What are the comprehensive prevention and control measures for pig pica?

Pica in pigs is one of the problems commonly encountered in @#@227@#@ production, and the disease occurs frequently, especially in winter and spring when light duration is insufficient and temperatures are low. Improper feeding management, an unsuitable environment, unbalanced feed nutrient supply, disease, and metabolic disorders are the triggers of this disease. Because of long-term pica, pigs often suffer stunted growth, emaciation, and loss of appetite, causing unnecessary economic losses for pig farmers.

1. Clinical symptoms

Pigs suffering from pica show tail biting, ear biting, rib biting, and navel sucking, and are especially fond of eating chicken manure, drinking urine, rooting in the ground, and gnawing on wooden sticks, with phenomena such as restlessness in the pen and jumping over rails. Mutual biting and fighting is one of the more vicious forms of pica, shown by pigs being sensitive to external stimuli, behaving restlessly, having a reduced appetite, and having a fierce look. At first only a few pigs bite and fight each other, then gradually multiple pigs join in, mainly biting tails and in a few cases also biting ears; the tail area of the bitten pig loses hair and bleeds, and the herd then develops a depraved appetite for blood, with the harm gradually expanding. Bitten pigs often show loss of skin and hair on the tail, which affects weight gain, and in severe cases can lead to secondary infection with osteomyelitis and abscesses; if not treated in time, it can be complicated by septicemia and other conditions, resulting in death.

2. Causes of the disease

1. Improper management: excessive stocking density, cramped rearing space, insufficient drinking water, large differences in size and strength among pigs in the same pen, and competition for rank are triggers for pica.

2. Environmental factors: the relatively high incidence in winter and autumn may be because a dry and highly dusty environment causes pigs to become irritable and show aggressive behavior. For example, if the temperature inside the barn is too high or too low, ventilation is poor and harmful gases accumulate, the lighting in the pig house is too strong so that pigs are in an excited state and restless, or pigs are frightened, the weather changes abnormally, or the pig pen is damp, all of these can cause pigs to feel discomfort and ultimately trigger biting and other pica behaviors.

3. Individual differences: if pigs of different breeds or pigs of the same breed with too large a difference in body weight are raised in the same pen, conflicts and fights for dominance occur because of differences in breed and living characteristics. When differences between individuals are large, the phenomenon of the big bullying the small often appears in occupying sleeping area and competing for feed.

4. Disease factors: when pigs have external parasites such as lice and mange mites, it can cause skin irritation and restlessness in the pigs, and rubbing in the pig house leads to exudate appearing behind the ears, on the ribs, and other places, which attracts other pigs and induces tail biting. Internal parasite diseases in pigs, especially pig roundworm, stimulate affected pigs to attack other pigs. Hormonal stimulation in the pig's body causing emotional instability can also lead to tail biting.

5. Nutritional level: when the nutritional level of the feed is lower than the feeding standard and cannot meet the nutritional needs of pig growth and development, tail biting can occur. In addition, an imbalance of various trace nutrients in the diet, such as deficiency or imbalance of potassium, sodium, magnesium, iron, phosphorus, calcium, and vitamins in the diet, can also cause this condition.

6. Natural instinct: pigs love to play and move about; when the environment is comfortable, young pigs bite the tails of other pigs and imitate each other, and the imitative nature of pigs is one of the reasons why pica occurs in pigs and triggers pica in large groups. At the same time, skin breakage and bleeding and other external injuries also trigger pigs to bite and fight each other.

3. Prevention and control measures

1. Strengthen management

① Reasonably arrange the pig house: individual differences among pigs in the same pen should not be too large and should be as close as possible; stocking density should not be too high. The stocking density of pigs is generally determined according to the size of the pig house, and the principle is that it should be neither crowded nor affect growth and allow normal feeding and drinking, denser in winter and sparser in summer. Ensure a rearing area of 0.8-1 sq m per finishing pig, 0.6-0.7 sq m per growing pig, and 0.3-0.5 sq m per piglet.

② Raise pigs with vicious habits separately: the occurrence of tail biting is often caused by individual aggressive pigs. If a pig with a tail-biting vice is found in the pen, it should be picked out promptly and raised separately. Tar can be applied to the pig's tail, or liquor above 50 degrees can be sprayed on the whole body and the tip of the nose of the pig, 3-5 times a day, and generally the tail biting can be controlled in 2 days. At the same time, isolate the bitten pig, and the bitten pig's wound should be promptly cleaned with potassium permanganate solution and coated with iodine tincture to prevent wound infection; in severe cases, antibiotics can be used for treatment.

③ Avoid stress: properly regulate the temperature inside the pig house, strengthen ventilation of the pig house, and avoid stress caused by factors such as draft invasion, manure contamination, and foul air. Feed high-quality feed at fixed times and in fixed amounts, drinking water should be clean, troughs and water troughs should be sufficient, pay attention to hygiene, and avoid competition for feed and drinking water.

④ Dock piglets' tails in time: docking the tails of piglets is an effective measure to control tail biting. The best time for tail docking is around 3 days of age, and the best tool for tail docking is a 1000-watt electric soldering iron; after plugging in and heating until red, it is best if it can burn the tail off within 2-3 seconds. Many farmers use other methods for tail docking, resulting in infection.

⑤ Distract the pigs: place toys such as chains, balls, old tires, and green feed in the pig pen to distract the pigs, thereby reducing the occurrence of tail biting.

⑥ Use compound feed with balanced nutrition: choose high-quality feed ingredients; if the diet is mainly corn and soybean meal, attention must be paid to adding methionine to balance the amino acids. Appropriately increase the amount of edible salt, and it is best to use mineral trace element salt powder. Flavoring and digestive aids can also be added to the feed, adding garlic, white sugar, and market @#@136@#@ flavoring agents to improve pig pica.

2. Comprehensive treatment

Increase lighting by 2-3 hours per day. Generally, each ton of feed can be supplemented with 2 kg of electrolytic multivitamins, 200 g of Ankangning, 200 g of Xue'er, 200 g of chromium complex, 44.2 kg of Liyifeisu, 500 g of Weitakang, 2 kg of Youpei, 3-5 kg of baking soda, and 300 g of Aiweijia, fed continuously for 5-7 days. Based on the author's practical experience, adding an appropriate amount of Yishiling and Golden Partner to the feed and feeding continuously for 10-15 days can achieve good results.

3. Symptomatic treatment

For pigs with the habit of gnawing walls and gnawing pens, red soil or shale powder used for firing bricks can be fed to supplement various trace elements such as iron, manganese, zinc, and magnesium.

For those with the habit of eating pig manure and chicken manure, vitamin B12 can be injected intramuscularly, 500-1500 ml each time, once a day, for 3-4 consecutive days.

For those with the habit of eating lime, calcium and phosphorus should be added to the feed, such as slaked lime and bone meal; vitamin AD3 and vitamin E powder can also be added to the feed, or vitamin D3 colloidal calcium can be injected intramuscularly at 5-10 ml, for 4-7 consecutive days.

Pigs suffering from parasitic diseases should be dewormed in time. Commonly used deworming drugs include albendazole, trichlorfon, ivermectin, and avermectin.

For pigs that gnaw and eat bedding straw, multivitamins can be given orally or compound vitamins can be injected intramuscularly, 10-20 ml each time, once a day, for 3-4 consecutive days.

For sows with the habit of eating afterbirth and fetuses, in addition to strengthening care, 100-300 g of river shrimp or small fish can be boiled into soup and given as a drink, or fish meal can be added to the feed at 50-100 g per pig per day, fed continuously for 10-20 days.

For pigs that love to gnaw bricks, eat coal cinder, and drink urine, 0.5%-0.8% salt should be added to the feed; the added amount must not exceed 1% to prevent salt poisoning.