Age and Diet Affect Gene Expression Profile in Canine Skeletal Muscle

We evaluated gene transcription in canine skeletal muscle (biceps femoris) using microarray analysis to identify effects of age and diet on gene expression. Twelve female beagles were used (six 1-year olds and six 12-year olds) and they were fed one of two experimental diets for 12 months. One diet contained primarily plant-based protein sources (PPB), whereas the second diet contained primarily animal-based protein sources (APB). Affymetrix GeneChip Canine Genome Arrays were used to hybridize extracted RNA. Age had the greatest effect on gene transcription (262 differentially expressed genes), whereas the effect of diet was relatively small (22 differentially expressed genes). Effects of age (regardless of diet) were most notable on genes related to metabolism, cell cycle and cell development, and transcription function. All these genes were predominantly down-regulated in geriatric dogs. Age-affected genes that were differentially expressed on only one of two diets were primarily noted in the PPB diet group (144/165 genes). Again, genes related to cell cycle (22/35) and metabolism (15/19) had predominantly decreased transcription in geriatric dogs, but 6/8 genes related to muscle development had increased expression. Effects of diet on muscle gene expression were mostly noted in geriatric dogs, but no consistent patterns in transcription were observed. The insight these data provide into gene expression profiles of canine skeletal muscle as affected by age, could serve as a foundation for future research pertaining to age-related muscle diseases

The role of dietary fibre in pig production, with a particular emphasis on reproduction

Abstract Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locally-produced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems, particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production. Of particular potential value is the opportunity to use crude fibre concentrates as ‘functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates

Características químicas e valores energéticos de farelos de soja do oeste e sudoeste do Paraná Chemistry characteristics and energetics values of soybean meals

Foi realizado um estudo para determinar a variabilidade de características químicas e valores energéticos de farelos de soja (FS) do oeste e sudoeste do Paraná. Foram estudadas 40 amostras colhidas em 10 processadores e distribuidores durante quatro meses consecutivos. Houve diferenças (P<0,05) entre os teores de matéria seca (MS) dos farelos de soja (FS) analisados. O FS 10 apresentou menor (P<0,05) teor de MS (86,72%) em relação aos FS 2, 4, 5, 6 e 9 (88,96, 90,60, 89,19, 89,08 e 88,72%, respectivamente). O FS 4 teve menor conteúdo de Ca (0,31%), enquanto os FS 5 e 7 mostraram os maiores teores de Ca (0,36 e 0,36%, respectivamente). Ocorreram diferenças (P<0,05) entre os valores de energia metabolizável verdadeira (EMVn) calculados, com o FS 8 apresentando a maior concentração (2,65Mcal kg-1) e os FS 5 e 10 os menores teores de energia calculados (2,51 e 2,50Mcal kg-1, respectivamente). Pode-se concluir que a composição química dos farelos de soja das regiões oeste e sudoeste do Paraná apresenta pouca variação e, exceto para a fibra em detergente neutro, fibra em detergente ácido, ferro e manganês, os valores encontrados são próximos daqueles citados na literatura.<br>A study was conducted to determine the variability on chemical and nutritional characteristics of soybean meal from the West and Southwest Paraná state. Forty samples of soybean meal were collected in ten different processors and distributors during four months consecutively. There were differences (P<0.05) among the dry matter (DM) in samples of soybean meal analyzed. The soybean meal 10 had less (P<0.05) level of DM (86.72%) compared with soybean meals 2, 4, 5, 6 and 9 (88.96, 90.60, 89.19, 89.08 and 88.72%, respectively). The soybean meal 4 showed less content of Ca (0.31%), while the soybean meals 5 and 7 had higher levels of Ca (0.36 and 0.36, respectively). The calculated TMEn value of soybean meal 8 was higher (P<0.05) than soybean meals 5 and 10 (2.65 versus 2.51 and 2.50Mcal kg-1, respectively). The chemical composition of soybean meal from the West and Southwest Paraná state is homogenous and near that found in scientific literature, except for neutral detergent fiber, acid detergent fiber, iron and manganese