選擇同窩豬中生長速度快的豬只。
Gilts should be in the fastest growing 50-60% of theircontemporary group.
生長速度快的豬女可以擁有較長的使用年限。
Adequate growth increases the probability of properreproductive development.
生長速度慢的豬女有可能出現(xiàn)初情期延遲的現(xiàn)象，并且在以后的飼養(yǎng)過程中問題較多。
Slow growing females (within a group) may have a delayed first estrus and may be lifelong problem breeders.
背膘
Backfat
背膘厚度對于后備母豬選擇是一個(gè)非常重要的指標(biāo)。
Backfat is important ifreplacement females are produced within the herd.
對于良種豬群，通過《聯(lián)邦國家豬群改進(jìn)指導(dǎo)方針》獲得合適的測量和調(diào)整標(biāo)準(zhǔn)。
Consult NSIFGuidelines for Uniform Swine Improvement to obtain proper measurement andadjustment criteria.
特定豬場的推薦背膘厚度會根據(jù)遺傳、環(huán)境和終端市場的需求而改變。
Recommended levelsof backfat are farm specificand may change due to genetics, environment, and end market.