Conjugated linoleic acid (CLA) during gestation and lactation does not alter sow performance or body weight gain and adiposity in progeny

The objective of this study was to determine the long-term effects of conjugated linoleic acid (CLA) in pigs exposed to CLA during fetal and neonatal growth. Sows were fed a diet with 0.83% soy oil or 0.83% CLA-60 containing 60% active CLA isomers from either d 40 (group 1; CON n = 8, CLA n = 6) or d 75 (group 2; CON n = 8, CLA n = 8) of gestation through weaning on d 28. Within group 1, one male and one female piglet per litter (CON n = 6, CLA n = 5) were sacrificed within 24 hours of birth (d 0) and body weights recorded. Semitendinosus muscle, subcutaneous adipose tissue and organs, including heart, liver, lung, kidney, brain were weighed and tissue samples were frozen. Two average weight barrows and two gilts per litter were weaned and fed standard diets without added CLA until market weight. CLA did not alter sow’s feed intake during gestation or lactation, body weight or backfat thickness, and litter size and weight at birth (P > 0.05). CLA decreased newborn pig heart, but not backfat or semitendinosus muscle weights relative to their body weights (d 0). CLA decreased pre-weaning weight in selected piglets but this was not maintained post-weaning. CLA decreased total milk fat by 17% (P  0,05). Le CLA a diminué le poids du cœur du nouveau-né, mais pas le poids du gras dorsal ou du muscle semitendinosus par rapport au poids corporel (d 0). Le CLA a diminué le poids pré-sevrage des porcelets mais cet effet ne s’est pas maintenu en post-sevrage. La matière grasse totale du lait a été diminuée par CLA de 17 % (P < 0,01), ce qui a eu pour conséquence une augmentation relative de la quantité d’acides gras saturés et une diminution de la quantité relative d’acides gras insaturés du lait le 21e jour de lactation (P < 0,05). La diminution de la vitesse de croissance jusqu’à 14 jours pourrait être due à la faible teneur en lipides du lait des truies puisque la vitesse de croissance et le poids corporel des porcelets n’ont pas différé en post-sevrage. Le sérum des porcelets nouveau-nés soumis au CLA a diminué le nombre relatif de préadipocytes et n’a pas modifié le stockage de lipides dans les cellules stromales vasculaires en culture. Ces observations ont d’ailleurs été plus marquées chez les femelles que chez les mâles (PDiet = 0,04 ; PDiet ×  Gender = 0,04). Il ne semble pas y avoir d’effets bénéfiques à long terme sur la croissance et la composition corporelle au poids habituel d’abattage chez les porcs ayant reçu 0,5 % de CLA jusqu’au sevrage

Adipose depots differ in cellularity, adipokines produced, gene expression, and cell systems

The race to manage the health concerns related to excess fat deposition has spawned a proliferation of clinical and basic research efforts to understand variables including dietary uptake, metabolism, and lipid deposition by adipocytes. A full appreciation of these variables must also include a depot-specific understanding of content and location in order to elucidate mechanisms governing cellular development and regulation of fat deposition. Because adipose tissue depots contain various cell types, differences in the cellularity among and within adipose depots are presently being documented to ascertain functional differences. This has led to the possibility of there being, within any one adipose depot, cellular distinctions that essentially result in adipose depots within depots. The papers comprising this issue will underscore numerous differences in cellularity (development, histogenesis, growth, metabolic function, regulation) of different adipose depots. Such information is useful in deciphering adipose depot involvement both in normal physiology and in pathology. Obesity, diabetes, metabolic syndrome, carcass composition of meat animals, performance of elite athletes, physiology/pathophysiology of aging, and numerous other diseases might be altered with a greater understanding of adipose depots and the cells that comprise them-including stem cells-during initial development and subsequent periods of normal/abnormal growth into senescence. Once thought to be dormant and innocuous, the adipocyte is emerging as a dynamic and influential cell and research will continue to identify complex physiologic regulation of processes involved in adipose depot physiology

Lipid metabolism, adipocyte depot physiology and utilization of meat animals as experimental models for metabolic research

Meat animals are unique as experimental models for both lipid metabolism and adipocyte studies because of their direct economic value for animal production. This paper discusses the principles that regulate adipogenesis in major meat animals (beef cattle, dairy cattle, and pigs), the definition of adipose depot-specific regulation of lipid metabolism or adipogenesis, and introduces the potential value of these animals as models for metabolic research including mammary biology and the ontogeny of fatty livers.</p