Analysis of Why Pregnant Sows in Better Body Condition Are More Prone to Sudden Death
Why are pregnant sows in better body condition more prone to sudden death? What causes it?
The death of pregnant sows is undoubtedly a major hidden danger for pig farms. For this disease, prevention is most important. Both nutrient intake and health status during pregnancy in sows have an impact. If you want to control the prevalence of this disease on a pig farm, you must understand exactly what causes sudden death in pregnant sows.
1. Death from intestinal bleeding and collapse
After sows become pregnant, they are fed large amounts of feed containing crude fiber, have insufficient drinking water, and receive little supplemental green fodder. They live long-term in a very small activity space, or even have no activity space at all. Over time, the sow's body weight increases greatly, body condition is good, and severe constipation is present. Combined with many other factors such as insufficient gastrointestinal motility, this causes the sow's cardiopulmonary load to become too heavy. The pressure causes the inferior mesenteric artery to rupture, leading to accumulated blood and massive hemorrhage, and finally the sow collapses and dies within a short time.
Sudden death manifestations: It mainly occurs in late gestation and before farrowing. The sow suddenly falls to the ground and dies, accompanied by gastrointestinal bleeding and pale skin. Before death, breathing is rapid, muscles tremble, and the sow is unable to stand. The feces excreted by the sow are dry and hard, and are accompanied by undigested feed. The mental state is poor. After falling down, death occurs in 3-5 minutes, with no timefor treatmentor rescue.
2. Death from gastrointestinal bloating
It occurs more often in early gestation, generally in sows pregnant for 1-2 months, and is mainly caused by Clostridium welchii. When the external environment changes abruptly, the resistance of the pregnant sow is at a low level and the intestinal flora becomes imbalanced, causing rapid reproduction of the Clostridium welchii pathogen and production of toxins, resulting in necrotizing enteritis caused by diffuse intestinal hemorrhage.
It generally occurs as sporadic outbreaks, with acute onset, short course, and high mortality. The mortality rate is 100%. After onset, the diseased pig's abdomen becomes distended, and tapping it with a finger produces a drum-like sound. It occurs mostly in the cold, damp winter and spring seasons.
Sudden death manifestations: Sudden collapse without symptoms, death from convulsions, difficulty breathing, breathing with the mouth wide open, typical abdominal breathing, and it generally affects multiparous sows in better body condition on the pig farm. During collapse, muscle trembling, ataxia, paddling of the limbs, and whitening of the skin appear; there is notreatmentor rescue time;
Generally, the body temperature of the diseased pig is normal, and abdominal distension appears after death; in a few cases, body temperature rises, and after death body temperature drops; there are also a few diseased pigs in which white foam flows from the mouth and nose.
3. Pathogenic bacteria and parasite infections
The death of pregnant sows is also related to some diseases. Sows themselves carry immunosuppressive pathogens such as porcine reproductive and respiratory syndrome and porcine circovirus, and in addition there are immunosuppressive factors such as mycotoxins in the feed. When they are moved to a different pen in late gestation and encounter some stress factors or invasion by other pathogens, the balance between their own immunity and disease-causing factors is disrupted, thereby inducing disease in the sow and even causing death.
This includes internal medicine, obstetrics, or nutritional causes, and also includes infectious diseases and viral diseases; Toxoplasma infection is the main parasitic cause of death in pregnant sows.
Sudden death manifestations: Pathogenic bacterial infection induces disease-related death. The diseased pig shows symptoms such as elevated body temperature, poor appetite, poor spirits, heart failure, indigestion, inability to stand, rapid heartbeat, difficulty breathing, panting, and gradual emaciation;
Disease symptoms appearing here include such conditions as classical swine fever, circovirus, porcine reproductive and respiratory syndrome, pseudorabies, and so on; some do not eat before death, die lying on their side, have bloody fluid flowing from the mouth, and show no other obvious lesions on the body surface.
4. Excessive nutrient intake
If too much feed is fed during gestation, it will increase the metabolic burden on the sow and cause death due to excessive obesity. If the crude fiber content in the feed is too high and the intake is too much, it will lead to excessive body condition. Too much fat is deposited around the uterus, under the skin, and in the abdominal cavity, which can cause circulatory disturbance in the uterine wall, disrupt the metabolic and body balance mechanisms of the mother and fetuses, and lower resistance;
In addition, if the sow feed is not changed in time during gestation, it leads to overnutrition in the sow. Sudden death manifestations: In mid-to-late pregnancy, body temperature is below 38°C. The diseased pig shows constipation, agitation and restlessness, reduced or completely lost appetite, lies on the ground unable to rise, walks incoordinately, and is depressed. Some pigs show neurological symptoms, muscle tremors, and head shaking; finally they become comatose, gradually weaken, and die.
Comprehensive prevention to avoid death in pregnant sows
In feeding management, attention should be paid to the amount and the combination. Concentrate and roughage can be combined in appropriate amounts for feeding, and a certain amount of green fodder should be supplemented so that the pig's gastrointestinal tract can be assisted and motility increased. Feed should be kept dry and fresh. When feeding, the method of feeding small amounts and adding frequently should be adopted, and sows should be allowed to drink clean water at all times.
After gastrointestinal bloating occurs, there is no corresponding drug fortreatment, but tiamulin can be added to the feed for prevention. Metronidazole and lincomycin also have a strong inhibitory effect on Clostridium welchii.
In addition, year-round vaccination should be carried out for some viral diseases, and bacterial diseases should also be prevented. Normally, vitamins can be used for health care, more green fodder should be provided for feeding, deworming should be done 4 times a year, feed management for pigs should be strengthened, stress should be reduced, and the resistance of pregnant sows should be improved.
Reasonable feeding planning should be carried out for pregnant sows, more green fodder should be fed, and the body condition of sows should be monitored every day to adjust feeding. For sows that are too fat, energy substances in the feed should be controlled, using a progressive daily reduction method so that the sow can exert its own self-regulating function, which can reduce and avoid death caused by continued obesity.
In addition, a poor environment can also cause bacterial infection, so pregnant sow housing should be kept dry and hygienic. When disinfecting with pigs present, sows should be prevented from being harmed, and a suitable disinfectant should be selected. During gestation, sows should be given an appropriate amount of exercise space and allowed free movement to ensure the body remains in a healthy state. Measures for the pig house should be taken according to the season: heat prevention and cooling in summer; warmth preservation in the pig house in winter, which can reduce the number of movements.