Integrated Transcriptome and Microbiota Reveal the Regulatory Effect of 25-Hydroxyvitamin D Supplementation in Antler Growth of Sika Deer

The level of plasma 25-hydroxyvitamin D (25(OH)D) is associated with the growth of the antler, a fast-growing bone organ of Cervidae. However, the benefits of 25(OH)D supplementation on antler growth and the underlying mechanisms remain unclear. Here, the antler growth profile and transcriptome, plasma parameters, rumen bacteria, and metabolites (volatile fatty acids and amino acids) were determined in sika deer in a 25(OH)D supplementation group (25(OH)D, n = 8) and a control group (Ctrl, n = 8). 25(OH)D supplementation significantly increased the antler weight and growth rate. The levels of IGF-1,25(OH)D and 1,25-dihydroxyvitamin D were significantly higher in the 25(OH)D group than in the Ctrl group, while the levels of LDL-C were lower. The levels of valerate and branched-chain amino acids in the rumen fluid were significantly different between the 25(OH)D and Ctrl groups. The bacterial diversity indices were not significantly different between the two groups. However, the relative abundances of the butyrate-producing bacteria (families Lachnospiraceae and Succinivibrionaceae) and the pyruvate metabolism pathway were higher in the 25(OH)D group. The transcriptomic profile of the antler was significantly different between the 25(OH)D and Ctrl groups, with 356 up- and 668 down-regulated differentially expressed genes (DEGs) in the 25(OH)D group. The up-regulated DEGs were enriched in the proteinaceous extracellular matrix and collagen, while the down-regulated DEGs were enriched in the immune system and lipid metabolism pathways. Overall, these results provide novel insights into the effects of 25(OH)D supplementation on the host metabolism, rumen microbiota, and antler transcriptome of sika deer.

Characterization of Cervus timorensis Velvet Antler and its Effect on Biofilm Formation of Candida Species

Oral biofilms comprise extracellular polysaccharides and polymicrobial microorganisms. The objectives of the study were to characterize the deer velvet antler (DVA) compounds and their effect on Candida species biofilm formation with the hypothesis that DVA inhibits the biofilm of Candida spp. Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry (LC-QTOF-MS) was conducted to characterize the DVA compounds. To study the effect of DVA on biofilm, Candida albicans ATCC MYA-4901 (ALT5), AIDS isolate (ALC2), oral cancer isolate (ALC3), C. dubliniensis ATCC MYA-2975, C. glabrata ATCC 90030, C. krusei 14 243, C. lusitaniae ATCC 34449, C. parapsilosis ATCC 22019, and C. tropicalis ATCC 13803 were inoculated with DVA in separate wells of a 96-well plate containing RPMI-1640 followed by 72 h incubation. A total of 45 compounds were detected in the DVA extract. C. lusitaniae exhibited a higher percentage of biofilm biomass reduction when treated with DVA extract (66.10% ± 5.33), followed by ALC3 (44.12% ± 6.24). However, C. glabrata, C. krusei, and C. parapsilosis showed no reduction in biofilm biomass after being treated with DVA extract. Most Candida strains also exhibited decreased total cell count when treated with DVA extract, except for ALC3 and C. krusei. ALT5 had the lowest total cell count (0.17 × 105 cells/mL) when cultured with DVA extract. In conclusion, DVA extract inhibits Candida spp. biofilm formation except for C. glabrata, C. krusei, and C. parapsilosis.

Velvet Antler Production and Hematological Changes in Male Sika Deers Fed with Spent Mushroom Substrate

At present, spent mushroom substrate (SMS) is a waste resource that is producing a pollution problem in China, and which has some use as animal feed or fertilizer, has not been assessed as a feed for deer. The purpose of this study is to expand the feed of male sika deer and reduce the feeding cost by using the waste resource of SMS. The 10% concentrated supplement was replaced with SMS and the feed intake, apparent digestibility, blood index and velvet production of male sika deer were measured. As the results showed, compared to the control group, the substitution of SMS for 10% of the concentrate supplement decreased the concentration of IgA (p < 0.01), replacing 10% concentrated supplement with SMS of Pleurotus ostreatus (SMS-MP) reduced the intake of organic matter (OMI) and improved the digestibility of ether extract (EE), while replacing 10% concentrated supplement with SMS of Flammulina velutipes (SMS-MF) had no effect on apparent nutrient digestibility, feed intake, velvet antler production, and biochemical indexes. In conclusion, SMS had no effect on serum biochemical indexes and the ratio of the feed weight of the deer supplement to the weight of velvet antler (p > 0.05). At the same time, SMS could reduce the feed consumption and improve the economy by using SMS as a waste resource.