During the transition from autumn to winter or in early spring, the weather’s most notable feature is roller-coaster-like temperature changes. At noon, when the sun shines, the temperature in the pig house can reach the twenties, making it feel like summer; by evening, once the sun sets, the temperature drops sharply to single digits. The temperature difference within a single day can reach more than ten degrees. People may sneeze and have runny noses if they are not careful, let alone densely housed pigs.
Many farmers think pigs have thick skin and can handle a little cold. In fact, pigs have almost no sweat glands, and their ability to regulate body temperature is far inferior to that of humans. When the morning-to-evening temperature difference exceeds 8-10°C, pigs must expend a great deal of energy to maintain their body temperature, causing their immunity to decline sharply.
At this point, various pathogens lurking in the pig house can take advantage of the situation. Pig colds (upper respiratory tract infections or swine flu) are often the “first shot” in disease outbreaks on pig farms during this season. A cold itself has a low fatality rate, but it is like opening the “city gate” in the pigs’ respiratory defenses. If it is followed by infections such as contagious pleuropneumonia, Glässer’s disease, or PRRS, the situation can develop into widespread deaths.
Have you spotted the early signs of a cold in pigs?
Colds caused by large temperature fluctuations usually come on suddenly and spread quickly. Within a day or two, pigs throughout an entire pen may show symptoms:
Behavior and feed intake: The pigs suddenly eat less and become lethargic. They like to huddle together for warmth and are reluctant to move around.
Breathing and appearance: Body temperature rises (up to 40-41.5℃), ears feel cool, the conjunctivae are red, and the eyes water. The most typical signs are bouts of coughing and sneezing, with clear or thick nasal discharge.
Stool: Usually, there is no severe diarrhea, but the stool may be dry and hard, and the urine may be scant and yellow, indicating internal heat.
Beware of colds: pig farms must take these “four measures”
To cope with temperature-difference stress, prevention is always more important than treatment. The core strategy is to balance temperatures, block drafts, and boost resistance.
Measure one: Seal off drafts; keep the abdomen warm first.
When daytime temperatures are high, the doors and windows of the pig barn are opened wide. In the evening, temperatures drop sharply. If the windows are not closed in time, cold air blows directly onto the pigs.
Instructions: Before dark in the evening, close the windows and curtains on the windward side. Leave a small gap on the leeward side for ventilation. Be sure to check gaps in the walls, drainage channel openings, and fan louvers. Never let drafts blow directly onto the pigs.
Key point: For piglets and nursery pigs, ensure the heat lamps are working properly and the floor is covered with dry bedding. If a pig’s abdomen gets chilled, it is not only more likely to catch a cold but may also develop diarrhea.
Second strategy: Ventilate scientifically to break the deadlock between “heat retention and ammonia”
To keep out the cold, many pig farms seal their pig houses tightly, causing ammonia levels to soar. Ammonia directly damages the mucous membranes of pigs’ respiratory tracts, allowing cold viruses to invade unchecked.
Procedure: Each day, choose the warmest part of the day, from 11 p.m. to 2 p.m., and open the windows on the leeward side for ventilation for 10-15 minutes. While ventilating, make sure people inside the pig house do not feel a noticeable cold draft. It is better for the temperature to be 1-2 degrees lower than to let ammonia build up because the pig house is “stuffy.”
Third tip: Give pigs warm water, and add an “anti-stress” product to the drinking water.
Water temperatures are extremely low in the morning and evening. If pigs drink cold water, they not only use up a lot of energy to warm it, but it can also irritate their digestive tract.
Action: Provide pigs with warm water whenever possible. Add electrolytes and multivitamins, vitamin C, or astragalus polysaccharides to the drinking water for 3-5 days. This can effectively alleviate cold stress in the herd and improve immunity.
Feeding: Moderately increase the energy concentration of the feed (for example, by increasing the proportion of corn) so the pigs have enough energy to withstand the cold.
Fourth measure: Use preventive medication moderately to establish a defense in advance
Intervene promptly 1-2 days before a sharp drop in temperature, or when you notice the pigs starting to sneeze occasionally.
Traditional Chinese medicine preparations such as Jingfang Baidu Powder and Maxing Shigan Powder can be added to the feed, or amoxicillin + multivitamins can be used to prevent secondary respiratory bacterial infections in advance.
Already caught a cold—how should it be treated?
If obvious cold symptoms have already appeared on the pig farm, remember not to administer fever-reducing injections indiscriminately (especially potent antipyretics such as metamizole or aminopyrine), as this can seriously damage the pigs’ immune systems.
1. Group medication: Administer medication to the entire group through feed or drinking water. It is recommended to use Bupleurum Injection (for fever reduction and antiviral effects) together with amoxicillin or florfenicol (to control secondary bacterial infections) for 3-5 days. Combining this with heat-clearing and detoxifying Chinese herbal medicines (such as Banlangen and Shuanghuanglian) may improve results.
2. Individual treatment: For pigs with severe fever that are not eating, give an intramuscular injection of Bupleurum + ceftiofur sodium, or Shuanghuanglian + lincomycin.
3. Rehydration to sustain life: Pigs with colds and fever are often dehydrated. If a pig has not eaten for several days, glucose normal saline can be administered intraperitoneally or intravenously to maintain its strength.
In closing:
There’s an old saying in pig farming: “A whole gust of wind is nothing to fear; a narrow draft is what you need to watch out for.” A temperature difference of more than ten degrees is a test nature sets for pig farms. One extra round of checks, closing the windows half an hour earlier, or giving the pigs a drink of warm water—these seemingly insignificant things can keep colds out of the pigsty. Don’t wait until the whole herd is coughing and wheezing before regretting it. Prevention is the surest way to protect your profits this season. (Source: Zhang Weiguang)