Energy and protein requirements for maintenance of Texel lambs

Abstract

It can be hypothesized that the body composition characteristics of different sheep breeds affect their nutritional requirements. However, no study has yet been carried out to determine the nutritional requirements for maintenance of Texel purebred lambs, despite their growing importance in sheep meat production globally. Our objective was therefore to determine the energy and protein requirements for maintenance of Texel lambs. Thirty-four Texel lambs were used, all intact males that were weaned at 50 days old, and confined in individual pens. Two experiments were conducted, as follows. In Experiment 1, a digestibility assay was performed to determine the dietary energy value, in a 3×3 double Latin square design, in which lambs were submitted to three levels of feed restriction (0%, 55% and 70% of ad libitum feed intake). In Experiment 2, the energy and protein requirements for maintenance of Texel lambs from 21 to 40 kg BW were determined using a randomized block design, in which lambs were also submitted to three levels of feed restriction (0%, 55% and 70% of ad libitum feed intake). The requirements for net energy for maintenance (NEm), metabolizable energy for maintenance (MEm), net protein for maintenance (NPm) and metabolizable protein for maintenance (MPm) were determined. The digestibility of dry matter, energy, protein and metabolizability were similar between food restriction levels, averaging 74.4%, 75.5%, 80.3% and 0.636, respectively. The NEm determined for growing Texel lambs was 263 kJ/kg of the metabolic fasting BW (FBW), the MEm was 417 kJ/kg0.75 FBW and the efficiency of use of MEm was 0.63. In addition, the NPm was 1.24 g/day per kg0.75 FBW and the MPm was 2.98 g/day per kg0.75 FBW. The energy requirements of Texel lambs are different from those reported in the literature, possibly due to differences between breeds, diets and environmental effects, whereas the protein requirements are different from literature mainly due to methodological differences; further studies are need to address these aspects that affects the nutritional requirements for raising sheep from different breeds in different environments.

Dietary protein levels modulate the gut microbiome composition through fecal samples derived from lactating ewes

“…The lactating stage is critical for ewes and their lambs, as ewes require essential nutrition to support themselves and their lamb’s survival and health at this stage. The addition of proteins to daily diets improves the metabolic activity of ruminants ( 2 , 3 , 5 ) In the present study, we analyzed the effects of dietary proteins on the bacterial characteristics in fecal samples using 16S rDNA sequencing and metagenomic approaches. Our findings demonstrate that dynamic changes in fecal bacteria and their genes are strongly influenced by the levels of dietary proteins.…”

“…Several studies on fecal bacteria have been conducted in sheep (10,13) and cattle (14,15). Although previous investigations have confirmed the functional roles of dietary proteins in the growth and development of sheep (2,3,5), there are no reports on the impact of dietary proteins on fecal bacteria in the first 90 days of lactating after the parturition. In this study, we aimed to characterize the fecal bacterial community of Yunnan semi-fine wool sheep at the lactating stage, using 16S rDNA sequencing together with metagenomic approaches, based on growth data obtained after feeding with various levels of dietary proteins.…”

“…Breeders and researchers are exploring better ways to improve the productive traits (milk, meat and wool production) of sheep breeds through different strategies, but the sheep breed is a critical factor influencing productive traits ( 1 ). However, daily diets, including their sources and components, also affect sheep growth and health ( 1 , 2 ). Generally, sheep graze on pastures growing different types of plants such as grasses, clovers, and weeds.…”

“…During certain harsh periods of the year, sheep moved to temporary indoor rearing and were mostly fed with small amounts of concentrates and hay ( 1 , 3 ). Currently, the feeding system of sheep is changing significantly and gradually moving to an indoor-rearing mode ( 2 ). Therefore, determining the effects of nutrition on sheep-production during indoor rearing has become critical ( 2 , 3 ).…”

“…Currently, the feeding system of sheep is changing significantly and gradually moving to an indoor-rearing mode ( 2 ). Therefore, determining the effects of nutrition on sheep-production during indoor rearing has become critical ( 2 , 3 ).…”