In vitro rumen fermentation pattern: insights from concentrate level and plant oil supplement.

The addition of oil to ruminant diets and oil fatty acid profiles are major factors that negatively affect ruminal fermentation, while increased forage level attenuates the adverse effects. The aim of this study was to determine the effects of oil source supplementation and concentrate level in the diet on in vitro ruminal fermentation kinetics. Pomegranate, garlic or sunflower oils were added (2 % dry matter (DM) basis) to the diets containing 40 % or 60 % (DM basis) concentrates. In vitro gas production parameters, pH, ammonia nitrogen concentration and total protozoa count were measured. Additionally, metabolizable energy (ME), short-chain fatty acid (SCFA) production and organic matter digestibility (OMD) were determined. Rumen fermentation parameters and protozoal population counts were analyzed as a completely randomized design with a 2  × â€¯3 factorial arrangement of treatments, and gas production parameters were analyzed as a 2  × â€¯3 factorial arrangement in a randomized block design. The results showed that the HCPO (high (60 %) concentrate diet containing pomegranate oil) and HCSO (high (60 %) concentrate diet containing sunflower oil) diets produced the highest (5.40 mg dL - 1 ) and lowest (2.61 mg dL - 1 ) concentrations of NH 3 -N ( p > 0.01 ), respectively. Total protozoa count tended ( p = 0.07 ) to be highest in HCPO and lowest in HCSO diets (5.10 vs. 4.81 Log 10 g - 1 digesta). No interaction effects between the concentrate level and oil source were found on in vitro gas production parameters, pH, estimated ME, SCFA and OMD, and Entodinium and Diplodinium populations ( p > 0.05 ). It is concluded that dietary supplementation with highly unsaturated oil from three different sources at 2 % level (DM basis) had no apparent effects on in vitro ruminal fermentation patterns.

Interaction effect of ruminal undegradable protein level and rumen-protected conjugated linoleic acid (CLA) inclusion in the diet of growing goat kids on meat CLA content and quality traits.

The aim of the present study was to determine the effects of dietary rumen undegradable protein (RUP) level and rumen-protected conjugated linoleic acid (rpCLA) on meat fatty acid (FA) profile, chemical compositions and colour parameters of growing kids. Thirty-two Kurdish goat kids (13·06 ± 1·08 kg body weight) were fed diets differing in RUP level (low = 250 v. high = 350 g/kg of dietary crude protein) supplemented either with 15 g/kg of rpCLA or 12 g/kg of hydrogenated soyabean oil (HSO) for 80 d. Interaction of dietary rpCLA and RUP level had no effect on hot carcass weight, dressing and cut percentage, and meat chemical composition and colour parameters. Meat total SFA, MUFA and PUFA concentrations were not influenced by experimental diets, whereas kids fed diets supplemented with rpCLA had lower meat total SFA and higher PUFA concentrations compared with those fed diets supplemented with HSO. The concentration of meat trans-11-8 : 1 was not influenced by rpCLA supplementation, RUP level and their interaction. Kids fed diets containing rpCLA supplementation had higher meat total CLA and cis-9, trans-11-CLA and trans-10, cis-12-CLA isomers compared with those fed diets containing HSO supplementation. Desaturase indexes of C14, C16 and C18 were not influenced by rpCLA supplementation, RUP level and their interaction. It is concluded that supplementing growing kids' diets with RUP and 15 g/kg of rpCLA not only decreased meat fat content but also increased some FA considered to be of potential benefit to human health.