Muñoz M, Fernández-Barroso M A, López-García A, Caraballo C, Nuñez Y, Óvilo C, González E, García-Casco J M
Centro de I+D en Cerdo Ibérico, Zafra (Badajoz), Spain; Departamento de Mejora Genética Animal, INIA, Madrid, Spain.
Centro de I+D en Cerdo Ibérico, Zafra (Badajoz), Spain; Departamento de Mejora Genética Animal, INIA, Madrid, Spain.
Animal. 2021 Dec;15(12):100408. doi: 10.1016/j.animal.2021.100408. Epub 2021 Dec 8.
Low protein diets supplied during the growing period of pigs can diminish their growth rate and increase the intramuscular fat (IMF) content which affects the sensorial and technological characteristics of the products. In the present study, the effects of a low protein diet supplied during the growing period of Duroc × Iberian crossbred pigs on several phenotypic traits and on liver and longissimus dorsi transcriptome were analysed at the beginning (EARLY) and at the end (LATE) of the growing period. Two experimental groups of 10 crossbred pigs each were fed two isocaloric diets with different protein content: control diet (C) with 16.5% protein and 0.8% lysine and low protein diet (LP) with 11% CP and 0.6% lysine. Animals fed LP diet have a slower growth than those fed C diet, but no effect of LP diet was observed on the IMF content. The transcriptomes of liver and longissimus dorsi were characterised and quantified through RNA-sequencing (RNA-seq). In liver, 134 and 480 differentially expressed annotated genes and new isoforms (DEGs) were detected between C and LP diets for EARLY and LATE animals, respectively. In muscle, 128 and 68 DEGs were detected at EARLY and LATE time-points. Functional interpretation revealed that LP diet may inhibit immune system molecules and processes in both tissues at EARLY stage. In liver, the DEGs mainly affect lipid and cholesterol metabolic processes, while in muscle, the expression changes would be involved in growth, development and meat quality. In conclusion, a low protein diet supplied during the growing period seems to slow down the growth of Duroc × Iberian crossbred pigs, but it also seems to affect multiple biological processes that could compromise the immune system of Duroc × Iberian crossbred pigs. Therefore, these results question the adequacy of this type of regime in Duroc × Iberian pigs that must be studied in greater depth before being implemented.
在猪的生长阶段提供低蛋白日粮会降低其生长速度，并增加肌内脂肪（IMF）含量，这会影响产品的感官和工艺特性。在本研究中，分析了杜洛克×伊比利亚杂交猪生长阶段开始时（早期）和结束时（晚期）提供低蛋白日粮对几种表型性状以及肝脏和背最长肌转录组的影响。两个实验组各有10头杂交猪，分别饲喂两种等热量但蛋白质含量不同的日粮：对照日粮（C）含16.5%蛋白质和0.8%赖氨酸，低蛋白日粮（LP）含11%粗蛋白和0.6%赖氨酸。饲喂LP日粮的动物生长速度比饲喂C日粮的动物慢，但未观察到LP日粮对IMF含量有影响。通过RNA测序（RNA-seq）对肝脏和背最长肌的转录组进行了表征和定量分析。在肝脏中，早期和晚期动物的C组和LP组日粮之间分别检测到134个和480个差异表达的注释基因和新异构体（DEG）。在肌肉中，在早期和晚期时间点分别检测到128个和68个DEG。功能解释表明，LP日粮在早期可能会抑制两个组织中的免疫系统分子和过程。在肝脏中，DEG主要影响脂质和胆固醇代谢过程，而在肌肉中，表达变化可能参与生长、发育和肉质形成。总之，生长阶段提供低蛋白日粮似乎会减缓杜洛克×伊比利亚杂交猪的生长，但也似乎会影响多个可能损害杜洛克×伊比利亚杂交猪免疫系统的生物学过程。因此，这些结果质疑了这种日粮模式在杜洛克×伊比利亚猪中的适用性，在实施之前必须进行更深入的研究。
