Calcium salts of CLA improve availability of dietary CLA

Review: Effect of essential fatty acids and conjugated linoleic acid on the adaptive physiology of dairy cows during the transition period

Cows fed total mixed rations (silage-based) may not receive as much essential fatty acids (EFAs) and conjugated linoleic acids (CLAs) as cows fed pasture-based rations (fresh grass) containing rich sources of polyunsaturated fatty acids. CLA-induced milk fat depression allows dairy cows to conserve more metabolisable energy, thereby shortening the state of negative energy balance and reducing excessive fat mobilisation at early lactation. EFAs, particularly α-linolenic acid, exert anti-inflammatory and antioxidative properties, thereby modulating immune functions. Thus, combined EFA and CLA supplementation seems to be an effective nutritional strategy to relieve energy metabolism and to improve immune response, which are often compromised during the transition from late pregnancy to lactation in high-yielding dairy cows. There has been extensive research on this idea over the last two decades, and despite promising results, several interfering factors have led to varying findings, making it difficult to conclude whether and under what conditions EFA and CLA supplementations are beneficial for dairy cows during the transition period. This article reviews the latest studies on the effects of EFA and CLA supplementation, alone or in combination, on dairy cow metabolism and health during various stages around parturition. Our review article summarises and provides novel insights into the mechanisms by which EFA and/or CLA influence markers of metabolism, energy homeostasis and partitioning, immunity, and inflammation revealed by a deep molecular phenotyping.

Energy value of dry fat and stabilised rice bran for broiler chickens

1. The ileal digestible energy (IDE), metabolisable energy (ME) and nitrogen-corrected ME (MEn) of dry fat (DF) and stabilised rice bran (SRB) were determined in two experiments with broiler chickens using the regression method.2. Chickens were fed a common broiler starter diet from d 0 to 17 and experimental diets from d 17 to 22 post hatching. Three diets were prepared; a maize-soybean meal reference diet (RD) and two test diets containing either DF at 50 or 100 g/kg replacement (Experiment 1) or SRB at 100 or 200 g/kg replacement (Experiment 2) of the energy-contributing ingredients in the RD. In each experiment, 192 chickens were randomly allocated to one of three dietary treatments in a randomised complete block design, comprising eight replicate cages with eight birds per cage.3. In Experiment 1, the IDE, ME and MEn linearly increased (P < 0.001) with increasing DF concentrations, while in Experiment 2, the IDE, ME and MEn of the diets were not affected by dietary supplemental SRB. The regression-derived IDE concentration for DF and SRB were 25.30 and 14.88 MJ/kg DM, respectively. The respective ME and MEn estimates (MJ/kg DM) were 25.32 and 24.78 for DF; 14.38 and 13.36 for SRB.4. In conclusion, the current data showed that broiler chickens utilised between 77% and 79% and 68% to 76% of the gross energy (GE) in DF and SRB, respectively, and this suggested a strong potential for these ingredients as dietary energy sources for broiler chickens.

Nutrient intake and ingestive behavior of feedlot steers fed with licuri cake

The objective of this study was to evaluate the effects of the inclusion of different levels of licuri cake on the consumption of dry matter and nutrients and ingestive behavior of feedlot crossbred steers. Forty-four crossbred steers with an average age of 24 months and a mean live weight of 358.19 ± 41.57 kg were used in the study. The animals were aleatorically distributed in a completely randomized design made up of four treatments, with 11 animals used per treatment: the control treatment (without the inclusion of licuri cake in the diet) and treatment with the inclusion levels of 8.5, 17, and 25.5% of licuri cake, respectively, in the total dry matter of the diet. The inclusion of licuri cake influenced the intake of dry matter, crude protein, ether extract, neutral detergent fiber corrected for ash and protein, and non-fibrous carbohydrates corrected for ash and protein, each of them showing quadratic behavior. There was an effect of the tested diets on the time spent on food intake and number of idle periods, which presented a quadratic effect, with maximum and minimum values obtained for the inclusion levels of the licuri cake of 16.92% and 11.00%, respectively. There was no effect of the tested diets on the time spent on rumination and idleness. The feed efficiency of the dry matter, the duration of the feeding period, and the duration of the idleness period were influenced by the inclusion of the licuri tart in the diet, presenting a linear decreasing effect. There was an increasing linear effect for the number of feeding periods and the duration of rumination periods. Given the results obtained, it can be concluded that the licuri cake changes the consumption and behavioral parameters of feedlot steers, being recommended its use in up to 8.5% of inclusion in the total dry matter of the diet.

Qualidade seminal e perfil metabólico de caprinos alimentados com semente de linhaça na dieta

RESUMO O objetivo da presente pesquisa foi avaliar o efeito da inclusão de semente de linhaça na dieta sobre a qualidade seminal e o perfil metabólico de machos caprinos. Foram utilizados 16 machos da raça Saanen, distribuídos aleatoriamente em quatro grupos, recebendo níveis de inclusão de semente de linhaça (0, 4, 8 e 12%) na dieta, durante um período de 60 dias. As coletas e as avaliações seminais foram realizadas duas vezes por semana. Os animais foram submetidos a coletas quinzenais de sangue, durante todo o período experimental. Os dados foram avaliados por ANOVA e pela análise de regressão a 5% de significância. Houve comportamento cúbico para motilidade espermática progressiva, que apresentou o maior valor (82,30%) com a adição de 9,92% de semente de linhaça na dieta (P<0,05). Houve comportamento cúbico para concentração plasmática de triglicerídeos, e o nível de 8% de semente de linhaça na dieta apresentou média de 43,32mg dL-1, acima dos valores normais para a espécie caprina (P<0,05). A inclusão de semente de linhaça na dieta de machos caprinos proporcionou melhora na produção espermática e na qualidade seminal. No entanto, devem-se considerar os possíveis efeitos dos níveis superiores a 4% de semente de linhaça sobre o perfil metabólico dos animais.

The effect of supplementing rumen undegradable unsaturated fatty acids on marbling in early-weaned steers

The objective of this study was to determine if supplementation with a rumen undegradable unsaturated fatty acids (FA) source improved marbling deposition in early-weaned steers. All steers (Angus, = 23; Angus × Hereford, = 24) were weaned at 150 ± 5 d of age. Steers were blocked by BW and breed and then randomly assigned to either control (CON; average 1.5 kg of corn gluten feed [CGF], = 23) or isocaloric supplementation containing a rumen undegradable fat source (RUF; 200 g of Megalac-R added to an average of 1.06 kg of CGF, = 24) offered 5 d/wk for 110 d. All steers had ad libitum access to pastures throughout treatment and received supplements individually. Steer BW and blood samples were collected at 0, 55, and 110 d of supplementation, and real-time ultrasound measurements were collected at d 110. Following treatment, steers were transported to Oklahoma State University for finishing and subsequent harvesting at a commercial plant. All data were analyzed using the PROC MIXED procedure of SAS either as repeated measures or ANOVA depending on parameters. There were no significant changes in BW from the beginning of treatment to harvest due to treatment. Ultrasound data showed that RUF steers tended ( = 0.08) to have more i.m. fat than CON at d 110. Serum concentrations of FA showed a treatment × day interaction ( < 0.02) for 16:0, 18:0, 18:1-9, 18:2, 20:4, and total FA. These specific FA concentrations slightly increased in CON steers, but there was a more pronounced increase in the concentration of these FA across the supplementation period in RUF steers. Serum triglyceride and cholesterol concentrations were increased ( < 0.01) on d 55 and 110 in RUF steers compared with those in CON steers. Serum leptin concentration in RUF steers was greater ( < 0.01) than CON steers at d 110. After harvest, RUF carcasses had greater ( = 0.01) marbling scores than those of CON carcasses. All other carcass measures were similar between treatments. The percentage of total lipids was increased ( = 0.011) in steaks from RUF compared to CON. There was a decrease ( < 0.05) in adipocyte diameter in i.m. fat depot of RUF steers compared to CON. There was also a tendency ( = 0.06) for RUF steers to have a greater percentage of 20 to 30 μm adipocytes in their i.m. depot than CON steers. This study indicates that supplementation of unsaturated FA can positively impact marbling deposition in early-weaned steers without impacting other carcass measures.