MANGEMENT OF SWINE (PIGS ) IN SUMMER SEASON As temperature and humidity rise you can expect to see high death rates in pigs ,decrease growth rate ,decrease in boar fertility, more embryonic deaths ,less ovulation rate, delayed oestrus in sows and gilts if the comfort of animals is not taken care off .
POINTS TO BE KEPT IN MIND :
Pig handling, inspection of water outlets ,care of cooling and ventilation system,trucking guidelines and plans for seasonal infertility.
Pig handling
Pay extra attention to the movement of animals. Keep the pigs calm, move them slowly. In addition, be certain to avoid loud noises and moving pigs too fast. Moving pigs in groups that are too large (more than five pigs) also causes pigs to become more excitable and hot. Try to avoid excessive stationary periods when moving & loading especially in hot weather. Consider changing the pig movement schedule to early in the day or late in the evening when it is cooler. Heat will increase the stress on an animal during movement.
Signs of pig stress to be aware of are:
Open mouth breathing, blotchy skin, vocalization ,stiffness, muscle tremors, increased heart rate, increased body temperature
Nursery and finisher
Inspect and maintain cooling and ventilation systems: Fans, drip-and-spray cooling systems, and air inlets should be checked to make sure they are functional. Take special care to check for worn fan belts that may dramatically reduce the ventilation rate. Also, the nozzles in drip-and-spray cooling systems may have become plugged with sediment from periods of inactivity. These nozzles should be checked and cleaned.
Provide adequate water: Water usage will increase for each type of animal in the summertime. A nursery pig will need 1 gallon per day and a finisher 5 gallons per day. Nipple waters should be checked for minimum flow rates to ensure that the animals can achieve their minimum water requirements.
Prevent overcrowding: Overcrowding of pigs will have a greater impact in the summer. Adequate space to reduce fighting and improve pig performance is more critical in warmer weather. Nursery pigs need 1.7 to 2.5 square feet per pig. In the finisher, space needs grow as the pig grows, starting at 5 square feet per pig at placement (50 kg) and ending with 8 square feet per pig at 100 kg to market.
Use care when trucking: When trucking animals, load and unload promptly and do not make stops. Animals should be wet prior to transport on hot days. Trucks should provide maximum ventilation, and using wet sand or wet shavings for bedding can be beneficial.
Breeding herd
Seasonal infertility is well documented. If your herd has historically had a seasonal infertility problem, take steps to reach your breeding target. This can be accomplished by breeding up to 40 percent more females, depending on the decline you see in farrowing rate. Breeding targets should increase gradually through May, June, July, and August and decline through September to a normal level. High temperatures reduce feed intake, which impairs the female’s ability to adequately recover from farrowing. This results in longer wean-to-estrus intervals and reduced ovulation rates.
Remember that keeping boars fertile is just as important as keeping the sow herd comfortable. Two weeks of exposure to 80-degree-plus Farenheit temperatures cause a dramatic increase in abnormal sperm and a reduction in motility. It will take the boar a minimum of four weeks to recover from heat stress. Boars may also become lethargic and have reduced libido during periods of hot weather. When temperatures rise, monitor the boars’ respiration rates. Normal respiration is 25 to 35 breaths per minute, and heat stress is 75 to 100 breaths per minute. When the boars’ respiration reaches 40 to 50 breaths per minute, intervene and take measures to cool the boars.
Feed consumption: Without question getting sows to maintain feed consumption or prevent it from decreasing during the summer months is the most critical management step for reducing the impact of heat stress and seasonal infertility. It is important during warm weather to maintain the breeding herd’s feed intake.
- Feed when temperatures are lowest: Feeding when temperatures are lowest in the early morning or evening can stimulate the sow’s appetite. To accomplish this, a change in work schedule is often required.
- Increase feeding frequency: Most producers experience a 10 to 15 percent increase in feed intake when they change from 2 to 3 times per day. The main thing to remember here is that when you increase the frequency of feeding, you decrease the amount that you feed each time. For example, if you are currently feeding 2.5kg twice a day (5.0 kg total), when you switch to feeding three times per day, you may want to offer the animals around 1.56kg at each feeding (5.0kg total). The reason this strategy works is based on the normal increase in body temperature that occurs after a sow consumes a meal.
Theoretically, there wouldn’t be as big an increase in a sow’s body temperature after she eats 1.56kg versus 2.5 kg due to less feed to be digested, etc
- Use fresh feed: Sows tend to be picky eaters, compared to most animals (contrary to popular belief). In warm conditions, feed is more likely to spoil, compared to cool conditions, especially if it contains high levels of fat. It is interesting to note that increasing the feeding frequency in conjunction with feeding slightly smaller meals at each feeding is actually an excellent way to keep feed fresh as well.
- Try liquid diets: This practice can be implemented during lactation; but because of the short period of time that sows are actually in lactation, it may be more beneficial to acclimate females to this change of diet during late gestation. However, wet feeding reduces the time that feed may stay in the trough and be fresh. Success may vary greatly between operations, but this strategy has been reported to boost sow feed intakes as high 15 percent.
- Add fat to the diet: As a result of poor feed intake, many sows are not able to meet the metabolic demands of lactation and revert to a negative energy balance. This factor probably accounts for most of the reproductive disorders during periods of elevated temperatures. One way ensure that sows are consuming enough energy, even though they are eating a smaller quantity of feed, is to add fat to the lactation diet. First, a diet containing high amounts of fat will become rancid more rapidly than a traditional diet with 1 to 2 percent fat. Sows will not eat rancid feed, and, therefore, feeding smaller quantities more often and smelling leftover feed in the sow feeder at each feeding should be a standard practice. Second, because sows are consuming less feed, dietary levels of essential vitamins and minerals will also need to be boosted to account for less feed consumed on a daily basis.
- Provide constant water: High ambient temperatures will increase water requirements, particularly for sows. Increased water consumption coupled with increased urinary water loss is an effective mechanism by which pigs lose body heat. A change in ambient temperature gives an increase of >50 percent in water consumption. Nursing sows need to consume 20-25 litres of water every day and gestating sows 10 to 12 lit. One rule of thumb is a water-to-feed ratio of 5:1. Cold water should be given in hot season.
Check and maintain ventilation: The first step in reducing the impact of heat stress on sow fertility is to make sure that ventilation systems are in good working order and are providing adequate ventilation. Pigs are more sensitive to the combined effects of heat and relative humidity than humans are, since they do not sweat, and it is important to consider heat indexes and activation temperatures of supplemental cooling systems.. These could include evaporative drip or spray cooling and circulating fans. Sprinkling is preferred to fogging, which uses smaller water droplets. Sprinkling cools the skin surface by wetting the skin and allowing the water to evaporate, whereas fogging cools the air and then the air must cool the skin.
Prenatal mortality: Mortality at this stage may be as high as 40 percent. The bulk of this embryo loss occurs during the first 2 to 3 weeks following breeding. Factors associated with embryo loss include stage of pregnancy, disease, age of dam, genetic factors, nutrition, external environment, intrauterine environment, and stress. The following steps to avoid increased embryo mortality should be taken throughout the entire year; however, during a critical time when pigs are under extreme heat-related stress, following these suggestions is imperative:
- Avoid late estrual inseminations: The simplest way to prevent late estrual inseminations is to ignore “target” number of inseminations and breed females totally on the basis on a strong standing heat response. Another way to reduce mistimed inseminations is to determine the average estrus length in your weaned sows, gilts, and repeat breeders and based on these averages, shorten the last insemination interval.
- Minimize unnecessary stress by mixing females only at weaning: Once fertilization occurs in the oviducts, pig embryos descend into the uterus very quickly; however, implantation does not occur until day 12 and full attachment until day 18. During this time, the pig is highly susceptible to stress factors, such as movement and temperature. If females are to be mixed, this should be performed on the day of weaning to prevent unnecessary stress on the animal. Any unnecessary stress following breeding can result in embryo detachment and loss.
- Refrain from, or even stop, moving females in gestation to different locations: After breeding and around day 30 of pregnancy, females can be moved to a different location; however, mixing sows and gilts any time during or following breeding greatly increases the chances of subsequent embryo mortality. Temperature changes are likely to elevate embryo mortality, and steps to prevent environmental extremes should be taken to avoid unnecessary stress during early pregnancy.
- Provide a good, level plane of nutrition before, during, and after breeding: Pre-mating nutritional status appears to be a greater determinant of embryo numbers and survival than the post-mating diet in gilts. This strategy requires “flushing” gilts with an extra 1 to 2 pounds of feed during the estrus cycle prior to mating. This can be attempted for sows as well, even though most post-weaned sows will voluntarily restrict their own feed intake. However, various studies have indicated that high feed intake during the first 30 days following breeding may also have a negative impact the embryo survival rates. Therefore, sows and gilts should be maintained on a level feed plane at or slightly above maintenance following breeding. There are no extra measures to take in feeding during periods of heat stress with the exception of ensuring that the female is consuming feed daily .
At the end I want to emphasise on
Maintain shed temperature
Transport the animals in early hours of day
Avoid unnecessary movement of pregnant animals
Provide good comfortable place to boar .
Feed three times in a day
Give plenty of water .
Dr Parvinder Kaur (9814652576)
parvinder.lubana@yahoo.com
Veterinary officer
NRDDL- JALANDHAR
PUNJAB
