Liu Guangfan, Su Fen, Zou Xingyue, Yang Xingming, Tian Liang
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
Anim Biosci. 2025 Jan;38(1):176-188. doi: 10.5713/ab.24.0270. Epub 2024 Oct 24.
This study aimed to assess the impact of a prolonged photoperiod on the growth performance and lipid metabolism of weaned piglets.
Twenty-four piglets weaned at 28 days of age were randomly dichotomized into two groups that were alternatively subjected to either long photoperiod (LP) group (16 L:8 D) or short photoperiod (SP) group (10 L:14 D) for 42days. Four replicates of three animals per replicates were used per experimental treatment.
Our results demonstrated that prolonged photoperiod increased piglet body weight, average daily weight gain (ADG), backfat thickness (BF), backfat index during the nursery period, and increased ADG, average daily feed intake (ADFI), and decreased the F/G of piglets during the experiment days 29 to 42. Meanwhile, we observed LP piglets' plasma melatonin, growth hormone and serotonin levels were decreased at 14 d and 42 d compared to SP piglets. Moreover, up-regulated mRNA or protein expression of PPARγ and CEBPα, and lower mRNA or protein expression of MTR1, ATGL, HSL, PPARα, and CPT1α, were observed in back subcutaneous fat of LP group compared with that of SP group. Significant increases were observed in the mRNA or protein contents of lipogenic genes, including C/EBPα, SREBP-1c, ACCα, and FAS, in the liver of LP piglets, whereas CPT1α and ACOX1 mRNA levels and PPARα and MTR1 protein expression were significantly downregulated in LP group compared to SP group. Extended photoperiod also increased lipid content in longissimus dorsi muscle that was associated with higher mRNA or protein levels of SREBP-1c, ACCα, FAS, Pref1, and LPL, decreased mRNA or protein contents of LeptinR, MTR1, HSL, and ACOX1.
Together, these findings suggest that there is an advantage, in terms of growth performance and fat deposition, in imposing a prolonged light program (16-h light/d) on nursery piglets to alleviate the negative aspects of weaning stress.
本研究旨在评估延长光照周期对断奶仔猪生长性能和脂质代谢的影响。
将24头28日龄断奶仔猪随机分为两组，分别交替接受长光照周期（LP）组（16小时光照：8小时黑暗）或短光照周期（SP）组（10小时光照：14小时黑暗），持续42天。每个实验处理使用4个重复，每个重复3头仔猪。
我们的结果表明，延长光照周期增加了保育期仔猪体重、平均日增重（ADG）、背膘厚度（BF）、背膘指数，并且在实验第29至42天增加了ADG、平均日采食量（ADFI），降低了仔猪的料肉比。同时，我们观察到与SP组仔猪相比，LP组仔猪在14天和42天时血浆褪黑素、生长激素和血清素水平降低。此外，与SP组相比，LP组背部皮下脂肪中PPARγ和CEBPα的mRNA或蛋白表达上调，而MTR1、ATGL、HSL、PPARα和CPT1α的mRNA或蛋白表达降低。LP组仔猪肝脏中包括C/EBPα、SREBP-1c、ACCα和FAS在内的生脂基因的mRNA或蛋白含量显著增加，而与SP组相比，LP组CPT1α和ACOX1 mRNA水平以及PPARα和MTR1蛋白表达显著下调。延长光照周期还增加了背最长肌中的脂质含量，这与SREBP-1c、ACCα、FAS、Pref1和LPL的较高mRNA或蛋白水平相关，降低了LeptinR、MTR1、HSL和ACOX1的mRNA或蛋白含量。
总之，这些发现表明，就生长性能和脂肪沉积而言，对保育仔猪实施延长光照程序（16小时光照/天）具有优势，可减轻断奶应激的负面影响。
