| Wild forest musk deer is a national first-class protected animal,mainly distributed in mountain regions of Shaanxi,Sichuan and other provinces.The musk secreted by the musk gland of male forest musk deer.It is not only the first of the four animal spices,but also a precious Chinese medicine,which has high medicinal value and economic value.Due to destruction of habitats and hunting,the number of wild forest musk deer and musk production has declined sharply.In order to protect wild forest musk deer and increase musk yield,the captive breeding and scientific research of forest musk deer were carried out in the 1950 s,and some results were obtained.However,many studies are not standard and in-depth,especially the mechanism of musk secretion.Therefore,it is necessary to further explore the captive breeding technology and mechanism of musk secretion.In this study,a forest musk deer farm in Shaanxi Province was taken as the object to investigate and analyze the captive breeding of forest musk deer in 2018-2019.The expression of androgen synthesis related genes in musk gland of 4-month-old male forest musk deer was explored by high-throughput sequencing,bioinformatics,RT-q PCR,HE staining and IHC.The main research results were as follows:(1)The investigation showed that the current captive breeding of forest musk deer has distinctive characteristics.For example,captive breeding way is the "House-Playground" model.The diet of forest musk deer is composed of roughage and concentrate supplements.Feed demand is different at different stages,but the quality of roughage is very important.Generally,suppurative diseases caused by injuries are more common,gastroenteritis and gastrointestinal diseases caused by some parasites occur sporadically,and young forest musk deer are easily infected with mycoplasma pneumonia.In breeding management,the male to female ratio is 1:2,which can ensure that the twin rate is more than 80%,and the reproduction rate is more than 180%;The musk production is related to age,3～8 years old is the peak period of musk secretion,with an average of 11.84～18.74 g.(2)The 4-month-old male forest musk is not sexually mature,and HE staining showed that the seminiferous tubules of testis are not fully developed,there are no round spermatids,elongating spermatid,and mature spermatids.The musk gland is a typical glandular tissue,composed of many glandular ducts,and glandular cells are attached to the base of the glandular lumen.Then,A total of 33308 genes were annotated in the musk gland by transcriptome sequencing analysis.Compared with testis,we found 7018 differential expression genes in musk gland,of which 3581 genes were up-regulated and 3437 genes were down-regulated.GO and KEGG analysis showed that 15 differential expression genes were enriched in steroid hormone synthesis pathway,of which CYP11A1,CYP17A1 and HSD3 B genes were involved in androgen synthesis.RT-q PCR and IHC results showed that CYP11A1,CYP17A1 and HSD3 B genes were expressed in musk gland.More importantly,CYP11A1,a key rate-limiting enzyme of androgen synthesis,was significantly more expressed in musk gland than testis.The investigation displayed that the captive breeding technology of forest musk deer needs to be improved,and the way of standardized breeding is importance to the forest musk deer.Furthermore,the expression of androgen synthesis related genes indicated that there may be androgen synthesis signal pathway in musk gland.We speculated that the musk gland could regulate its development by producing androgens itself,and even affect the yield and quality of musk. |
