What are the main factors affecting the fattening results of finishing pigs?
There are many factors affecting pig fattening, and the factors are both interrelated and mutually influencing. In essence, they can be divided into two aspects: genetic and environmental. Genetic factors include breed and type, growth and development patterns, early maturity, etc. Environmental factors include feed, feeding level, environmental conditions of the pig house and the health status of the pig herd, etc.
(1) The influence of breed and type on the fattening results of finishing pigs
The breed and type of pigs have a great influence on pig fattening. This is because different breeds of pigs have different growth and development patterns, and their nutritional requirements and feed quantities differ at different stages of the entire fattening period. Imported breeds, such as Large White pigs, Landrace pigs, Duroc pigs, Hampshire pigs, etc., are lean-meat type pigs. Under feeding conditions with concentrated feed and a high nutritional level, their fattening results are better than those of local breed pigs, they gain weight faster, and the fattening time is shorter. However, under medium and low nutritional level feeding conditions based mainly on green and coarse feed, the weight gain speed of foreign breeds is inferior to that of local breeds, and the fattening results are also poorer. Therefore, in order to improve fattening results, different fattening methods should be adopted for pigs of different breeds and types.
(2) The influence of crossbreeding on pig fattening performance
Using heterosis is one of the effective measures to improve the results of finishing pigs. This is because hybrid offspring have strong vitality, fast growth and development, high daily weight gain, and improved feed utilization rate, reducing feeding costs. However, the decisive factor for fattening results lies in an effective crossbreeding combination. Generally, foreign breeds are used as the sire and local pig breeds of our country as the dam. The heterosis rate for weight gain speed of the offspring is 10%-20%, and the heterosis rate for feed utilization is 5%-10%. Practice has proved that three-breed crossbreeding is better than two-breed crossbreeding.
(3) The influence of sex and castration on pig fattening results
Sex and castration both have a certain influence on fattening results. Practice has confirmed that castrated boars and sows gain weight faster than uncastrated ones, have higher feed utilization rates, enhanced fat deposition, improved meat quality, gentler temperament, and increased appetite. After castration, sexual function disappears, the catabolic process weakens, the anabolic process strengthens, and the absorbed nutrients can be more converted into fattening and meat growth. According to reports, the weight gain speed of castrated boars is 10% higher than that of uncastrated ones, and the fat content of castrated sows is 7.6% higher than that of uncastrated ones. Feed utilization rate and dressing percentage are both higher than those of uncastrated pigs. Some foreign breeds or improved breeds, because of relatively late sexual maturity, have little effect of young sows on fattening, so only boars are castrated and sows are not castrated during fattening. In recent years, with the development of pig-raising science and technology, the fattening period of pigs has been shortened. It is believed that fattening young boars without castration is superior to castrated boars and sows in terms of weight gain speed, feed utilization, carcass lean meat rate, etc., and is conducive to reducing production costs.
(4) The influence of birth weight and weaning weight on pig fattening results
Under normal circumstances, the greater the birth weight of piglets, the stronger their vitality, the faster their growth speed, and the greater their weaning weight. The greater the weaning weight, the faster the fattening weight gain, the less feed consumption, and the better the fattening results. Because temperature rises, feed intake decreases, and feed utilization rate and daily weight gain decline. Generally, a floor area of 0.8 sq m per finishing pig is sufficient. Too little also affects pig fattening, especially in winter, when heat dissipation is fast, maintenance requirements need to increase, and feed is wasted extra. In addition, diseases directly or indirectly affect finishing pigs to varying degrees. Therefore, during the pig fattening process, good environmental conditions should be created for the pigs, and efforts should be made to eliminate various factors unfavorable to pig fattening, in order to achieve ideal fattening results.