Ultrastructure of goat testes: intercellular bridge between germ cells.

The fine structure of intercellular bridge (ICB) of goat germ cells was studied using testicular samples fixed by perfusion. In the seminiferous tubules, the ICBs were observed between sister cells of spermatogonia, spermatocytes and spermatids. As a result of incomplete division of germ cells, the ICB first appeared as a midbody containing a remnant of the bundle of microtubules (spindle fibers). These microtubules then disappeared and were replaced by a shutter apparatus which was composed of multiple lamellar cisternae (bridge-partitioning complex). The inner part of the ICB was reinforced with a layer of electron dense mass (bridge density) which persisted up to the residual cytoplasm of spermiation. After complete reconstruction of the sister cells, the cisternae of the bridge-partitioning complex disappeared and the channel of the ICB was opened. Evidently (see electron micrographs), almost all of the cytoplasmic organelles could pass through the channel of the ICB. In the longitudinal section, the appearance of the ICBs between sister spermatogonia and between sister spermatocytes was observed as a double linear or drum shape, and that between sister spermatids was noticed as a horseshoe-like or concave formation. With the process of spermatogenesis, the ICBs gradually became widened and shortened. The functional significance of the ICB in the goat was discussed.     

Morphologic features of Sertoli cells in the intra-abdominal testes of cryptorchid dwarf goats

Light and electron microscopy revealed an age-related progression of alterations of Sertoli cells in the intra-abdominal and scrotal testes of unilaterally cryptorchid West African dwarf goats between the ages of 1 and 30 months. Alterations in the scrotal testis were, however, maturational and included differentiation of Sertoli-to-Sertoli cell junctional specializations, profusion of smooth endoplasmic reticulum, convolution of nuclear profiles, development of vacuolar components of the nucleolus, and an overall change in cell shape in response to proliferation of germinal cells. Corresponding features were observed in Sertoli cells of the contralateral intra-abdominal testis, but the cytoplasmic features were transient because the cells degenerated progressively. Early changes included segregation of the smooth endoplasmic reticulum into compact masses composed of dense, narrow cisternae, dilatation of the rough endoplasmic reticulum cisternae into large, irregular profiles, atrophy of the Golgi complex, and accumulation of lipid droplets and lipofuscin granules. Many of these organelles and inclusions no longer were obvious in Sertoli cells of 12- to 15-month-old goats; rather, intracellular vacuoles and dilated intercellular spaces had become common. In the 24- to 30-month-old goats, Sertoli cells in the intra-abdominal testis contained mostly microfilaments and basally located mitochondria with circular cristae in dense matrices. The Sertoli-to-Sertoli cell junctional specializations were structurally intact. These results indicated that, in spite of the unfavorable intra-abdominal environment, Sertoli cells of the intra-abdominal testis, before their degeneration, had developed features similar to those of the scrotal testis.     

波尔山羊与鲁北白山羊二元杂交对比试验

结果表明，以波尔山羊为父本组改良效果极为显著。杂种一代羊体型外貌明显倾向于父本—波尔山羊；初生、3月龄、6月龄、12月龄体重分别比同期当地白山羊提高59．5％、57．6％、66．8％、80．2％；屠宰率为46．12％，净肉率达42．8％．比鲁北白山羊高出5．6个百分点；羊肉品质明显改善。     

LncWNT3-IT affects the proliferation of Sertoli cells by regulating the expression of the WNT3 gene in goat testis

The proliferation and differentiation ability of testicular Sertoli cells directly affects spermatogenesis and male reproductive development. WNT proteins are involved in the regulation of cell proliferation, differentiation and spermatogenesis. Therefore, to study whether lncRNAs, which regulate the expression of WNT proteins during cell proliferation and differentiation, are worthwhile. In this study, testicular tissue from the Dazu black goat (Capra, goat, Chongqing, China) at neonatal time (less than 7 days old), early puberty time (45 days old) and sexual maturity time (90 days old) at three ages was subjected to high-throughput sequencing to predict testicular growth and development associated with WNT lncRNA. The final screening of lncWNT3-IT may be targeted to regulate the expression of WNT3. At the same time, the expression of WNT3 was verified by lncWNT3-IT by paraffin sectioning, fluorescence in situ hybridization, interference, overexpression, cytotoxicity assay, Western blotting and qPCR. The following results were obtained: lncWNT3-IT was expressed in the testicular Sertoli cells and played a role in the Sertoli cell cytoplasm. Fluorescence in situ hybridization localization analysis showed that lncWNT3-IT positively regulated the expression of WNT3, and through cell viability and cell proliferation experiments, it was found that the expression of lncWNT3-IT assisted in Sertoli cell proliferation. In summary, lncWNT3-IT can influence the proliferation of Sertoli cells by positively regulating the expression of WNT3.     

布奶杂交一代山羊生长发育及产肉性能试验研究

选择同期出生的布奶一代和当地奶山羊公羔各３０只，分两组观测生长发育情况；周岁时每组随机选取６只进行屠宰，测定产肉性能。结果表明：布奶一代具有极显著的杂种优势，周岁时体重达到４６．５ｋｇ，比奶山羊高１１．２５ｋｇ，平均产净肉１８．４３ｋｇ，比奶山羊多５．９１ｋｇ。     

波尔山羊与师宗山羊杂交效果试验研究报告

同时设置3个重复的杂交试验,在3群师宗母山羊中同时放入波尔及师宗种公羊各1只,自由交配观察测定种公羊的配种能力、产羔数、后代毛色、初生重、各月龄体重;并通过补饲对比试验测定波×师F1代的育肥性能和肉品品质。结果表明,波尔山羊的配种能力强,多羔率为48.72%,后代毛色近似父本的比例为64.91%;杂交羊适应性强,初生重提高18.27%;1～11月龄日增重提高17.79%;在其它条件相同的情况下,放牧加补饲的波×师F1代比单纯放牧的波×师F1代日增重提高85.16%,相同补饲条件下的波×师F1代比师×师日增重提高32.43%;每多增重1kg耗料量降低13.15%,耗料费降低13.03%。波×师F1代11月龄胴体重为(19.07±2.80)kg,净肉重为(15.47±2.20)kg,分别比同龄师×师羊(12.23±1.22)kg、(9.80±1.49)kg高55.93%、57.86%;品味鉴定、肉品理化特性和营养成分分析,其多汁性、嫩度、香气、香味、膻味、pH值、大理石纹、系水率、熟肉率、剪切力无明显差异。     

布尔山羊与福清山羊杂交效果初报

引入布尔山羊与福清山羊杂交 ,对布尔山羊、布福F1 羊和福清山羊适应性、生长发育性能进行研究。结果表明 :布尔山羊初生重、8月龄体重分别为 2 975、2 7 93kg ,与布福F1 羊、福清羊相比差异均极显著 (P <0 0 1)。布福F1 羊初生重、8月龄体重分别为 1 83、17 6 2kg ,与福清山羊相比 ,分别提高 15 0 9%和 41 81%,前者差异不显著 (P >0 0 5 ) ,后者差异显著(P <0 0 5 )。布福F1 羊的体表毛色与布尔山羊相似 ,而体尺与福清山羊相近。布福F1 羊的抗病力强于福清山羊 ,而弱于布尔山羊 ,适应性与后两者无明显差异。     

Profiling of miRNAs in porcine Sertoli cells

Background: Sertoli cells(SCs) create a specialized environment to support and dictate spermatogenesis.MicroRNAs(miRNAs), a kind of ~ 22 nt small noncoding RNAs, have been reported to be highly abundant in mouse SCs and play critical roles in spermatogenesis. However, the miRNAs of porcine SCs remain largely unknown.Methods: We isolated porcine SCs and conducted small RNA sequencing. By comparing miRNAs in germ cells, we systematically analyzed the miRNA expression pattern of porcine SCs. We screened the highly enriched SC miRNAs and predicted their functions by Gene Ontology analysis. The dual luciferase assay was used to elucidate the regulation of tumor necrosis factor receptor(TNFR)-associated factor 3(TRAF3) by ssc-miR-149.Results: The analysis showed that 18 miRNAs were highly expressed in SCs and 15 miRNAs were highly expressed in germ cells. These miRNAs were predicted to mediate SC and germ cell functions. In addition, ssc-miR-149 played critical roles in SCs by targeting TRAF3.Conclusion: Our findings provide novel insights into the miRNA expression pattern and their regulatory roles of porcine SCs.     

Prenatal and postnatal development of Sertoli cells in rams

The morphological picture of Sertoli cells was studied in view of development. The testicular tissue of rams was studied from the 80th to the 140th day of intrauterine development and the testes of ram-lambs were studied from the 1st to the 40th day from birth; further, the testes were studied in adult rams. The development and differentiation of Sertoli cell precursors were examined, including their change into differentiated mature Sertoli cells. The electron-microscopic picture of these cells was described with special emphasis on those morphological changes in cells which are closely related with their functional activity during the development of the testes. The findings obtained so far in this field are incomplete and concern mainly laboratory animals and man. The results of the study extend the theoretical knowledge in the fields of histology, embryology, physiology, endocrinology and andrology. At the same time, they may serve as starting material for the study of the control of spermatogenesis under experimental conditions.     

Immunolocalization of inhibin/activin subunits in the shiba goat fetal, neonatal, and adult testes

The objective of this study was to investigate the cellular immunolocalization of inhibin alpha and inhibin/activin (betaA and betaB) subunits in the fetal, neonatal and adult testes of Shiba goats. The testes were obtained from a fetus at 90 days, a neonate at 15 days, and two adult Shiba goats (both of 3 years old). The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA, and inhibin/activin betaB. Inhibin alpha and inhibin/activin (betaA and betaB) subunits were expressed in Leydig cells, but not in the Sertoli cells of the fetus with a weak immunostaining. An increase in the number of positive cells and a more intense immunohistochemical signal for inhibin alpha and inhibin/activin (betaA and betaB) subunits were observed in the Leydig cells of neonatal testes. Moreover, inhibin alpha, betaA, and betaB subunits were expressed in the Sertoli cells and Leydig cells of adult testes, respectively. These results suggest that Shiba goats testes have the ability to synthesize inhibins in the fetus, neonate, and adult, and the cellular localization of inhibin/activin subunits showed age-related changes in fetal, neonatal, and adult testes of Shiba goats.     

Development of goat embryos reconstituted with somatic cells: the effect of cell-cycle coordination between transferred nucleus and recipient oocytes

The developmental ability and the nucleus and microtubule dynamics of nuclear transplanted goat embryos derived from in vitro matured oocytes were studied while controlling cell-cycle coordination of donor embryonic nuclei and recipient cytoplasts. Three groups of transfers were studied: G0/G1 (after the fibroblast cells grew to 100% confluence) and G2/M (nocodazole treated) phase fibroblasts transferred to MII cytoplasts (G0/G1-->MII and G2/M-->MII group, respectively), and G0/G1 phase fibroblasts transferred to preactivated cytoplasts, mostly at S-phase, (G0/G1-->Pre group) by electrical fusion. The results showed that fusion and developmental ability did not differ between G0/G1-->MII and G0/G1-->Pre groups. However the developmental rate of embryos in the G0/G1-->MII group was significantly higher than that of the G2/M-->MII group. Most fibroblast nuclei (G0/G1 and G2/M) transferred into MII oocytes underwent premature chromosome condensation (PCC). Normal spindle were only detected in the G0/G1-->MII group. In contract, fibroblast nuclei in pre-activated oocytes rarely underwent PCC, but formed a swollen nuclear structure. The data suggest that in vitro matured goat oocytes can support the development of somatic fibroblasts after nuclear transfer, G0/G1 -->MII and G0/G1-->S nuclear transfer might be effective ways for improving the developmental competence of the reconstituted embryos, and that G2/M-->MII nuclear transfer by electrical fusion (even in Ca2+-free fusion medium) induces abnormal chromosome ploidy.     

Transplantation of bovine germinal cells into mouse testes

To develop techniques for spermatogonial transplantation in bulls, it is essential to have an effective bioassay procedure to evaluate the transplantation efficiency of spermatogonial stem cell collection, purification, and culture techniques. The objective of the present study was to develop a mouse bioassay model to evaluate transplantation efficiency of fresh and cultured bovine germ cells. Bull calves of four ages (1, 2, 3, and 4 mo) were used as a source of donor testes cells. Two calves were used for each age point, one calf was experimentally made cryptorchidistic at 1 wk of age and the other left normal. A STO (mouse fibroblast) feeder cell line was used to culture bovine testes cells for 2 wk preceding transfer into recipient testes. Immunodeficient nude mice (nu/nu) in which endogenous spermatogenesis had been abolished by busulfan treatment served as recipient animals for transplantation. Donor bovine germ cells were microinjected into mouse seminiferous tubules. Mouse testes were analyzed 2 wk after transplant with the use of a bovine-specific antibody and whole-mount immunohistochemistry for the presence of bovine donor germ cells. Bovine testis cells were present in all recipient mouse testes analyzed. Fresh bovine testes cells were observed as colonies of round cells within mouse seminiferous tubules, indicating spermatogonial expansion and colonization; however, cultured bovine testes cells appeared as fibrous tissue and not as spermatogenic colonies. The average number of colonies resulting from donor cryptorchid testes was not different (P > 0.05) from noncryptorchid, 56+/-4 and 78+/-7, respectively. Fresh donor cells from calves older than 1 mo gave rise to a greater average number of colonies within recipient testes (P <0.05) (1 mo, 33+/-4; 2 mo, 70+/-8; 3 mo, 63+/-6; 4 mo, 87+/-9). Fresh bovine germ cells are capable of colonization in the busulfan-treated nude mouse testis, making it a suitable model for evaluation and development of spermatogonial transplant techniques in bulls.     

山羊乳腺上皮细胞的生长特性

用组织块培养法获得山羊乳腺细胞原代培养物。根据山羊乳腺成纤维细胞与上皮细胞对胰蛋白酶的敏感性不同将二者分离纯化，对细胞生长特性进行了光镜观察。结果如下：细胞可形成闭合型细胞群和开放型细胞群。乳腺上皮细胞与成纤维细胞混生时，细胞之间形成许多腔状结构。纯化的乳腺上皮细胞通过单细胞悬浮后传代，部分细胞形成岛屿状聚集，部分细胞以贴壁的自由单个细胞散在形式存在。上皮细胞增殖可形成圆顶型结构，呈乳头状，称之为乳球体；可产生乳腺上皮细胞并分泌乳汁。山羊乳腺上皮细胞含不同的细胞类型．大多数上皮细胞呈短梭形或多角形。细胞之间紧密相靠。互相衔接。连接成片，呈蜂窝状；细胞核呈圆形或椭圆形．核仁2～4枚；部分细胞呈圆饼状，体积较大；出现部分长形细胞；接触抑制的上皮细胞形态不均一。纯化的山羊乳腺上皮细胞传代至第15代时其生长仍正常，经透射电镜观察发现细胞表面微绒毛极为发达，细胞质中线粒体和粗面内质网丰富，细胞质内有大量脂滴及小泡，表明第15代山羊乳腺上皮细胞增殖活力旺盛。染色体数目分析表明．该细胞系稳定，在离体培养条件下细胞不发生转化。山羊乳腺上皮细胞系的细胞染色体数目为60．染色体组型为2n=60。     

支持细胞骨架与精子发生研究进展

精子发生过程是支持细胞参与调控的一个精密的过程,支持细胞结构的完整性保证了精子发生的正常进行.支持细胞骨架包括微丝、微管和中间纤维,它们参与构成血睾屏障,为精子发生提供了物理支撑和稳定的微环境,对于维持生精上皮的完整性至关重要,影响支持细胞蛋白质的分泌,使分泌物定向转运.支持细胞骨架的损坏引起生殖细胞的凋亡和精细胞的变形及迁移异常.文章主要围绕影响精子发生的诸多因素对支持细胞骨架的作用及机制加以阐述.     

黔北麻羊与南江黄羊杂交后代屠宰及肉质性能比较

为进一步探究黔北麻羊杂交改良效果,选取相同饲养条件下同龄的纯种黔北麻羊和南江黄羊(♂)与黔北麻羊(♀)杂交后代南黔F1为试验组合,分别对其屠宰性能、肉质性能、不同组织肌肉纤维、肌肉中氨基酸和脂肪酸组成等方面进行对比分析。结果表明,黔北麻羊与南黔F1母羊在宰前活重、净肉重和胴体重指标差异极显著(P0.01),在眼肌面积和屠宰率指标差异显著(P0.05);黔北麻羊与南黔F1公羊净肉率指标差异极显著(P0.01),胴体重和屠宰率指标差异显著(P0.05);南黔F1在熟肉率、滴水损失、粗蛋白、粗灰分等指标均优于黔北麻羊。另外,南黔F1肉的总氨基酸(TAA)、必需氨基酸(EAA)、鲜味氨基酸(DTAA)和甜味氨基酸(STAA)含量略低于黔北麻羊肉,但EAA/TAA、EAA/非必需氨基酸(NEAA)、DTAA/TAA以及STAA/TAA含量十分接近;南黔F1较黔北麻羊饱和脂肪酸相对含量仅差0.05百分点,不饱和脂肪酸相对含量较黔北麻羊高出0.06百分点。南黔F1羊的屠宰性能显著高于黔北麻羊(P0.05),南黔F1肉品品质优于黔北麻羊,说明南江黄羊杂交改良后的黔北麻羊屠宰性能和肉品质均得到了提高。     

Pathophysiology of small testes in beef bulls: relationship between scrotal circumference, histopathologic features of testes and epididymides, seminal characteristics, and endocrine profiles

Tissue sections from testes and epididymides obtained from 17 young beef bulls with scrotal circumference (SC) between 27 and 40.5 cm were studied to determine whether small testes were a manifestation of lesions or a result of less, but otherwise normal, seminiferous epithelium. The SC correlated negatively with the estimates of germinal epithelial loss and positively with seminiferous epithelial area. Four bulls with SC less than 30 cm had severe lesions in their testes. Hypoplastic tubules were characterized by Sertoli's cells only with no evidence of germinal cells. Loss of germinal cells, leaving vacuolated epithelium and atrophy, were observed in degenerated tubules. Hyperplasia of Leydig's cells was observed in the vicinity of Sertoli's cell-only tubules, resulting either from degeneration or hypoplasia, and atrophy of Leydig's cells was associated with tubules devoid of Sertoli's cells. These findings indicated that Sertoli's cells may produce a factor(s) required for maintenance and regulation of Leydig's cell function. Epididymal epithelium, especially in the head, had regressed in bulls with hypoplastic and degenerative changes in their testes. Decreased sperm concentration and motility and an increased frequency of morphologic defects were observed in the 4 bulls with testicular lesions and regressed epididymal epithelium. Blood plasma profiles of cortisol, follicle-stimulating hormone, luteinizing hormone, and testosterone were determined in the 4 bulls with SC less than 30 cm and 10 of the 13 bulls with SC greater than 30 cm. There were no statistically significant (P greater than 0.1) differences in the responses to exogenous gonadotropin-releasing hormone or base-line patterns of blood plasma follicle-stimulating hormone and luteinizing hormone between the 2 groups. However, in the bulls with SC less than 30 cm, the mean concentration of testosterone was lower, whether spontaneous (P less than 0.05) or exogenous gonadotropin-releasing hormone induced (P less than 0.1). The fact that these bulls were not deficient in gonadotropins indicated that Leydig's cell function was impaired by local factors, either the factors that caused the tubular damage or those consequent to the tubular damage.     

Myogenic and adipogenic properties of goat skeletal muscle stem cells

The aims of the present study were to establish a culture system for goat skeletal muscle stem cells and to examine their myogenic and adipogenic properties in vitro. Cells were isolated from the skeletal muscle of the Shiba goat and cultured in vitro. Most of the cells were positive for myogenic markers, such as Pax7, MyoD, and desmin, and immunocytochemistry revealed they differentiated to form myotubes expressing myosin heavy chain, indicating they were highly myogenic. Myogenic differentiation was strongly suppressed by the addition of basic fibroblast growth factor, while proliferation was unaffected. When the cells were cultured in adipogenic differentiation medium, some of the cells differentiated into mature adipocytes that stained with Oil Red-O. These cells were immunocytochemically positive for adipogenic markers, including peroxisome proliferator-activated receptor-gamma (PPAR gamma) and CCAAT/enhancer-binding protein-alpha (C/EBP alpha). These results clearly demonstrate the presence of both myogenic and adipogenic stem cells in goat skeletal muscle.     

波尔山羊杂交改良萨能山羊和本地山羊试验报告

用波尔山羊冷冻精液与萨能山羊、浦江本地山羊杂交，杂一代羊体尺、体重有较大幅度提高。波萨山羊比萨能山羊6月龄体高、体长、胸围分别提高8．05％、7．95％、8．24％，初生重、6月龄重分别提高12．08％、20．53％，差异显著。波本山羊比本地山羊6月龄体高、体长、胸围分别提高22．85％、22、75％、18．42％，初生重、6月龄重分别提高41．53％、79．43％．差异极显著。每只波萨山羊比萨能山羊增加收入41．30元。每只波本山羊比本地山羊增加收入95．40元。