Effects of dietary fish oil supplementation on performance, meat quality, and cecal fermentation of growing rabbits

Abstract

The objective of this study was to investigate the effect of dietary supplementation with fish oil on growth performance (during all fatening period), carcass characteristics and fatty acid (FA) profile of muscle and fat tissues (at slaughter), as well as cecal fermentation and ileal mucosa morphology of growing rabbits (at 30, 45, and 60 d of age). Two isonitrogenous and isoenergetic diets, only differing in their fat source, were formulated and provided each to 24 does (12 per diet) and their offspring during pregnancy and lactation. The control diet contained 4.59 g of n-3 per 100 g of total FA, and the enriched diet contained 14.9 g of n-3 per 100 g of total FA. From weaning (30 d of age) to slaughter (60 d), the litters (12 per diet; 8 kits each) continued fed the corresponding experimental diet. There were no differences ( > 0.05) between groups in ADFI, ADG and G:F ratio during the growing period. At slaughter, BW, full gastrointestinal tract weight, carcass yield, meat color and pH, drip loss percentage, content of scapular fat and tissue composition of the left hind leg were similar between groups ( > 0.05), but perirenal fat was lower ( = 0.020) and skin weight and abdominal fat tended to be lower ( = 0.055 and = 0.063, respectively) in enriched rabbits than in control ones. Total PUFA content in both LM and perirenal fat was greater ( = 0.021 and < 0.001, respectively) in enriched rabbits, that also showed lower n-6/n-3 ratios in LM (1.61 vs. 5.80; < 0.001) and perirenal fat (4.71 vs. 12.0; < 0.001) than those fed the control diet. Cecal concentrations of total VFA were greater ( < 0.001) in enriched than in control group at 30, 45 and 60 d of age, but diet did not affect ( ≥ 0.332) VFA profile, with the exception of a lower ( = 0.013) proportion of minor VFA (sum of isobutyrate, isovalerate, and valerate) in control group. Diet did not affect ( > 0.255) either pH and NH-N concentrations in the cecum or ileal morphology (crypt depth and villi length). The results showed that dietary fish oil supplementation enhanced beneficial long-chain n-3 FA and decreased n-6/n-3 ratio in rabbit meat and fat, being healthier for human consumption, without having negative effects on growth performance, cecal fermentation, and ileal morphology or carcass characteristics.

Improvements in the conception rate, milk composition and embryo quality of rabbit does after dietary enrichment with n-3 polyunsaturated fatty acids

“…In humans, Rosqvist et al (2014) also observed that fat deposits in the liver and visceral fat were lower with rich PUFA diets. Furthermore, some rabbit researchers concluded that with PUFA diets less carcass fat (Kowalska and Bielánski, 2009) or abdominal and perirenal fat (Rodríguez et al, 2017b) is obtained. All these findings would support the low weaning weight of kits of enriched does.…”

Feeding Agro-Industrial By-Products to Light Lambs: Influence on Meat Characteristics, Lipid Oxidation, and Fatty Acid Profile

“…The same method was used to analyze the FA profile of subcutaneous fat of the tail root. The extraction of lipids from feeds (concentrate samples; 200 mg) followed the procedure of Sukhija and Palmquist [21] as detailed by Rodríguez et al [22], and the preparation and identification of fatty acid methyl esters were conducted as described before.…”

Supplementation with Fish Oil Improves Meat Fatty Acid Profile although Impairs Growth Performance of Early Weaned Rabbits

“…Rabbit meat is a Mediterranean food that is considered to be especially appreciated by consumers for its low lipid and cholesterol content and the high biological value of its protein [1,2]. However, despite being a meat that offers excellent nutritive and dietetic properties, in practical dietary conditions, their n-6/n-3 polyunsaturated fatty acids (PUFA) ratio is frequently above the optimal values recommended for human consumption [3,4,5]. Usually, the most common sources of fat in feed formulation of fattening rabbits are tallow, lard, deodorized oleins, and sunflower oil [6], which are low in n-3 PUFA.…”

“…Usually, the most common sources of fat in feed formulation of fattening rabbits are tallow, lard, deodorized oleins, and sunflower oil [6], which are low in n-3 PUFA. The manipulation of the diet of rabbits has proved to be very effective in producing PUFA-enriched meat, making it relatively easy to achieve optimal values [4,7]. Fish oil (FO) is one of the most common animal sources of n-3 PUFA, as it contains higher PUFA amounts than seed oils [8].…”