The effects of supplementation of noni (Morinda citrifolia L.) fruit polysaccharides-rich extract on antioxidant status and immune function in cashmere goats.

This experiment was designed to examine the effects of a dietary supplementation of polysaccharides-rich noni (Morinda citrifolia L.) fruit extract (NFP) on the anti-oxidant enzyme activities, cytokines level, and expression of corresponding genes in blood of cashmere goats. Twelve castrated, 2-yr-old male cashmere goats (45.44 ± 3.30 kg of BW ± SD) were used in a 2 × 2 crossover design: the basal diet with or without (CON) supplementation of NFP at 4 g per kg DM (0.4%). Each period lasted for 29 d, including 1 wk for diet transition, 20 d for adaptation, and the last 2 d for sampling. The results showed that NFP supplementation increased (P < 0.05) the levels of nitric oxide, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), and the activities of catalase (CAT), glutathione peroxidase (GPx), thioredoxin reductase (TrxR), and total superoxide dismutase (T-SOD) in serum. The expressions of CAT, GPx4, TrxR, SOD1, IL-6, and TNF-α genes were upregulated (P < 0.05), whereas the levels of malondialdehyde (P = 0.015) and reactive oxygen species (P = 0.051) in serum were reduced. The body weight gain of goats was increased (P = 0.006) with a nonsignificant increase of feed intake with NFP supplementation. In conclusion, dietary NFP supplementation enhanced the antioxidant status and immune function in blood of cashmere goats.

Due to the limited pasture supply and the seasonal imbalance of nutrients in grazed pastures in China, cashmere goats are commonly raised in a confined yard-feeding system, which may result in oxidative stress from a lack of green pastures. Noni (Morinda citrifolia L.) fruit polysaccharides contain various biological compounds that function as anti-inflammatory, antitumor, and to enhance immune responses, hence likely to relieve oxidative stress in animals. Previous researches in our laboratory have shown that polysaccharides-rich extract from noni fruit (NFP) enhanced rumen fermentation in cashmere goats. This experiment was designed to evaluate the effect of NFP supplementation on serum antioxidant status and immune function in cashmere goats. The results showed that dietary supplementation of 0.40% NFP enhanced the immune signaling molecule levels and antioxidant enzyme activities by upregulating the expression of related genes in blood and reduced the levels of lipid peroxides and free radicals in serum, while mature goats improved body weight. Therefore, NFP could be a viable source of antioxidants for cashmere goats.

Palm oil protects α-linolenic acid from rumen biohydrogenation and muscle oxidation in cashmere goat kids.

BACKGROUND: In ruminants, dietary C18:3n-3 can be lost through biohydrogenation in the rumen; and C18:3n-3 that by-passes the rumen still can be lost through oxidation in muscle, theoretically reducing the deposition of C18:3n-3, the substrate for synthesis of poly-unsaturated fatty acids (n-3 LCPUFA) in muscle. In vitro studies have shown that rumen hydrogenation of C18:3n-3 is reduced by supplementation with palm oil (rich in cis-9 C18:1). In addition, in hepatocytes, studies with neonatal rats have shown that cis-9 C18:1 inhibits the oxidation of C18:3n-3. It therefore seems likely that palm oil could reduce both rumen biohydrogenation of C18:3n-3 and muscle oxidation of C18:3n-3. The present experiment tested whether the addition of palm oil to a linseed oil supplement for goat kids would prevent the losses of C18:3n-3 and thus improve the FA composition in two muscles, Longissimus dorsi and Biceps femoris. To investigate the processes involved, we studied the rumen bacterial communities and measured the mRNA expression of genes related to lipid metabolism in Longissimus dorsi. Sixty 4-month-old castrated male Albas white cashmere kids were randomly allocated among three dietary treatments. All three diets contained the same ingredients in the same proportions, but differed in their fat additives: palm oil (PMO), linseed oil (LSO) or mixed oil (MIX; 2 parts linseed oil plus 1 part palm oil on a weight basis). RESULTS: Compared with the LSO diet, the MIX diet decreased the relative abuandance of Pseudobutyrivibrio, a bacterial species that is positively related to the proportional loss rate of dietary C18:3n-3 and that has been reported to generate the ATP required for biohydrogenation (reflecting a decrease in the abundance of rumen bacteria that hydrogenate C18:3n-3 in MIX kids). In muscle, the MIX diet increased concentrations of C18:3n-3, C20:5n-3, C22:6n-3, and n-3 LCPUFA, and thus decreased the n-6/n-3 ratio; decreased the mRNA expression of CPT1ß (a gene associated with fatty acid oxidation) and increased the mRNA expression of FADS1 and FADS2 (genes associated with n-3 LCPUFA synthesis), compared with the LSO diet. Interestingly, compared to Longissimus dorsi, Biceps femoris had greater concentrations of PUFA, greater ratios of unsaturated fatty acids/saturated fatty acids (U/S), and poly-unsaturated fatty acids/saturated fatty acids (P/S), but a lesser concentration of saturated fatty acids (SFA). CONCLUSIONS: In cashmere goat kids, a combination of linseed and palm oils in the diet increases the muscle concentration of n-3 LCPUFA, apparently by decreasing the relative abundance of rumen bacteria that are positively related to the proportional loss rate of dietary C18:3n-3, by inhibiting mRNA expression of genes related to C18:3n-3 oxidation in muscle, and by up-regulating mRNA expression of genes related to n-3 LCPUFA synthesis in muscle, especially in Longissimus dorsi.