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1.
To determine the full potential of the compost worm Eisenia fetida as waste processor and as source of protein, the life-cycle of this species had to be studied thoroughly. The development, growth and reproduction of Eisenia fetida were studied on cattle manure under favourable conditions of moisture, temperature and nutrition. Data were gathered over a period of 600 days. Apart from the life-cycle this study also indicated that this species can be reproductively active for more than 500 days. This is significantly longer than had previously been believed. Each cocoon produced a mean of 2,7 hatchlings after a mean incubation period of 23 days. These worms attained sexual maturity after 40 to 60 days and produced their first cocoons within four days after mating took place.  相似文献   

2.
The literature available on the agouti (Dasyprocta leporina) is very limited. The agouti is a Neotropical rodent found in Trinidad and Tobago, Central and South America. This study focuses on one of the many unexplored areas relating to the species, the male reproductive system. The results showed that the mean testicular length, diameter and weight was 3.67 +/- 0.12 cm, 1.67 +/- 0.04 cm and 5.03 +/- 0.52 g respectively. The paired testes and epididymis were found in contact with the abdominal muscles within scrotal pouches, which are evaginations of the caudoventral abdominal wall. The caput epididymis is enclosed by a fat body. The ductus deferens has a mean length and diameter of 10.98 +/- 0.40 cm and 0.14 +/- 0.01 cm respectively. At the urethral end of the ductus deferens the diameter of each duct expends to form the ampulla. The mean diameter of each of the ampulla was 0.25 cm. The accessory sex organs of the male agouti (D. leporina) include the vesicular glands, the coagulating glands, the prostate glands and the bulbourethral glands. The penis of the agouti is U-shaped with a mean length of 9.90 +/- 0.43 cm. The glans penis contains an os penis, a pair of lateral penile cartilages and paired ventral keratinaceous styles.  相似文献   

3.
Zhedong white goose (Anser cygnoides domesticus) is a native Chinese breed with strong broodiness and low egg production, which is related to the physiology of reproduction. However, thus far, the physiology of goose reproduction has not been well elucidated. In the present study, the ovarian morphology and reproductive hormones of Zhedong white geese were investigated during the reproductive cycle (the laying and brooding periods). The results showed that the surface of the ovary was atrophied and follicular atresia appeared to some extent in the brooding period compared with the laying period. The concentrations of follicle-stimulating hormone, progesterone and luteinizing hormone were significantly higher than those in the brooding period (p < 0.05). In contrast, the concentrations of prolactin (PRL) and anti-Müllerian hormone (AMH) in the laying period were significantly lower than those in the brooding period (p < 0.05). In addition, the mRNA expression levels of PRL, AMH, dopamine-β-hydroxylase (DβH) and cytochrome P450 side-chain cleavage enzyme (P450scc) were detected in the hypothalamus, pituitary and ovaries by using real-time polymerase chain reaction. The results showed that AMH mRNA was expressed specifically in ovary tissue. The expression levels of DβH and PRL in the brooding period was significantly higher than those in the laying period in the three tissues, especially in the early and middle stages of the brooding period. Moreover, AMH mRNA expression in the ovaries presented the same trend. In addition, P450scc mRNA was highly expressed in both the ovary and pituitary in the laying period. These results revealed the remarkable features of ovarian morphology and characterized the hormonal pattern and expression profile during the reproductive cycle, all of which contribute to understanding the differences in reproductive physiology between the laying and brooding periods in Zhedong white geese.  相似文献   

4.
Earthworms (Oligochaeta,Lumbricidae) and mycobacteria   总被引:4,自引:0,他引:4  
The objective of the study was to define the role of earthworms in the survival of mycobacteria in animal populations. In 13 sampling sites mycobacteria were detected in 53 (5.5%) samples of faeces and parenchymatous tissues from animals, in 25 (7.3%) environmental and in nine (8.2%) earthworm samples. In cattle and goat farms affected by Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) of IS900 restriction fragment length polymorphism (RFLP) type B-C1 was isolated from 37 (4.6%) faecal samples, three (1.4%) environmental and one (3.1%) earthworm sample. Investigations of aviaries affected by avian tuberculosis detected M. avium of genotype IS901+ and IS1245+ in six (7.9%) bird's faecal and in four (4.4%) environmental samples. M. avium (genotype IS901- and IS1245+) was detected in four (4.4%) and M. abscessus in one (1.1%) environmental sample. M. avium of genotype IS901- and IS1245+ and M. gastri were isolated from three (6.4%) earthworm samples. In pig farm with mycobacteriosis M. avium of genotype IS901- and IS1245+ was detected in five (20.0%) faecal samples from pigs and in four (12.9%) environmental samples. M. scrofulaceum was isolated in one (4.6%) sample of Lumbricus rubellus. In laboratory experiments identical RFLP types of M. paratuberculosis were isolated from bodies and faeces of earthworms 1-2 days after the last contact with the faeces contaminated with the same RFLP type of M. paratuberculosis. The results suggest that earthworms may become vectors of mycobacteria.  相似文献   

5.
对我国特有动物--高原鼠兔(OchotonaCurazoniae)在上海地区的若干繁殖特性作了观察.结果表明,鼠兔的精子畸形率较高(为11.64%),影响了其在上海低海拔地区的繁殖;非繁殖季节应用外源生殖激素对诱导雄性鼠兔的睾丸发育亦有一定的效果.  相似文献   

6.
1. The influence of age at thyroidectomy on reproductive activity of male turkeys was investigated. 2. Thyroidectomy of 53-week-old male domestic turkeys that had been reproductively active for 25 weeks resulted in undetectable plasma thyroxine concentrations, termination of semen production and testicular regression. Daily light-dark treatment was 14L:10D before and after thyroidectomy. 3. Thyroidectomy of 28-week-old, reproductively inactive, males maintained on a daily light-dark cycle of 8L:16D resulted in increased semen volumes following photostimulation with 14L:10D at 32 weeks of age. Semen quality was not affected, while plasma thyroid hormone concentrations were undetectable. The moult and termination of semen production that occurred in response to changing the daily light-dark cycle from 14L:10D to 8L:16D near the end of the study were inhibited by thyroidectomy. 4. The requirement for the thyroid glands in the reproductive processes of male turkeys changes either with age or after an extended period of reproductive activity.  相似文献   

7.
The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.  相似文献   

8.
An experimental investigation revealed that cocoon production by E. foetida (Oligochaeta) increased linearly with increase in temperature in the range 10 to 25 °C. Diurnally fluctuating temperature did not have a marked influence on total cocoon production at the temperature levels of 10, 15 and 25 °C. A highly significant difference in cocoon production occurred between a constant temperature of 20 °C and a mean temperature of 20 °C (which fluctuated diurnally between 12 and 28 °C). Maximum cocoon production was obtained at 25 °C with each worm producing a cocoon every second day. The investigation also showed that temperature does influence the number of hatchlings per cocoon. At a temperature of 25 °C fewer worms hatched per cocoon than at 20 °C.  相似文献   

9.
香猪睾丸发育的形态学变化   总被引:1,自引:0,他引:1  
为了解香猪睾丸发育过程中的形态学变化,外科手术取30、40、50、60、90、110日龄(每个年龄组n=3~4)香猪右侧睾丸经中性多聚甲醛固定,石蜡包埋,组织切片采用HE染色,40倍物镜下观察细胞数量变化,经显微照相后用Scion image软件测量生精小管、输出小管和附睾管的管壁面积。结果发现30~50日龄时睾丸生精...  相似文献   

10.
11.
Physical examination requires very little equipment or expense and is an effective means of obtaining valuable information concerning fertility. Thorough evaluation of the reproductive system provides important information often unattainable by any other means. Disease processes, congenital abnormalities, injuries, management errors, and many other factors can be identified. No segment of the examination should be overlooked, as each part is important. The time invested in evaluating the male reproductive system is rewarded with a more complete and accurate assessment of the breeding male.  相似文献   

12.
《畜牧与兽医》2017,(9):121-124
L-精氨酸是氮氧化物(NO)和多胺等生物活性物质合成的前体,具有改善繁殖能力、心血管功能、胃肠道发育及调控免疫功能等多种作用。本文就精氨酸对雄性繁殖能力的影响进行了论述,以期对雄性动物的养殖生产有一定的理论作用。  相似文献   

13.
The columella amis in Crocodilus niloticus has been found to comprise the two upper segments of the hyoid arch, viz., a forked pharyngohyal and an epihyal. To these two primary arch divisions becomes added a laterohyal component derived from delaminating subepidermal blasteme. The crocodilian stapes represents the infrapharyngohyal; the suprastapedial stem (or basal portion of the lacertilian dorsal process) represents the suprapharyngohyal while the extrastapedial represents essentially the epihyal to which laterohyal material contributes the tympanic process as well as the suprastapedial (or lacertilian intercalary). The lateral limb of the so-called lateral prong of the reptilian and avian columella auris is also a laterohyal derivative. It is concluded that in reptiles and birds: (a) the lateral limb and intercalary represent the dorsal articular head of the rhipidistian hyomandibula, (b) the proximal end of the epihyal represents its ventral articular head and (c) the so-called Huxley's foramen is the original passage between the two. Since the lacertilian internal process arises from the pharyngohyal it cannot represent the original rhipidistian quadrate-hyomandibular articulation.  相似文献   

14.
The morphology and morphogenesis of jaagsiekte retrovirus (JSRV)   总被引:1,自引:0,他引:1  
Jaagsiekte retrovirus ( JSRV ) was recently shown to be the aetiological agent of jaasiekte (ovine pulmonary adenomatosis). The morphogenesis of JSRV was studied in jaagsiekte tumour tissue. Intracytoplasmic particles, often associated with centrioles, were found in tumour cells. JSRV budded from tumour cells with a complete core which appeared to mature during the budding process. Extracellular particles were found in the alveolar lumen. Immature extracellular particles were rare. Mature extracellular JSRV was membrane-bound and had a slightly eccentric nucleoid with an electron-dense perinucleoidal space. In negatively stained preparations of JSRV the envelope was covered with spikes. JSRV is morphologically distinct from all known retroviruses.  相似文献   

15.
16.
The morphology and distribution of supraependymal structures in the ventricular system of sheep of both sexes were studied by common histological methods. Seven forms of supraependymal structures were distinguished according to shape; they are most frequent and most variable in the infundibular region of the third cerebral ventricle. In the ewes their occurrence in this region depends on the status of the ovarian cycle and in the rams it depends on the year season. The most frequent forms are hemi-spherical to spherical light-coloured protrusions and the so-called blebs: in the ewes they occur during anoestrus and, to a minor extent, during proestrus, and in rams in the "rest" period. In the winter reason (the rest period) the rams have button-like formations on ependyma surface in the infundibular region, and in summer there are finger-like protrusions. No such structures occur in the ewes. A larger part of the supraependymal structures are believed to be products of ependyma secretion which, in the infundibular region but nowhere else, is associated with sex: with the ovarian cycle in the ewes and with the year season in the rams.  相似文献   

17.
Lectins are glycoproteins of plant and animal origin that have the ability to bind specific carbohydrate residues of cell glycoconjugates, particularly in terminal positions. In this study, the binding of lectins, Dolichos biflorus agglutinin (DBA), soybean agglutinin (SBA), Bandeiraea simplicifolia BS-1 (isolectin B4), Triticum vulgaris (WGA), Arachis hypogaea (PNA), and Ulex europaeus (UEA-I), was studied in the reproductive systems of male thoroughbred horses.DBA was detected in the stereocilia of the caput and corpus epididymis, and in the vas deferens. It was weakly detected in connective tissue of the corpus epididymis. Strong SBA staining was seen in epithelial cells in the testis, stereocilia of the corpus and cauda epididymis, and in the vas deferens. There were intense positive reactions for isolectin B4 in interstitial cells in all tissue and serosa of the vas deferens. PNA staining was seen only in stereocilia in the caput and corpus epididymis, and in the vas deferens. Strong WGA staining was seen throughout the testis, except in Sertoli cells, stereocilia, and connective tissue. UEA-I was detected in secondary spermatids, stereocilia, and epithelial cells of the cauda epididymis. These results show that degenerating cells in the testis, epididymal tubules, and vas deferens have differential affinities for lectins, and suggest that lectins play a role in the reproductive system of the horse. The heterogeneity of the lectin staining pattern in the reproductive tubules of adult horses suggests that the carbohydrate composition of each cell type is region specific.  相似文献   

18.
The objective of this study was to determine the pathogenesis of experimental infection with a type 1 porcine reproductive and respiratory syndrome virus (PRRSV) by defining the sites of viral replication and apoptosis in male gonads from infected boars for a period of 21 days after intranasal inoculation. Microscopically, hypospermatogenesis and abundant germ cell depletion and death were observed in the testes. Such germ cell death occurs by apoptosis, as determined by a characteristic histological patterns and evidence of massive DNA fragment detected in situ terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) reaction. PRRSV was detected in the testicular tissue of infected boars only. Viral nucleic acid was localized in spermatogonia, spermatocytes and spermatids but not in the vesicular and bulbourethral gland. In serial sections, PRRSV-positive cells did not co-localized with apoptotic cells. TUNEL-positive apoptotic cells were more numerous than PRRSV-positive cells in testicular sections. The present study demonstrated that type 1 PRRSV infects the spermatogonia and their progeny, and induces apoptosis in these germ cells.  相似文献   

19.
Three male Beagle litter-mates, which were kept in the same environment and fed on the same diet, were studied from 20 to 45 weeks of age. The first ejaculates were obtained at 33 weeks in one and 34 weeks in two of the puppies. Ejaculatory volume, sperm concentration, libido increased quickly and although the early ejaculates contained large numbers of abnormal spermatozoa they soon decreased. By 45 weeks of age the seminal characteristics were comparable with those reported for adults. Plasma testosterone concentrations increased at the time that the first ejaculate was obtained.  相似文献   

20.
通过给不同月龄雄性W istar大鼠饮用添加1%牛磺酸或1%β-丙氨酸(牛磺酸转运抑制剂)的自来水,研究牛磺酸对不同月龄雄性大鼠体重、生殖器官指数及生殖激素分泌水平的影响。结果表明:牛磺酸对不同月龄大鼠体重、睾丸指数、前列腺指数没有明显的影响,但显著提高了14月龄大鼠的精囊腺指数;显著提高不同月龄雄性大鼠的血清睾酮水平(P<0.05),对血清促卵泡生成素(FSH)、促黄体生成素(LH)水平没有显著的影响。  相似文献   

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