What is the best backfat range of the gilt breeding period?

Sow fat body condition is closely related to its reproductive performance, and backfat is the most direct reflection of sow body condition. Some studies have shown that the reproductive performance of the first fetus of gilt is important to the reproductive performance of the subsequent parity, while the backfat of gilt during the breeding period has a great impact on the reproductive performance of the first fetus.

With the development of large-scale and standardization of pig industry, large-scale pig farms began to use backfat apparatus to accurately regulate the backfat of sows. In this study, the backfat measurement of the gilt and the first and fetal litter performance were calculated, so as to find out the optimal backfat range of the gilt breeding period and provide a theoretical basis for guiding the gilt production.

1 Materials and Methods

1.1 Source of experimental pigs

Test in Shanghai pudong new area a scale pig farm, choose from September 2012 to September 2013 about 340 grams of gilt (American pig descendants) as a research object, choose in the sow when the second estrus, and determine the backfat, and the first litter, production, nest weight, nest, weak size reproductive performance data statistics (excluding poor health, incomplete data).

1.2 Test equipment and determination method

Determination was performed using a portable multifunctional B-superdiagnostic instrument. According to GB10152-2009, the measurement accuracy of B-type ultrasound diagnostic instrument (type KS107BG) is verified. When measuring, let the pig stand quietly naturally, and choose the right vertical backfat thickness (P2 point) at the back midline 5cm from the back of the pig as the measurement point, to avoid the deviation of the measurement caused by the back bow or waist collapse.

1.3 Data statistics

Raw data were first processed and analyzed with Excel tables, followed by ANOVA with SPSS20.0 software, and all data were expressed as mean ± standard deviation.

2 Results analysis

Table 1 shows the relationship between backfat thickness and the performance of first litter of gilts. In terms of litter size, the backfat of about gram gilt at P2 ranged from 9 to 14 m m, with the best litter performance ranging from 11 to 12 m m. From the point of view of live litter, the backfat was in the range of 10 to 13 m m, with the best performance at 12mm and 1 O live litter.35 Head.

From the perspective of the total nest weight, the backfat is heavier in the range of 11 to 14 m m, and the best performance is achieved in the range of 12 to 13 m m. For litter weights, the difference between the backfat groups was not significant (P & gt; O.05), but the thicker the backfat, the greater the average litter weight. From the perspective of weak weight rate, when the backfat is within 10~14mm, the weak weight rate is below 16, and is significantly lower than that of other groups (P & lt; 0.05), indicating that the backfat (9mm) and too thick (15mm) will cause a significant increase in the weak weight rate of sows (P & lt; O.05)。

3 Discussion

The fat condition condition of gilt is one of the important indicators to determine whether it can be matched. Studies have shown that too thin sows will seriously affect the normal development of follicles and ovulation, and even affect the embryo attachment in the uterus, resulting in reduced mating rate and conception rate; and overfertilization will lead to endocrine dysfunction and reduced level of basal metabolism, thus affecting estrus and mating of sows.

Through comparison, Luo Weixing found that the reproductive indicators of the middle group were generally higher than those of the backfat thick group, so it was very important to maintain the moderate fat condition when breeding. When Fangqin used B ultrasound to measure 100kg gilts, she found that the corrected backfat range between 11.OO~11.90mm was the earliest (P & lt; 0.05).

According to the results, the number of piglets produced at 1 O to 14 m m, total litter weight, litter head weight and weak litter rate were excellent, and the best reproductive performance was obtained at 11 to 13 m m. However, thin backfat (9mm) and too thick (15mm) often lead to the decline of litter performance, litter (head) weight and increased weak litter rate, which directly lead to the decline of the production performance of gilts.

In production practice, we should timely grasp the backfat situation of gilts, and timely adjust the fat situation according to the back fat situation. Before breeding, overweight sows should be controlled in time, which can not only save feed cost but also improve the breeding performance of the sows; lean sows should strengthen feeding management and timely feeding, and overweight sows still adjust or have growth retardation and dysplasia sows should be eliminated as soon as possible to improve the production performance and breeding benefit of the whole pig farm.