Effects of Different Iron Supplements on Reproductive Performance and Antioxidant Capacity of Pregnant Sows as Well as Iron Content and Antioxidant Gene Expression in Newborn Piglets.

To improve the reproductive performance of sows and the iron nutrition of newborn piglets, we studied the effects of dietary iron on reproductive performance in pregnant sows as well as antioxidant capacity and the visceral iron content of sows and newborn piglets. Forty pregnant sows were divided into four groups, the iron deficiency group (Id group) was fed a basic diet while sows in the treatment groups were fed diets supplemented with 200 mg/kg lactoferrin (LF group), 0.8% heme-iron (Heme-Fe group), or 500 mg/kg iron-glycine complex (Fe-Gly group). The results indicated that (1) different sources of iron had no significant effect on litter size, live litter size, and litter weight of sows; (2) the three additives improved iron nutrition in newborn piglets, with LF and Heme-Fe having better improvement effects; and (3) the addition of different iron sources improved the level of serum antioxidant biochemical indexes of sows and newborn piglets, and it can have an effect on gene level, among which lactoferrin has the best effect. Thus, adding LF, Heme-iron, or Fe-Gly to the diet of sows during the second and third trimester of gestation can improve the antioxidant capacity of the sows. The supplementation of LF in pregnant sow diets can also improve the antioxidant capacity and the iron nutrition of newborn piglets, with better additive effects than in Heme-Fe and Fe-Gly.

Effect of maternal lactoferrin supplementation on iron contents and anti-oxidant capacity in Dahe black Pig neonates.

Iron levels are closely related to animals' growth performance and anti-oxidant function. Lactoferrin (LF) is an iron-binding glycoprotein, which can promote the absorption of iron and regulate immune function. This study aimed to clarify the effect of maternal LF supplementation on the iron metabolism of Dahe piglets. Sixty sows (Dahe black, parity 3-4, no significant differences in body weight) were randomly assigned to five groups: control (basal diet with no iron supplementation), supplemented 100 (LF1 group), 200 (LF2 group), or 300 (LF3 group) mg LF/kg in the basal diet, and the basal diet supplemented with 100 (Fe-Gly group) mg Fe/kg as ferrous glycine (Fe-Gly). The serum anti-oxidant parameters of the sows and neonatal piglets were determined. The iron contents, anti-oxidant gene expression levels, and Fe-acquisition genes were detected in the liver, heart, spleen, and other neonatal organs. The results indicated that (1) the LF3 group of sows had the highest serum and colostrum iron contents (P < 0.05). The maternal LF significantly promoted the iron stores in the heart, liver, spleen, and lung of piglets compared with Fe-Gly. (2) The maternal LF increased serum glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) activities of sows. Compared with other groups, the total anti-oxidant capacity (T-AOC) activity of LF2 groups increased significantly (P < 0.05). (3) LF significantly increased piglet serum GSH-Px, T-SOD, and T-AOC activities (P < 0.05). (4) Gene expression levels of GSH-Px, and SOD in the duodenum and jejunum of the LF2 group were significantly higher than in the Fe-Gly group (P < 0.05), while the expression levels in the liver and heart were lower (P < 0.05). (5) The expression levels of hepcidin and LF in the liver and duodenum of the LF2 group were significantly higher than in the Fe-Gly group (P < 0.05). In conclusion, maternal LF supplementation showed remarkable effects on iron storage in neonatal piglets, and exhibited strong antioxidant activities, it is helpful to prevent the occurrence of iron deficiency, and improves the immune function of animals.

Comparative Analyses of Antibiotic Resistance Genes in Jejunum Microbiota of Pigs in Different Areas.

Antibiotic resistance genes (ARGs) are emerging environmental contaminants that threaten human and animal health. Intestinal microbiota may be an important ARGs repository, and intensive animal farming is a likely contributor to the environmental burden of ARGs. Using metagenomic sequencing, we investigated the structure, function, and drug resistance of the jejunal microbial community in Landrace (LA, Kunming), Saba (SB, Kunming), Dahe (DH, Qujing), and Diannan small-ear piglets (DS, Xishuangbanna) from different areas in Yunnan Province, China. Remarkable differences in jejunal microbial diversity among the different pig breeds, while the microbial composition of pig breeds in close areas tends to be similar. Functional analysis showed that there were abundant metabolic pathways and carbohydrate enzymes in all samples. In total, 32,487 ARGs were detected in all samples, which showed resistance to 38 categories of drugs. The abundance of ARGs in jejunum was not significantly different between LA and SB from the same area, but significantly different between DS, DH and LA or SB from different areas. Therefore, the abundance of ARGs was little affected by pig breeds and microorganism community structure, but it was closely related to geographical location. In addition, as a probiotic, Lactobacillus amylovorus is also an important ARGs producing bacterium. Our results revealed the antibiotic exposure and intestinal microbial resistance of farms in the study areas, which could provide basic knowledge and potential strategies for rational use of antibiotics and reducing the risk of ARGs transmission in animal husbandry.

Effects of Different Ambient Temperatures on Caecal Microbial Composition in Broilers.

Short-term or acute temperature stress affect the immune responses and alters the gut microbiota of broilers, but the influences of long-term temperature stress on stress biomarkers and the intestinal microbiota remains largely unknown. Therefore, we examined the effect of three long-term ambient temperatures (high (HC), medium (MC), and low (LC) temperature groups) on the gene expression of broilers' heat shock proteins (Hsps) and inflammation - related genes, as well as the caecal microbial composition. The results revealed that Hsp70 and Hsp90 levels in HC group significantly increased, and levels of Hsp70, Hsp90, IL-6, TNF-α, and NFKB1 in LC group were significantly higher than in MC group (p < 0.05). In comparison with the MC group, the proportion of Firmicutes increased in HC and LC groups, while that of Bacteroidetes decreased in LC group at phylum level (p < 0.05). At genus level, the proportion of Escherichia/Shigella, Phascolarctobacterium, Parabacteroides,and Enterococcus increased in HC group; the fraction of Faecalibacterium was higher in LC group; and the percentage of Barnesiella and Alistipes decreased in both HC and LC groups (p < 0.05). Functional analysis based on communities' phylogenetic investigation revealed that the pathways involved in environmental information processing and metabolism were enriched in the HC group. Those involved in cellular processes and signaling, metabolism, and gene regulation were enriched in LC group. Hence, we conclude that the long-term temperature stress can greatly alter the intestinal microbial communities in broilers and may further affect the host's immunity and health.

Characteristics of the Jejunal Microbiota in 35-Day-Old Saba and Landrace Piglets.

The balanced microbiological system is a significant hallmark of piglet health. One of the crucial factors affecting intestinal microbiota is the host's genetics. This study explored the difference in the diversity of jejunal microbiota between Saba (SB) and Landrace (LA) piglets. Nine Saba and nine Landrace piglets were fed with sow's milk until day 35. Jejunal contents were harvested for 16S rRNA sequencing. The birth weight, body weight, and average daily gain of Saba piglets were lower than those of Landrace piglets (p < 0.01). Firmicutes were the main phylum in Saba and Landrace piglets, and the Saba piglets had a higher (p < 0.05) abundance of Bacteroidetes compared with Landrace piglets. The two most abundant genera were Lactobacilli and Clostridium XI in the jejunum of Landrace and Saba piglets. Compared with Landrace piglets, the Saba piglets had significantly lower (p < 0.05) abundance of Veillonella, Streptococcus, and Saccharibacteria genera incertae sedis. The functional prediction showed that "d-glutamine and d-glutamate metabolism" and "one carbon pool by folate" pathways were enriched in Saba piglets, while "limonene and pinene degradation", "tryptophan metabolism", and "sulfur relay system" pathways were enriched in Landrace piglets. In summary, the growth performance was higher for Landrace piglets compared with Saba piglets due to their genetic characteristics. The rich diversity and fewer infection-associated taxa were observed in Saba piglets, partially accounting for their higher adaptability to environmental perturbations than Landrace piglets. Furthermore, different pig breeds may regulate their health through different metabolic pathways.

Correlation between Jejunal Microbial Diversity and Muscle Fatty Acids Deposition in Broilers Reared at Different Ambient Temperatures.

Temperature, which is an important environmental factor in broiler farming, can significantly influence the deposition of fatty acids in muscle. 300 one-day-old broiler chicks were randomly divided into three groups and reared at high, medium and low temperatures (HJ, MJ and LJ), respectively. Breast muscle and jejunal chyme samples were collected and subjected to analyses of fatty acid composition and 16S rRNA gene sequencing. Through spearman's rank correlation coefficient, the data were used to characterize the correlation between jejunal microbial diversity and muscle fatty acid deposition in the broilers. The results showed that Achromobacter, Stenotrophomonas, Pandoraea, Brevundimonas, Petrobacter and Variovorax were significantly enriched in the MJ group, and all of them were positively correlated with the fatty acid profiling of muscle and multiple lipid metabolism signaling pathways. Lactobacillus was significantly enriched in the HJ group and exhibited a positive correlation with fatty acid deposition. Pyramidobacter, Dialister, Bacteroides and Selenomonas were significantly enriched in the LJ group and displayed negative correlation with fatty acid deposition. Taken together, this study demonstrated that the jejunal microflora manifested considerable changes at high and low ambient temperatures and that jejunal microbiota changes were correlated with fatty acid deposition of muscle in broilers.

Effect of ethanolic extract of propolis on growth performance and plasma biochemical parameters of rainbow trout (Oncorhynchus mykiss).

This study was conducted to evaluate the effect of ethanolic extract of propolis (EEP) on growth performance and plasma biochemical parameters of rainbow trout (Oncorhynchus mykiss). Graded levels of EEP [0 (control), 1, 2, and 4 g kg(-1) diet] were fed to trout juveniles (mean weight 7.73 ± 0.17 g) for 10 weeks. Dietary EEP supplementation regardless of inclusion level significantly improved the specific growth rate of fish. Similarly, supplemental EEP generally improved the feed efficiency ratio and protein efficiency ratio, but no significant differences were observed between the 1 g kg(-1) EEP group and the control group. In addition, dietary EEP supplementation generally increased the plasma superoxide dismutase, lysozyme, total antioxidant capacity, glutathione peroxidase, and catalase activities, but decreased the plasma malondialdehyde level. The plasma triglycerides level was significantly lower in the 1 or 4 g kg(-1) EEP group as compared with the control group. Dietary EEP supplementation generally decreased the plasma aspartate aminotransferase and alanine aminotransferase activities, but increased the hepatic aspartate aminotransferase and alanine aminotransferase activities. These results indicate the potential to use the EEP as a growth promoter, hepatoprotective agent, and immunostimulant for rainbow trout.