy livestock animal is active, eats well, and has a shiny, smooth coat. Sick rabbits are lethargic, refuse feed, look emaciated, and their hair coat becomes ruffled and dull.

During the inspection, the rabbit breeder checks the physical condition of the animals. Special attention is paid to the eyes, nose, paws, reproductive organs, ears (for the presence of mites causing ear mange), and for females — the teats and mammary glands. Disorders in the respiratory system are indicated by a runny nose and wheezing, while gastrointestinal disorders manifest as diarrhea, constipation, or bloating. Upon detecting any signs of illness, the animals are immediately isolated or culled.

Rigorous culling not only stops the spread of infection but also acts as a selection tool. By removing weakened individuals from reproduction, the rabbit breeder forms a breeding herd resistant to diseases. This allows for reduced mortality and increased overall productivity of the farm in the future.

Methods and modes of disinfection

Disinfection allows for the destruction of pathogenic microbes in the animals' environment. Simultaneously, pest control is carried out against disease vectors — disinsection against arthropods and deratization against rodents. Premises, cages, equipment, special clothing, transport, and manure are subject to decontamination.

Any treatment is strictly divided into two consecutive stages. First, thorough mechanical cleaning is performed. It reduces the microbial load and opens access for disinfectants to the surfaces being treated.

1. Remove debris, manure, feed residues, and bedding from cages and premises.
2. Wash and scrape wooden elements with hot water with added soap or soda.
3. Perform physical or chemical disinfection.

For decontamination, mechanical, physical, and chemical methods are used, combining them for maximum effect. For example, manure is first placed in piles for self-heating (biothermal process) and then drenched with a disinfecting solution. Metal equipment and cages are often treated with a blowtorch flame, and equipment is placed under direct sunlight on sunny days.

When using the thermal method, it is important to strictly observe temperature and time regimes. Boiling is the most accessible and reliable method of decontamination. It guarantees the destruction of all infection pathogens.

Chemical disinfection is carried out using solutions, aerosols, or gases. Preparations are applied by spraying, wiping, or immersing equipment in working solutions. Preventive treatment of the entire farm is done twice a year — before the winter-spring mating season and in autumn.

• Inspection by rabbit breeders — at least 2 times per month
• Soda solution for washing wood — 2%
• Preventive disinfection — 2 times per year

Current disinfection with whitewashing of premises is carried out before every kindling and movement of rabbits (weaning young stock, transferring replacement animals, etc.). Creches, feeders, and waterers are treated at least once every ten days. In the event of an infectious disease, a quarantine is imposed on the farm, and forced disinfection is carried out regularly, approximately every 3–5 days.

Final disinfection should be performed after the quarantine is lifted.

In rabbit breeding facilities, the regimen of disinfection treatments should be strictly followed. For example, it should be remembered that before bringing livestock animals to a new farm, the entire territory, as well as production and utility rooms, must be thoroughly cleaned and disinfected.

It is prohibited to use cages vacated by dead or culled animals without prior treatment. It is strictly forbidden to use transport that has been used to haul manure for carrying feed. A sanitary day should be scheduled once a month for a general cleaning of the farm. This can be combined with routine disinfection.

Deratization is the control of rodents, which are carriers of infectious diseases. In rabbit breeding, this control is primarily aimed at exterminating rats and mice. Rats often maim young rabbits by biting off paws that have fallen through the wire mesh. Sometimes they gnaw through wooden walls to enter the cage. Furthermore, the presence of rats causes severe anxiety and aggression in nursing does. This leads to a loss of appetite, a decrease in milk yield, and injury to young rabbits, which, becoming frightened, begin to lag in growth and often suffer from gastrointestinal disorders, and sometimes diseases of the central nervous system.

There are several methods of rodent control:

• mechanical;
• chemical;
• biological.

The chemical method of exterminating rodents is the most common and effective. Rats and mice in the rabbitry consume leftovers of feed mixtures, grain, etc. The chemical control method is based on this. Poisoned bait is placed in the rodents' burrows.

Bait must be prepared with extreme caution, ensuring that poison powder is not dispersed and inhaled with the air. After working with poison, hands must be washed thoroughly with warm water and soap, and equipment must be cleaned with a 2% soda solution. Deratization using poisons should be supervised either by the farm's veterinary staff or by specialists from the sanitary-epidemiological station.

Biological methods of rodent control include the use of their natural enemies and pathogens of infectious diseases. In a domestic setting, this control is reduced to the use of cats, and sometimes hedgehogs. Bacterial baits are also prepared, causing the death of rodents from infectious diseases. Combined preparations are also used, for example, bactocoumarin. It is a combination of bacterial agents and zoocoumarin.

Mechanical means of deratization can be:

• multi-use (live traps, funnel traps, etc.);
• single-use (spring traps, etc.).

It is advisable to place all of them near burrows or in areas where rodents appear most frequently. Bait should also be placed here: bread, cheese, vegetables, fat, etc.

Disinsection includes measures to eliminate harmful insects (and their larvae) that carry pathogens of infectious diseases, parasitize on animals themselves, and contaminate feed. Mechanical, physical, chemical, and biological agents are also used for disinsection. Among the mechanical methods of controlling insects in premises, the most common is trapping them on sticky paper.

Physical agents are widely used for disinsection. The application of high temperatures (fire, dry heat, boiling water) is very effective. Using a blowtorch flame is effective for treating cracks in premises and cages to destroy mites. After scorching, the cracks should be sealed (with clay, paint, whitewash, etc.).

Among the biological means of insect control, birds should be mentioned first.

There are a number of effective chemical agents (insecticides) available for controlling insects and mites. Among them are some well-known disinfecting preparations, such as creolin.

Insecticides are divided into four groups: contact agents – insects die upon contact with them; intestinal agents – kill insects when ingested with food and water; fumigants, which act on the respiratory organs; and repellents, which are deterrent preparations.

To control flies and other insects, premises are most often sprayed with 0.5–2% aqueous solutions of chlorophos, as well as 2% emulsions of trichlormetaphos and SK-9. All these treatments are conducted according to the prescription and under the direct supervision of veterinarians.