Leal Diego F, Muro Bruno B D, Nichi Marcilio, Almond Glen W, Viana Carlos H C, Vioti Geovanna, Carnevale Rafaella F, Garbossa Cesar A P
Department of Animal Reproduction, FMVZ-USP Campus, São Paulo, SP, Brazil.
North Carolina State University, Raleigh, NC, USA.
Anim Reprod Sci. 2019 Jun;205:70-77. doi: 10.1016/j.anireprosci.2019.04.005. Epub 2019 Apr 16.
The feeding of diets with greater energy content than that needed for body maintenance following mating is believed to reduce embryonic survival in pigs. In swine operations, therefore, feed intake is often restricted during the first and second week of pregnancy to reduce embryo mortality. There is thought to be a relationship between feeding diets that result in energy intake that is greater than that needed for body maintenance and embryonic death. This relationship is associated with lesser than typical progesterone (P4) concentrations when feeding diets with greater energy content due to increased hepatic clearance. There is no consensus, however, as to whether feeding should be restricted during early pregnancy to avert this possible detrimental effect. Thus, the aim of this systematic review is to assess the effect in sows and gilts of feeding diets with different energy contents post-mating on embryonic survival, evaluating when possible, the relationship of a greater energy intake and P4 concentrations on embryonic survival. An electronic search was conducted of the PubMed, Science Direct, Scopus, Web of science, and Scielo databases during June 2018. A total of 109 articles were retrieved, and of these, only 16 articles were selected after applying the selection criteria. There was no negative effect of a greater feed intake than that needed for body maintenance after breeding in 75% of the experiments. Results from 35% of the experiments indicated feeding early pregnant sows a diet with greater energy content than that needed for body maintenance resulted in augmented embryonic death. In 66.7% of the experiments, in which there was assessment of P4 concentration, there was no negative effect of feeding after farrowing a diet with greater energy than that needed for body maintenance. In conclusion, it appears that restricted feed intake in early pregnancy is no longer relevant when there are modern prolific dam lines utilized in swine production enterprises because dietary energy of as great as 54 MJ ME/day had no detrimental effect on embryo survival.
交配后饲喂能量含量高于维持身体所需能量的日粮被认为会降低猪的胚胎存活率。因此，在养猪生产中，通常在妊娠的第一周和第二周限制采食量，以降低胚胎死亡率。人们认为，导致能量摄入量高于维持身体所需能量的日粮与胚胎死亡之间存在关联。由于肝脏清除率增加，饲喂能量含量较高的日粮时，这种关联与低于正常水平的孕酮（P4）浓度有关。然而，对于妊娠早期是否应限制饲喂以避免这种可能的有害影响，目前尚无共识。因此，本系统评价的目的是评估交配后给母猪和后备母猪饲喂不同能量含量日粮对胚胎存活率的影响，并在可能的情况下，评估较高能量摄入量与P4浓度对胚胎存活率的关系。2018年6月，对PubMed、Science Direct、Scopus、Web of science和Scielo数据库进行了电子检索。共检索到109篇文章，其中只有16篇文章在应用选择标准后被选中。在75%的实验中，繁殖后采食量高于维持身体所需量没有负面影响。35%的实验结果表明，给妊娠早期母猪饲喂能量含量高于维持身体所需量的日粮会导致胚胎死亡增加。在66.7%评估P4浓度的实验中，分娩后饲喂能量高于维持身体所需量的日粮没有负面影响。总之，当养猪生产企业使用现代高产母系时，妊娠早期限制采食量似乎不再适用，因为日粮能量高达54 MJ ME/天对胚胎存活率没有不利影响。
