Intramuscular fat has been reduced to below 1% of muscle weight in modern pigs through the genetic selection which has simultaneously harmed the sensory trait of pork because of a direct relationship between IMF and the formation of tenderness, juiciness, marbling, and the flavor of cooked meat [98]. fed LP diets were higher than pigs fed traditional diets, because the need for nitrogen for endogenous synthesis of non-essential AA to support protein synthesis may be increased when dietary CP is lowered. Overall, to address these concerns and give a better understanding of this nutritional strategy, this paper reviews recent advances in the study of LP diets for swine and provides some insights into future research directions. and species, thereby increasing PWD incidence [33]. Thus, reducing the amount of protein reaching the large intestine by selecting highly digestible protein ingredients or lowering the dietary protein level may help to alleviate PWD. Although a full description of protein sources is usually beyond the scope of this article, animal protein exhibits a superior feeding value than herb protein partly VERU-111 due to higher digestibility [34]; therefore fishmeal and whey powder often used in young pig diets. The CP level of common CSBM diets for weaned piglets in the nursery phase (i.e. from 7 to 20?kg body weight) commonly varies from 21% to 25% according to the hygiene situation of pig farms or production goals [35]. Many studies VERU-111 have investigated the extent of dietary CP reduction needed to effectively lower PWD. Yue and Qiao [6] reduced the dietary CP level from 23.1% to 18.9% of supplementing with FCAA and reported lower PWD and a simultaneous improvement in fecal consistency. A further reduction to 17.2% decreased growth performance despite addition of ((ETEC) challenge in the ileum of weaned piglets fed a 22.5% CP diet compared with those fed a 17.6% CP diet [42]. This result further confirmed that LP diets could alleviate alterations in intestinal morphology induced by pathogenic bacteria and maintain the normal digestion and absorption capacity of intestinal cells. However, further reduction by more than 4% resulted in a significant reduction in villous height in both duodenum and jejunum even though diets were supplemented with and [46]. A culture-independent method using denaturing gradient gel electrophoresis (DGGE) indicated that this numbers of and IV were lower in pigs fed 14% dietary CP than in 20% dietary CP with minimal impact on other bacteria populations [47]. Principally, it seemed that the dietary CP level influences the genus. Opapeju et al. [42] reported that in young pigs challenged with ETEC, reducing dietary CP can significantly lower the amount of ETEC in both ileum and colon. However, many other studies reported that changes in dietary CP content had no significant influence around the bacterial communities in all sections of the intestine under normal physiological conditions, because the microbiota can adapt to a certain extent following changes in dietary CP level [48]. Results of studies evaluating the effect of dietary CP level around the composition of microbiota are inconsistent. However, many of these studies were performed using the traditional culture-dependent or low throughput culture-independent methods and these methods are limited to detection of bacteria that can be cultured in vitro or are abundant in vivo. With the application of high-throughput sequencing, 16S rRNA gene sequencing has been widely used in biological studies and may help in developing VERU-111 a comprehensive understanding of the influence of dietary CP level on variation in intestinal bacteria. In a long-term feeding experiment (100 d), pyrosequencing of the V1-V3 region of the 16S rRNA gene showed a 3% reduction in dietary CP decreased the relative abundance of in the cecum and in the colon of growing pigs compared with a HP diet [49]. Moreover, the ileum and colon microbiota of finishing pigs were also influenced by dietary CP levels, where a moderate reduction of dietary CP Rabbit Polyclonal to CDH11 concentration (no more than 3%) improved the bacterial community structure in both the ileum and colon of finishing VERU-111 pigs; specifically increases in the proportion of Peptostreptococcaceae which are helpful in maintaining gut homeostasis [7]. Conventional wisdom suggested that adult mammals have a stable intestinal microbiota VERU-111 populace that is difficult to influence by dietary strategies in comparison to weaned piglets harboring unstable microbiota populations [50]. Additionally, previous studies focused on the changes of hindgut microbiota and neglected the effect of bacteria in the small intestine [51]. With the application of high-throughput sequencing, the microbial communities of different physiological stages and gut locations have provided evidence that.