Winter is the honey bee’s non-productive season. The colony’s main task during the winter is to withstand the cold and to reduce bee losses. Losses during the winter can restrict the colony reproduction in spring, even more the production in the next whole year. Thus, the evaluation of the colony’s overwinter ability by studying its cold-hardiness is crucial. The goal of this study was to determine the variation of the cold tolerance during the overwintering period and the major physiological responses to the cold climate. Samples were collected from the late October 2016 to March 2017 in Taian, China. The super-cooling points (SCPs), which ranged from –7.41 to –6.49 °C, were lower than the average daily lowest temperature (–4 °C) in January. The protein content first increased and then decreased during winter. Glycogen is a major energy source, and its content level declined sharply in the middle of overwintering. Glycerol and some low-molecular weight sugars and polyols (mannitol, sorbitol, and trehalose) were found to serve as the primary cryoprotectants for overwintering bees, as their contents accumulated significantly during the winter (P<0.0001). For the first time, this study investigated antifreeze protein, protein lethal (2) essential for life-like (l(2)efl), and vitellogenin protein (Vg) mRNA expression pattern in the overwintering period. The results indicate that seasonal super-cooling capacity is assisted by the accumulation of a complex mixture of winter specific metabolites. Our findings may help in integrated feeding and management of honey bees to increase winter survival.
The present study investigated the growth performance, immune status, gut morphology, and gut microflora modulation in growing-to-finishing pigs (n = 72; 24 pigs/group) after dietary supplementation with Bacillus subtilis (B. subtilis; two groups (experiment 1 (E1) and experiment 2 (E2): 63 and 98 days, respectively) and control (Ct, basal diet). The results revealed that both 1–98 d and 1–63 d groups significantly improved growth performance, including an increase in midtest body weight (MBW) , final body weight (FBW) , and average daily gain (ADG) and a decrease in the ratio of feed to gain (F/G) . There was an increase in serum IgG and SOD levels after supplementation with B. subtilis . Furthermore, B. subtilis potentiated the integrity of intestinal morphology (villus height (VH) and villus height/crypt depth (VH/CD) ) in growing-to-finishing pigs. The LEfSe analysis identified 11 and 13 biomarkers in the fecal samples of the 1–63 d group and 1–98 d, respectively. The gut microflora alterations of growth-finishing pigs suggested that dietary B. subtilis could promote gut health by altering the relative abundances of different bacterial communities. A correlation analysis showed that B. subtilis could regulate the functional network of the intestine microflora and their interactions with its host. Taken together, dietary B. subtilis supplementation had a positive influence on the growth performance, gut health, and the composition of gut microorganisms, suggesting that B. subtilis can be used as a functional probiotic candidate for application in the production of growing-to-finishing pigs. Practical Applications. The addition of probiotics in the diet can modulate intestinal health, improve the digestibility of nutrients, and thus, help improve the nutrient utilization and production performance of pigs. It is one of the ideal substitutes for antibiotics. This study will help us understand the function of B. subtilis in the regulation of pig intestinal health, so as to provide scientific basis for the rational use of probiotics in the future pig industry.
Selenium (Se) is an essential micronutrient for humans and animals and is a powerful antioxidant that can promote reproductive and immune functions. The purpose of this study was to evaluate the effects of supplemental dietary selenium-enriched yeast (SeY) on egg quality, gut morphology and microflora in laying hens. In total, 100 HY-Line Brown laying hens (45-week old) were randomly allocated to two groups with 10 replicates and fed either a basal diet (without Se supplementation) or a basal diet containing 0.2 mg/kg Se in the form of SeY for 8 weeks. The Se supplementation did not have a significant effect on egg quality and intestinal morphology of laying hens. Based on the 16S rRNA sequencing, SeY dietary supplementation effectively modulated the cecal microbiota structure. An alpha diversity analysis demonstrated that birds fed 100 mg/kg SeY had a higher cecal bacterial diversity. SeY dietary addition elevated Erysipelotrichia (class), Lachnospiraceae (family), Erysipelotrichaceae (family) and Ruminococcus_torques_group (genus; p < .05). Analysis of microbial community-level phenotypes revealed that SeY supplementation decreased the microorganism abundance of facultatively anaerobic and potentially pathogenic phenotypes. Overall, SeY supplementation cannot significantly improve intestinal morphology; however, it modulated the composition of cecal microbiota toward a healthier gut.
Objective: The growth of pigs involves multiple regulatory mechanisms, and modern molecular breeding techniques can be used to understand the skeletal muscle growth and development to promote the selection process of pigs. This study aims to explore candidate lncRNAs and mRNAs related to skeletal muscle growth and development among Duroc pigs with different average daily gain (ADG).Methods: A total of 8 pigs were selected and divided into two groups: H group (high-ADG) and L group (low-ADG). And followed by whole transcriptome sequencing to identify differentially expressed (DE) lncRNAs and mRNAs.Results: In RNA-seq, 703 DE mRNAs (263 up-regulated and 440 down-regulated) and 74 DE lncRNAs (45 up-regulated and 29 down-regulated) were identified. In addition, 1,418 Transcription factors (TFs) were found. Compared with mRNAs, lncRNAs had fewer exons, shorter transcript length and open reading frame length. DE mRNAs and DE lncRNAs can form 417 lncRNA-mRNA pairs (antisense, cis and trans). DE mRNAs and target genes of lncRNAs were enriched in cellular processes, biological regulation, and regulation of biological processes. In addition, quantitative trait locus (QTL) analysis was used to detect the functions of DE mRNAs and lncRNAs, the most of DE mRNAs and target genes of lncRNAs were enriched in QTLs related to growth traits and skeletal muscle development. In single-nucleotide polymorphism/insertion-deletion (SNP/INDEL) analysis, 1,081,182 SNP and 131,721 INDEL were found, and transition was more than transversion. Over 60% of percentage were skipped exon events among alternative splicing events.Conclusion: The results showed that different ADG among Duroc pigs with the same diet maybe due to the DE mRNAs and DE lncRNAs related to skeletal muscle growth and development.