Effects of forage rape at various levels on growth performance, carcass traits, meat quality, rumen fermentation and rumen microbiota of Hu lambs

Abstract

Background: The objective of this study was to investigate the effects of forage rape ( Brassica napus ) in total mixed ration (TMR)-based diet on growth performance, carcass traits, meat quality, rumen fermentation and rumen microbiota of Hu lambs. Methods: A total of 50 Hu lambs (20.86 ± 3.00 kg, three-month-old) were randomly allocated into five dietary treatments: Ctrl, T1, T2, T3 and T4 with 0, 10%, 20%, 30% and 40% of forage rape, respectively. Each treatment had 10 replicates of one lamb each and the study lasted for 60 days. Results: The results showed that T2, T3 and T4 increased the average daily gain (ADG) and decreased the feed conversion ratio (FCR) significantly compared with Ctrl and T1 ( P < 0.05). Moreover, the final body weight and ADG were increased, and the FCR were decreased linearly ( P < 0.05) along with increasing forage rape levels. The relative weight of liver was increased in T3 and T4 compared with Ctrl ( P < 0.05). With increasing forage rape levels, the relative content of intramuscular heptadecenoic acid and α-linolenic acid, and the composition of various amino acids in the muscle of lambs were increased linearly ( P < 0.05), while ruminal concentration of ammonia nitrogen was decreased linearly ( P < 0.05). No difference on carcass traits, meat quality or ruminal profile of short-chain fatty acids were observed among groups ( P > 0.05). In addition, the inclusion of forage rape altered the rumen microbial community, and increased the relative abundance of cellulolytic bacteria and short-chain fatty acid producers, including genera Family_XIII_AD3011_group and Anaerovorax in T1, Succiniclasticum and Fibrobacter in T2, Ruminiclostridium_5 in T3, and members of family Lachnospiraceae and genus Shuttleworthia in T4. Conclusion: TMR included with forage rape could improve growth performance, meat nutritional value and rumen microbial community of Hu lambs.

The effects of fermented pineapple residue on growth performance, meat quality, and rumen microbiota of fattening Simmental bull

“…Furthermore, Succiniclasticum abundance has been positively correlated to feed efficiency (Auffret et al, 2020 ; Clemmons et al, 2020 ). Daghio et al ( 2021 ) and Du et al ( 2021 ) found that Succiniclasticum was positively correlated to body weight, which is consistent with our results. Ma et al ( 2021 ) observed that Succiniclasticum was positively related to NH 3 -N, isobutyrate, and isovalerate levels, which is inconsistent with our results.…”