Safety of dietary conjugated α-linolenic acid (CLNA) in a neonatal pig model

•Safety study of CLNA in pig.•No change of body composition and biochemistry parameters.•Perturbation of PUFA balance in tissues.

The aim of the present study was to perform a short-term safety evaluation of dietary mono-conjugated α-linolenic acid isomers (CLNA; c9-t11-c15-18:3 + c9-t13-c15-18:3) using a neonatal pig model. CLNA diet was compared with three other dietary fats: (1) conjugated linoleic acid (CLA; c9-t11-18:2 + t10-c12-18:2), (2) non-conjugated n-3 PUFA and (3) n-6 PUFA. Thirty-two piglets weaned at 3 weeks of age were distributed into four dietary groups. Diets were isoenergetic and food intake was controlled by a gastric tube. Mono-CLNA diet did not significantly change body or organ weight, carcass composition and most biochemical parameters including; glucose, cholesterol, triglycerides, creatinine, blood urea nitrogen, hepatic enzymes and electrolytes levels in blood (P ⩾ 0.09). Conversely, the n-3 PUFA composition of the brain, liver and heart decreased by 6-21% in the CLNA-fed group compared to animals fed nonconjugated n-3 PUFA (P < 0.01). Responses to dietary treatments were tissue-specific, with the liver and the brain being the most deprived in n-3 PUFA. Our results support that short-term intake of mono-CLNA is safe in neonatal pigs but n-3 PUFA reduction in tissues deserves to be further investigated before using long-term nutritional supplementation in pigs and other animal models and before moving to clinical trials.