Comparison of the Retention Rates of Synthetic and Natural Astaxanthin in Feeds and Their Effects on Pigmentation, Growth, and Health in Rainbow Trout (Oncorhynchus mykiss).

The coloring efficiency and physiological function of astaxanthin in fish vary with its regions. The aim of this study was to compare the retention rates of dietary astaxanthin from different sources and its effects on growth, pigmentation, and physiological function in Oncorhynchus mykiss. Fish were fed astaxanthin-supplemented diets (LP: 0.1% Lucantin® Pink CWD; CP: 0.1% Carophyll® Pink; EP: 0.1% Essention® Pink; PR: 1% Phaffia rhodozyma; HP: 1% Haematococcus pluvialis), or a diet without astaxanthin supplementation, for 56 days. Dietary astaxanthin enhanced pigmentation as well as the growth of the fish. The intestinal morphology of fish was improved, and the crude protein content of dorsal muscle significantly increased in fish fed with astaxanthin. Moreover, astaxanthin led to a decrease in total cholesterol levels and alanine aminotransferase and aspartate aminotransferase activity in plasma. Fish fed on the CP diet also produced the highest level of umami amino acids (aspartic acid and glutamic acid). Regarding antioxidant capacity, astaxanthin increased Nrf2/HO-1 signaling and antioxidant enzyme activity. Innate immune responses, including lysozyme and complement systems, were also stimulated by astaxanthin. Lucantin® Pink CWD had the highest stability in feed and achieved the best pigmentation, Essention® Pink performed best in growth promotion and Carophyll® Pink resulted in the best flesh quality. H. pluvialis was the astaxanthin source for achieving the best antioxidant properties and immunity of O. mykiss.

Butyrate Glycerides Protect against Intestinal Inflammation and Barrier Dysfunction in Mice.

This study investigates the attenuating effects of butyrate glycerides (BG) on intestinal inflammatory responses and barrier dysfunction induced by LPS stimulation. An initial dose-response test was carried out to identify the optimal dose of BG for further testing. The mice were given intragastric administration of BG at different doses followed by lipopolysaccharide (LPS) intraperitoneal injection. The small intestinal morphology and cytokine mRNA expression were measured. With 1.5 g/kg BW BG administration, it was possible to alleviate the injury of duodenal morphology, attenuate ileum villus height reduction and promote IL-10 mRNA expression. Therefore, the optimal dosage of 1.5 g/kg BW BG was selected for the main experiment. The ultrastructure image of jejunum and ileum epithelial cells, mRNA expression, the level of cytokine and immunofluorescence in the ileum were analyzed. The results showed that BG maintain the ileac brush border, tight junction structures and protein expression. BG attenuated the increased inflammatory cytokines, TLR4 and JNK mRNA expression. Taken together, 1.5 g/kg BW BG administration maintained intestinal barrier function and reduced intestinal and body inflammation responses induced by LPS in mice. The mechanism by which BG alleviated intestinal inflammatory response and maintained intestinal barrier function may be related to the JNK signaling pathway.

Effects of a mixture of mono-glycerides of butyric-, capric-, and caprylic acid with chlortetracycline on the growth performance, intestine morphology, and cecal microflora of broiler birds.

This study aimed to investigate the effects of a mixture of mono-glycerides of butyric-, capric-, and caprylic acid (MMG) on the growth performance, intestinal morphology, and cecal microflora of broilers. A total of 960 male Arbor Acre broilers were offered basal diets with or without Chlortetracycline additive (CA) at 500 g/t, and MMG at 3,000, 1,000, or 650 g/t, with 8 replicates of 20 birds per treatment. The results confirmed 500 g/t CA with/without 1,000 g/t MMG increased the average daily weight gain (ADG) of birds compared to the control group 1 during the 42-d experimental period (P < 0.05). Comparing to the control group 1, 500 g/t CA with either 650 g or 1,000 g/t MMG or 1,000 g MMG alone increased the ADG of birds during the late growth stage (22-42 d) (P < 0.05). On d 42, the serum triglyceride levels were higher (P < 0.05) in groups supplemented with CA and CA + 1,000 g/t MMG comparing to the control group; while urea nitrogen level was higher in the control group comparing to the rest of treatment groups Compared to the control group 1, 1,000 g/t MMG alone without CA decreased the abundance of Faecalibacterium and Bacteroides but increased the abundance of Escherichia/Shiegella. About 500 g/t CA alone treatment group had higher abundance of Lactobacillus comparing to the rest of groups. In conclusion, dietary supplement with MMG showed beneficial efficacy on the growth and intestinal function of broilers, demonstrating the potential value of MMG to poultry industry. In terms of dosage, the current trial shows that 3,000 g/t (1-21 d) and 1,000 g/t (22-42 d) MMG without CA was the appropriate dietary supplemented rate for broilers. And the mixed use of 500 g/t CA and 1,000 g/t MMG was benefit for broilers at 22 to 42 d.

Effects of inorganic trace minerals replaced by complexed glycinates on reproductive performance, blood profiles, and antioxidant status in broiler breeders.

This study was conducted to investigate the effects of replacing inorganic trace minerals (ITM) with organic trace minerals (OTM; complexed glycinates) on reproductive performance, blood profiles, and antioxidant status in broiler breeders. A total of 648, 23-week-old healthy broiler breeders (ZhenNing), with similar body weight (1.40 ± 0.002 kg), were randomly divided into 4 groups with 6 replicates in each group (27 hens/replicate) and fed the respective experimental diets for 14 wk (including 2 wk for adaptation). The experimental treatments consisted of T1: Cont., commercially recommended levels of ITM (Cu, Zn, Fe, and Mn sulfates); T2: Mix, half trace minerals (TM) were provided from ITM and half from OTM (glycinates); T3: M-OTM, TM were provided from glycinates and reduced to 70% of T1; T4: L-OTM, TM were provided from glycinates and reduced to 50% of T1. The results showed that commercial level of inorganic trace minerals replaced by low-dose complexed glycinates (T3 and T4) exhibited no significant effects on laying performance, 50% ITM replaced by complexed glycinates (T2) numerically improved laying rate by 1.23% than cont. treatment (T1). Broiler breeders fed complexed glycinates tended to produce more qualified eggs (P = 0.05) in T3, with better yolk color (P < 0.01) and eggshell thickness (P = 0.05) in T2 treatment. Replacement of low-dose complexed glycinates reduced fertilization rate (P < 0.01), while it did not affect hatchability. There were no significant differences in serum reproductive hormones such as estrogen and progesterone among the treatments. Serum total protein, albumin, and phosphorus were increased respectively with the replacement of ITM by low-dose OTM from complexed glycinates (P < 0.05). Total liver antioxidant capacity in M-OTM and L-OTM treatment was higher than that of Cont. and Mix treatments (P < 0.01). In conclusion, replacement of high levels of ITM by lower levels of OTM in the form of complexed glycinates is beneficial for egg quality and liver antioxidant status in broiler breeders during the peak laying period.

Effects of Replacing Inorganic with Respective Complexed Glycinate Minerals on Apparent Mineral Bioavailability and Deposition Rate in Tissues of Broiler Breeders.

The study was conducted to evaluate the effects of replacing inorganic trace minerals (ITMs) with respective low-dose complexed glycinate minerals (CGMs) on their bioavailability and retention during peak laying period of broiler breeders. In this experiment, 648 ZhenNing broiler breeders (23 weeks old) were randomly allocated to four treatments with six replicates (27 birds/replicate) and fed for 14 weeks including 2 weeks adaptation period. The treatments were T1-ITM, commercially recommended levels of ITMs (Cu, Zn, Fe, and Mn sulphates); T2-MIX, half of the minerals were supplemented with ITMs and half with CGMs; T3-L-CGMs, minerals were supplemented with CGMs (50% level of T1); and T4-M-CGMs, minerals were supplemented with CGMs (70% level of T1). The results showed that birds fed on ITM had lower bioavailability of Fe, Mn, and Zn (P < 0.05) than those fed on L-CGMs, but the highest (P < 0.01) bioavailability of Cu was found in those fed on MIX. Mineral retention (in serum, muscle, bone, and tissues) was not affected by reducing supplementation levels of trace minerals up to 50% of ITMs, but Zn (in serum, liver, kidney, heart, and albumen) and Fe (in serum and the yolk) retention was negatively affected (P < 0.05). In conclusion, replacing dietary ITMs with low-dose complexed glycinate minerals increases the apparent bioavailability of Fe, Mn, and Zn without compromising the mineral retention rates in most of the tissues tested.