9 июл. 2019 г. · Our underlying belief is that gilt management practices from birth have the potential to influence the future reproductive performance of .Introduction · Birth Traits that Determine the. · Effective Selection of the Most. Problems in fertility and longevity result when breeding occurs far outside the targets. Breeding under and overweight gilts appears most related to problems. These problems in body weight are related to issues with attainment of puberty and lifetime growth performance. Seasonal infertility is a reduction in fertility and fecundity in breeding pigs at a particular period of the year – usually summer and early autumn. It shows up mainly as two problems:
What are the different reproductive failures of gilts?
The problems most often encountered during the breed- ing phase include postweaning anestrus (delayed estrus), bleeding after service, estrous detection in recently weaned sows and gilts, delayed puberty in gilts, inadequate sexual behavior in boars, and copulation problems.
What causes infertility in sows?
Another cause of reduced fertility in the female is uterine infection. Bacteria may be introduced into the uterus at farrowing or at breeding. Most of the affected sows return to normal fertility by the next estrus unless a chronic urinary tract infection exists.
Why is low fertility common in the summer time with boars?
In addition, there may be reduced conception during the summer, caused partly by the seasonal effect on the sow and partly as a result of reduced semen quality and libido in the boar. A rise in infertility resulting from leptospiral infection may be present in some farms in the early autumn.
Can pigs become infertile?
Summer infertility in pigs can largely be attributed to heat stress but other factors tailor in, with awareness and management key to maximising production. Melanie Jenkins reports. Outdoor pig systems are highly susceptible to seasonal infertility, mainly due to the long days and high temperatures.
What are the health problems associated with gilt housing?
To avoid problems, gilt housing areas should be evaluated for auditory, air, and lighting conditions. Although limited data are available, it is generally assumed that problems in health, will be linked to reduced growth performance, delayed gilt puberty and perhaps problems in fertility.
How soon after breeding do gilts get pregnant?
In bred gilts with healthy embryos, pregnancy is recognized beginning on day 13 following AI and allows progesterone to remain elevated in blood for establishment and continuation of pregnancy until time of farrowing. Following breeding, factors that increase embryo loss and pregnancy failure are major concerns. As a result, attention has …
What are the environmental variables that affect gilt pool management?
Gilt pool management can be influenced by environmental variables that can affect the fertility and development and effective management must anticipate variation in the expected responses over seasons. Since final selection as “breeding eligible” is below 100%, the pool size must be increased to account for fertility and structural failures.
How does seasonal infertility affect fertility in pigs?
Entering the fall, most producers focus on the seasonal effects on fertility. In the northern hemisphere, seasonal infertility is associated with sows bred from July through September. This seasonal infertility results in fewer sows farrowed and fewer pigs born in early winter — November through January.