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Asparagopsis taxiformis inhibits ruminal methane (CH 4) production due to its bromoform (CHBr 3) content. The immersion of A. taxiformis in edible vegetable oils allows the extraction and stabilization of the highly volatile CHBr 3 in the oil phase. The objectives of this study were to explore the effects of adding sunflower oils with increasing concentrations of CHBr 3 on in vitro ruminal methanogenesis and biohydrogenation. Five batches of 48-h in vitro incubations were performed in 14 fermentation bottles, using rumen inocula collected shortly after the slaughter of young crossbred bulls and 1 g of dry matter (DM) from a total diet of mixed feed without added oil (control) or with 60 μL of sunflower oil per gram of DM as the substrate. The treatments were the CHBr 3 content in the oil added: 0 μg (B0), 25 μg (B25), 50 μg (B50), 75 μg (B75), 100 μg (B100), and 150 μg (B150) of CHBr 3 per gram of substrate DM. Organic matter (OM) degradability, total gas, CH 4 , volatile fatty acids (VFA), long-chain fatty acids, and dimethyl acetals (DMA) were analyzed at the end of each incubation. Data were analyzed with a model considering the treatments as the fixed effect and the run as a random block and using orthogonal contrasts. Degradability of OM was higher in the control group and was unaffected by CHBr 3 concentration. Total gas production per gram of degraded OM was unaffected by treatments and averaged 205 ± 29.8 mL/g. Methane (mL) production decreased linearly with increasing CHBr 3 concentrations, with 33%, 47%, and 87% reductions for B75, B100, and B150, respectively. Total VFA concentration was unaffected by oil inclusion but was reduced by 20% in CHBr 3 -containing treatments, although without any dose-response pattern. The molar percentage of acetate decreased linearly, whereas propionate and butyrate increased linearly with the increasing CHBr 3 dosage. Including oil in the diet decreased the branched-chain fatty acids and DMA content. Increasing CHBr 3 concentrations did not affect branched-chain fatty acids, but linearly increased most of the identified DMA. Adding oil to the control diet increased the 18:2n-6, whereas increasing the concentration of CHBr 3 had no effect on 18:2n-6 but decreased linearly the 18:0 and increased the trans -18:1 isomers. The results obtained provide evidence that oil immersions of A. taxiformis can successfully inhibit ruminal production of CH 4 in vitro at doses of 100 and 150 μg/g DM, and simultaneously modulate biohydrogenation. [ABSTRACT FROM AUTHOR]

Abstract: Thirty-two Merino Branco ram lambs were used to evaluate the effects of basal diet and soybean oil supplementation on growth, carcass and meat quality and fatty acid composition of longissimus thoracis muscle. The lambs were submitted to four diets: ground and pelleted lucerne; ground and pelleted lucerne plus 10% soybean oil; concentrate; concentrate plus 10% soybean oil. Lambs were slaughtered after 7 weeks of trial. Lambs fed lucerne had higher intake and lower carcass weight. Intake decreased and carcass weight increased with oil supplementation in lucerne. Carcass weight decreased with oil inclusion in concentrate. Muscle and muscle/bone ratio were higher on concentrate. Oil decreased muscle proportion. Basal diet and lipid supplementation had minor effects on meat quality traits. Consumer''s distinguished meat from oil supplemented lambs, but did not reveal any particular preference. The trans-octadeceonates and conjugated octadecadienoates isomers are strongly dependent of basal diet and oil exacerbates the differences. The predominant trans-octadecenoate was 18:1 trans-11 in lucerne and 18:1 trans-10 in concentrate. The main conjugated octadecadienoic isomer was 18:2 cis-9, trans-11 in both basal diets. Oil increased 18:2 cis-9, trans-11 only in lucerne and 18:2 trans-10, cis-12 in concentrate. Lucerne fed lambs showed low ratio n-6/n-3 fatty acids. [Copyright &y& Elsevier]

Abstract: Forty Merino Branco ram lambs were used to study the effects of initial diet and duration of supplementation with a conjugated linoleic acid (CLA) promoting diet, on carcass composition, meat quality and fatty acid composition of intramuscular fat. The experimental period was 6 weeks. The experimental design involved 2 initial diets (commercial concentrate (C); dehydrated lucerne (L)), and 2 finishing periods (2 and 4 weeks) on dehydrated lucerne plus 10% soybean oil (O). Data were analysed as a 2×2 factorial arrangement with initial diet and time on finishing (CLA promoting) diet as the main factors. The lambs were randomly assigned to four groups: CCO; COO; LLO; LOO according to the lamb’s diet fed in each period. Lambs initially fed with concentrate showed higher hot carcass weights (11.2 vs 9.6kg) than lambs fed initially with lucerne. The increase of the duration of finishing period reduced the carcass muscle percentage (57.4% vs 55.5%) and increased the subcutaneous fat percentage (5.67% vs 7.03%). Meat colour was affected by initial diet. Lambs initially fed with concentrate showed a lower proportion of CLA (18:2cis-9, trans-11 isomer) (0.98% vs 1.38% of total fatty acids) and most of n−3 polyunsaturated fatty acids than lambs initially fed with lucerne. Initial diet did not compromise the response to the CLA-promoting diet and the proportion of 18:2cis-9, trans-11 in intramuscular fat increased with the duration of time on the CLA-promoting diet (1.02% vs 1.34% of total fatty acids). [Copyright &y& Elsevier]

Thirty-two Merino Branco (MB) ram lambs were used to evaluate the effects of lucerne particle size and soybean oil supplementation in growth, carcass and meat quality and fatty acid composition of longissimus thoracis muscle. The lambs were divided into four groups and submitted to four diets: conditioned hay of lucerne; conditioned hay of lucerne plus soybean oil; ground and pelleted lucerne; and ground and pelleted lucerne plus soybean oil. Lambs were weighed weekly and slaughtered after 6 weeks of trial. Hay fed lambs showed lower intake, lower average daily weight gain and lower slaughter and carcass weights. Dietary oil decreased intake, especially for pellets, reducing lambs growth rate and slaughter and carcass weights. Physical form of the diet and lipid supplementation had minor effects in carcass and meat quality traits. The results of oil inclusion were not conclusive for meat sensory attributes. Fatty acid composition was strongly affected by treatments and the high number of significant interactions showed that the effect of oil inclusion on fatty acid composition was highly dependent on forage particle size. With oil supplementation, C18:1 trans-11 and C18:2 cis-9 trans-11 increased, but this effect was more pronounced with hay. Linoleic acid also increased but this effect was larger in pellets. The ratio n-6/n-3 fatty acids was lower for hay. It increased with oil supplementation and, with pellets, the value was above the suggested threshold of 4. [Copyright &y& Elsevier]

The effects of dietary inclusion of Cistus ladanifer L. (CL) and a vegetable oil blend were evaluated on growth performance, carcass and meat quality of fifty four lambs that were assigned to 9 diets, corresponding to 3 levels of CL (50, 100 and 200 g/kg DM) and 3 levels of oil inclusion (0, 40 and 80 g/kg DM). Treatments had no effects on growth rate. Oil depressed dry matter intake (P = 0.017), carcass muscle (P = 0.041) and increased (P = 0.016) kidney knob channel fat. Chemical and physical meat quality traits were not affected by treatments. Off-flavour perception was higher for 8% of oil (P < 0.001). The level of 100 g/kg DM of CL inclusion improved meat stability after 7 days of storage. Supplementation with linseed and soybean oils (2:1) was a good approach to improve meat nutritional value from feedlot lambs, increasing total n-3 PUFA. [ABSTRACT FROM AUTHOR]

Abstract: An excessive lipid content in embryo cells is a consequence of embryo culture in the presence of serum which is suggested to be responsible for their high susceptibility to cryopreservation. The objective of the present study was to examine the effects of supplementing serum-containing culture media with trans-10 cis-12 conjugated linoleic acid (10t,12c CLA) on embryo lipid accumulation and its subsequent cryopreservation. Abattoir-derived oocytes were matured and fertilized in vitro (IVF=day 0). On day 1, presumptive zygotes (n =3390) were randomly placed in: (I) (MS), granulosa cell monolayer cultured with M199 and 10% serum; (II) (SCLA), granulosa cell monolayer cultured with M199, 10% serum and 100μM 10t,12c CLA and (III) (SOF), modified synthetic oviduct fluid, where embryo culture proceeded for 8 days. Cleavage rates or D7/D8 embryo quality did not vary among treatments. D7/D8 embryo production rate was significantly (P <0.001) lower in SOF (17.9±1.6%) than in groups MS (29.8±2.5%) and SCLA (27.8±2.0%). After cytoplasmic lipid droplets observation under Nomarski microscopy, classified embryos were the leanest when cultured in SOF, intermediate in SCLA and the fattest in MS (P <0.02). Post-thawing intact blastocyst rates where significantly higher in the SCLA group (84.7±4.1%) than in SOCS (50.3±4.8%, P =0.0007) or SOF (65.3±6.9%, P =0.03) groups. Post-thawing re-expanding rates were significantly lower when embryos were cultured in MS (34.7±3.7%) than in SCLA (63.7±5.3%, P =0.0006) or SOF (49.0±4.6%, P =0.04). Moreover, re-expanding rates were lower (P =0.05) in SOF than in SCLA cultured embryos. These results clearly show that addition of CLA to serum-containing media reduced lipid accumulation during in vitro culture and significantly improved cryopreservation survival. [Copyright &y& Elsevier]