Adipocyte cellularity in different adipose depots in bulls of seven Spanish breeds slaughtered at two body weights

Abstract

The influence of body weight (BW) at slaughter and genotype on adipocyte size and number in the omental (OM), perirenal (PR), subcutaneous (SC) and intermuscular (IM) adipose tissues was studied in 168 bulls of Spain's local Asturiana, Avileñ a, Morucha, Parda Alpina, Pirenaica, Retinta, and Rubia Gallega cattle breeds. The young bulls were slaughtered at two BWs, 320 and 540 kg. The results obtained showed the higher amounts of lipids that accumulated between 320 and 540 kg BW (P , 0.001) to be ascribable primarily to adipose cell hypertrophy, i.e. larger adipocyte size, in the OM and PR depots (P , 0.001). In addition to hypertrophy, there was also an increase (P , 0.001) in the number of adipose cells, i.e. hyperplasia, in the SC and IM adipose depots. Significant differences were observed when comparing the different genotypes, with the Morucha, Retinta and Avileñ a breeds having the highest amount of adipose tissue and the largest adipocytes. The Asturiana and Rubia Gallega breeds had the lowest amount of adipose tissue and the smallest adipocytes. The Pirenaica and Parda Alpina breeds had intermediate values in between the two groups identified above. In short, the results were indicative of different lipid deposition patterns in the different breeds depending on the individual growth and maturation rates in each. Similar findings were made when comparing the different adipose tissue depots, with adipocyte hypertrophy being the main factor responsible for lipid accumulation in the OM and PR depots, as opposed to adipocyte hyperplasia in the SC and IM depots.

Body composition in mature Parda de Montaña and Pirenaica suckler cows

“…Although there were no statistical differences, the former dual purpose breed (PA) displayed slightly lesser contents of these fat depots than the hardy breed (PI). A similar trend was observed in young bulls of these breeds fed on a concentrate-based diet and slaughtered at 540 kg (5.4 vs. 5.5 kg for omental fat, 3.5 vs. 3.5 kg for KKCF, in PA and PI, respectively) (Alzón et al, 2007).…”

Adiposity and adipogenic gene expression in four different muscles in beef cattle

“…Intensity of hyperplasia and hypertrophy processes are influenced by factors such as genotype, sex, age, feeding regimen, and the individual adipose tissue depot [38, 39, 41]. Then, the study of the size and number of adipocytes might help to elucidate the different contribution of hypertrophy and hyperplasia of adipose cells to lipid accumulation [42] and therefore, to better understand the relationship between those processes and the amount of fat stored in the tissues.…”

Caracterización de la distribución del tamaño de los adipocitos para el estudio del tejido adiposo en producción animal

“…El conocimiento del tejido adiposo de los animales domésticos es de gran relevancia en producción animal dadas las implicaciones que tiene sobre el desarrollo y crecimiento de los animales, los resultados reproductivos, la calidad sensorial y nutricional de los productos y la eficiencia en la utilización de los recursos alimentarios, entre otros. Por ello, tanto el estudio de su formación (adipogénesis) como de su metabolismo (lipogénesis y lipólisis) son de gran importancia y han sido objeto de numerosos trabajos (Dodson et al, 2010), algunos de ellos relativos a nuestras poblaciones animales y sistemas de producción (Alzón et al, 2007;Soret et al, 1998).…”