Reproduction in Sminthopsis-Macroura (Marsupialia, Dasyuridae) .2. The Male

1990 ◽  
Vol 38 (2) ◽  
pp. 207 ◽  
Author(s):  
PA Woolley
Keyword(s):  
Breeding Season ◽  
Sexual Maturity ◽  
Binding Capacity ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Histological Changes ◽  
Accessory Glands ◽  
Sminthopsis Macroura ◽  
Sexually Mature ◽  
Androgen Levels

The breeding season of S. macroura extends from June to February, and individual males (both wild- caught and laboratory-reared) are capable of breeding over extended periods during the breeding season, and for up to three seasons, in the laboratory. Gross and histological changes in the reproductive organs and endocrine changes in relation to reproductive activity have been investigated. Males do not appear to reach sexual maturity until the season following that in which they were born, although spermatorrhoea may commence in the season of birth. Testis and epididymis weight of these males, which commence spermatorrhoea late in the season, approximates that of sexually mature males early in the season but androgen levels and the weight of the accessory glands are low in all males except during the early months of the season. The age at which spermatorrhoea commences ranges from 141 to 350 days. The minimum scrota1 width at which it commences is 7.9 mm and the minimum body weight, 14.0 g. The onset of spermatorrhoea is not a function of age or season and in S. macroura should be used with caution as an indicator of impending sexual maturity. Maximum corticosteroid- binding capacity (MCBC) generally exceeded corticosteroid concentration and no androgen-related fall in MCBC was evident.

Studies on the marsupial glider, Schoinobates volans (Kerr) I. Reproduction

1969 ◽  
Vol 17 (4) ◽  
pp. 625 ◽  
Author(s):  
RFC Smith
Keyword(s):  
Natural Population ◽  
Breeding Season ◽  
Reproductive Cycle ◽  
Reproductive System ◽  
Sexual Maturity ◽  
Field Data ◽  
Reproductive Organs ◽  
Female Reproductive System ◽  
Histological Changes ◽  
Second Year

Field data were obtained during the period September 1962-January 1965 from 710 greater gliders, S. volans, in a natural population. Histological changes were observed in the reproductive tracts of another 129 animals shot during this period. S. volans has a short breeding season in March, April, and May, after which involution of the reproductive organs occurs in both sexes. The species is monovular and polyoestrous. Sexual maturity is attained by both sexes in the second year, following which breeding probably occurs annually. The female reproductive system shows several primitive and anomalous features, among which is the retention of the Wolffian ducts in the adult. The histology of ovaries, uteri, and vaginae at various stages of the reproductive cycle is briefly described.

scholarly journals Histological Development of Male Reproductive Organs in Microminipigs

2016 ◽  
Vol 44 (8) ◽  
pp. 1105-1122 ◽  
Author(s):  
Akihisa Kangawa ◽  
Masayoshi Otake ◽  
Satoko Enya ◽  
Toshinori Yoshida ◽  
Masatoshi Shibata
Keyword(s):  
Giant Cell ◽  
Sexual Maturity ◽  
Multinucleated Giant Cell ◽  
Reproductive Organs ◽  
Tubular Structure ◽  
Structural Development ◽  
Tubular Atrophy ◽  
Accessory Glands ◽  
Male Reproductive Organs ◽  
Sexually Mature

Microminipigs are becoming increasingly attractive alternatives for various experimental applications, such as general toxicology studies, owing to their manageable size. However, there are limited studies on the male reproductive organs of microminipigs, particularly on the histological aspects of sexual maturity. To clarify the development of male reproductive organs, 35 male microminipigs, aged 0 to 12 months, were used in this study. Histological and histomorphological evaluation was performed based on spermatogenic development, measurement of tubular structure in testes and epididymides, and histological progress of accessory glands. In addition, spontaneous testicular changes were quantitatively assessed. Histologically, male microminipigs sexually matured around 4.5 months of age, when spermatogenesis in testes and structural development in genital organs were completed. Spontaneous testicular changes occurred in all the animals investigated. Multinucleated giant cell was most commonly observed, followed by hypospermatogenesis and tubular atrophy/hypoplasia. However, the number of affected tubules was less than 1% in testes after 4.5 months of age, suggesting that the influence of these changes on evaluation of toxicity studies may be minimal. It is preferable to use sexually mature animals in toxicology studies; therefore, the information obtained by the present study will be helpful for future toxicity evaluations in microminipigs.

scholarly journals Chromosome behaviour in the male ferret and mole during anoestrus

1936 ◽  
Vol 121 (822) ◽  
pp. 192-206 ◽  
Keyword(s):  
Seasonal Variation ◽  
Breeding Season ◽  
Reproductive Organs ◽  
Quiescent State ◽  
Chromosome Behaviour ◽  
Histological Changes ◽  
Short Period ◽  
Cytological Changes

The breeding season of many Mammals is restricted to a relatively short period of the year. In such species usually both sexes exhibit a more or less well-defined seasonal variation in their reproductive organs. Several investigators have found that these variations in the male consist chiefly of alteration in the size of the testes and epididymis, accompanied by marked histological and cytological changes leading to a complete absence of sperms during the quiescent or anoestrous period. The cyclic histological changes in the testes and in the accessory organs have been described in detail in the ferret ( Putorius furo, L .) by Allanson (1932), and in the mole ( Talpa europea, L .) by Tandler and Grosz (1912) and Allanson ( unpublished ). It was found in both genera that during the breeding season spermatogenesis is complete and very active in the rapidly growing testis, but after that period the reproductive organs return to a quiescent state and sperms are entirely absent.

scholarly journals On the relation between the anterior pituitary body and the gonads.- Part II. The induction of ovulation in the anæstrous ferret

1930 ◽  
Vol 107 (748) ◽  
pp. 39-49 ◽  
Keyword(s):  
Recent Work ◽  
Breeding Season ◽  
Anterior Pituitary ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Oestrous Cycle ◽  
Induction Of Ovulation ◽  
The Common ◽  
Reproductive Processes ◽  
Increased Activity

The factors responsible for the alternation of reproductive activity and anæstrous quiesecence are imperfectly known, but in view of much recent work on the regulation of the ovary (Smith and Engle, 1927, Zondek and aschheim, 1927), it is necessary to suppose that the anterior pituitary body is involved. On such a view anæstrus might be caused by inability of the ovary to respond to stimulation from the hypophysis, but it is more reasonable to suppose that the onset of the breeding season is due to increased activity of the anterior pituiary body, and that anæstrus results from decreased activity. In the circumstances it seemed that results of interest might be obtained by the administration of preparations containing the gonad-stimulating principles of the anterior pituitary body to animals during anæstrus. Most of the common labortory animals have no definite anæstrus, and the choice of an animal for work on anæstrus is almost limited to the ferret ot the dog. Of these, the former is obviously more suitable, especially as a considerable amount id now known about its reproductive processes. The work of Marshall (1904), Robinson (1918) and Marshall and Hammond (1930) has made it possible to make the following statements regarding the œstrous cycle in the ferret:- ( a ) The breeding season in restricted and lasts only from April to August. During the remainder of the are the reproductive organs are in a state of quiescent anæstrus.

scholarly journals B-mode and Doppler Ultrasonography of Accessory Genital Glands and Testes in Male Goats During the Breeding Season

2021 ◽  
Vol 53 (2) ◽  
Author(s):  
Hamed Talaat Elbaz ◽  
Ahmed Mohamed Sharshar ◽  
Ahmed Essam Elweza
Keyword(s):  
Breeding Season ◽  
Pulsatility Index ◽  
Doppler Ultrasonography ◽  
Resistive Index ◽  
Serum Testosterone ◽  
Reproductive Organs ◽  
Accessory Sex Glands ◽  
Spectral Doppler ◽  
Doppler Indices ◽  
Sexually Mature

The aims of the present study were to scan the echogenicity of reproductive organs of bucks during the breeding season. The influence of testosterone on haemodynamic Doppler indices of accessory genital glands of breeding bucks was also examined. Ten clinically healthy, sexually mature, Egyptian Baladi male goats were examined and the testes, tail of epididymis and accessory sex glands imaged using greyscale B-mode, colour Doppler ultrasonography. The spectral Doppler indices (pulsatility index and resistive index) were measured. Blood samples were collected and serum concentrations of testosterone, FSH and LH were determined. The results revealed that the echogenicity of testes, tail of epididymis and accessory genital glands was changed by breeding season. Pulsatility index values of supra-testicular artery, marginal artery, tail of the epididymis, ampulla, vesicular gland, pars disseminata of the prostate and bulbourethral gland were 0.85±0.04, 0.54±0.03, 0.4±0.03, 0.37±0.04, 0.51±0.03, 0.39±0.02 and 0.41±0.04, respectively. The resistive index of the above criteria were 0.51±0.04, 0.37±0.02, 0.3±0.03, 0.27±0.02, 0.31±0.03, 0.32±0.03 and 0.32±0.03, respectively. Serum testosterone concentration was 4.78±0.46 ng/mL. Furthermore, FSH and LH were 3.71±0.43 and 1.8±0.17 mIU/mL, respectively. Interestingly, testosterone clearly deceased the values of the both the pulsatility and resistive indices of the accessory genital glands of breeding bucks. Season modified the echogenicity of testes, epididymis and accessory genital glands. Testosterone regulated the reproductive indices of blood flow of the accessory genital glands of breeding bucks. Thus, this study could serve as a baseline of reference values of Egyptian Baladi male goats during the breeding season to improve reproductive efficiency.

Structure, histochemistry, ultrastructure and seasonal variations of the male prostatic complex in the black Myotis bat, Myotis nigricans (Chiroptera: Vespertilionidae)

2014 ◽  
Vol 26 (8) ◽  
pp. 1188 ◽  
Author(s):  
Ana C. Negrin ◽  
Mateus R. Beguelini ◽  
Cintia C. I. Puga ◽  
Caroline M. Christante ◽  
Larissa M. Bueno ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Reproductive Strategies ◽  
Reproductive Organs ◽  
Seminal Vesicles ◽  
Considerable Variability ◽  
Annual Reproductive Cycle ◽  
Paulo State ◽  
Accessory Glands ◽  
Wide Geographic Distribution ◽  
Sexually Mature

Chiroptera are one of the most diverse orders of mammals and a unique group within Mammalia that posses a wide geographic distribution and considerable variability in reproductive strategies. The aims of the present study were to characterise the male prostatic complex of the bat Myotis nigricans (Vespertilionidae) and evaluate seasonal variations in the prostatic complex of M. nigricans specifically. Twenty-three sexually mature specimens (four sample groups: winter, spring, summer and autumn) were subjected to macroscopic, microscopic, morphometric and ultrastructural analyses. The reproductive accessory glands of M. nigricans were found to be composed of a multilobed complex associated with the urethra and a pair of inguinal bulbourethral glands. The complex was composed of three bilobed prostatic regions (ventral, dorsolateral and dorsal) with no ampullary gland and seminal vesicles. This pattern of lobulation is very similar to that described for the prostate of rodents; however, it differs from that of other mammals and even other families of bats (e.g. Phyllostomidae and Molossidae). Each prostatic region in M. nigricans has unique and distinctive characteristics, which synchronise to establish the main reproductive peak of the species in summer. The data also indicated an asynchrony in the activity of primary and secondary reproductive organs in the annual reproductive cycle of M. nigricans in São Paulo State, Brazil.

scholarly journals The reproductive processes of certain mammals. III.—The reproductive cycle of the male ferret

1932 ◽  
Vol 110 (767) ◽  
pp. 295-312 ◽  
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Reproductive Tract ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Interstitial Tissue ◽  
Quiescent Period ◽  
Cyclic Changes ◽  
Reproductive Processes ◽  
Periodic Changes

Cyclic changes in the reproductive organs of male mammals have been studied in a few forms only, but the information available reveals interesting differences in the duration of reproductive activity, and in the correlation between the various organs. Marshall (1911) has described the reproductive cycle in the male hedgehog. Regaud (1904), Tandler and Grosz (1911) and Lecaillon (1909) have studied the mole, but with conflicting results. Rasmussen (1917 and 1918) gives detailed information of the periodic changes in the interstitial tissue of the testis in the woodchuck, and more recently Courrier (1923) has investigated the reproductive cycle in various bats, in the mole, hedgehog, and marmot. The work of Marshall (1904), Robinson (1918) and Hammond and Marshall (1930) has established that in the female ferret the breeding season is restricted and lasts from April to August ; during the remaining months of the year the reproductive organs are in a state of quiescent anœstrus. The first mating occurs in March or April. The present investigation was undertaken in order to determine the duration of the quiescent period in the male ferret and to compare the changes in the testis tubules with those in the interstitial tissue and accessory organs. The condition of the reproductive tract has accordingly been studied at various times of the year, and an attempt has been made to assess the changes in the organs and in their constituent parts.

scholarly journals VII. The Reproductive processes of certain mammals. Part VII. - Seasonal variation in the reproductive organs of the male hedgehog

1934 ◽  
Vol 223 (494-508) ◽  
pp. 277-303 ◽  
Keyword(s):  
Reproductive Cycle ◽  
Experimental Work ◽  
Genital Tract ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
General Nature ◽  
Secretory Cycle ◽  
Accessory Glands ◽  
Wide Range ◽  
Cyclic Changes

The seasonal changes in the genital tract of the male hedgehog, notably the enormous hypertrophy of the accessory sexual glands in the spring and summer, early attracted the attention of biologists. The first important account of the reproductive cycle was given by Marshall (1911) who described the histological condition of the testis at different seasons and found that the production of spermatozoa commenced as early as January and continued to the end of September. The summer and winter appearance of the prostate and Cowper’s glands was described by Griffiths (1890), and in 1926 Pellegrini published observations on the secretory cycle in the interstitial cells of the testis. Courrier (1927) studied the cyclic changes in the various organs and gave a full bibliography of work on the male hedgehog. Animals with restricted reproductive activity have already proved valuable for experimental research (Hill and Parkes, 1932 ; Bissonnette, 1932), and earlier workers recognized the suitability of the hedgehog in this connection. Marshall (1911), by castrating hedgehogs at various phases of the reproductive cycle, showed that the periodic hypertrophy and continued activity of the accessory glands was controlled by the testes, and Courrier extended and confirmed his findings. The hedgehog should prove useful in a wide range of experimental work, for, besides possessing remarkable accessory glands, it is probably the only mammal with abdominal testes that can be easily obtained in England and kept in captivity. Although the general nature of the reproductive cycle has been described, previous authors have been content to examine a few animals only, and it was therefore thought desirable to examine a series sufficiently large to provide an adequate quantitative basis for experimental work. In addition, the large number of immature animals obtained supplied information on the rate of development of the genital tract before the first breeding season.

Reproduction in Wild Canids, Canis-Familiaris, From the Eastern Highlands of Victoria

1988 ◽  
Vol 15 (4) ◽  
pp. 385 ◽  
Author(s):  
E Jones ◽  
PL Stevens
Keyword(s):  
Breeding Season ◽  
Sexual Maturity ◽  
Canis Familiaris ◽  
Seminiferous Tubules ◽  
Seasonal Breeding ◽  
Peak Period ◽  
Wild Canids ◽  
Initial Onset ◽  
Eastern Highlands ◽  
Sexually Mature

Reproduction was studied in a group of wild canids collected over four years from the eastern highlands of Victoria. While births were recorded from March to September inclusive, 78% of them took place in the winter months of June-August, with the peak occurring in July. A single breeding season each year was indicated for most, with a mean prenatal litter size of 5.5 (range 2-9). Sexually mature males were fertile throughout the year, although they exhibited a significant increase in testes weight, epididymides weight, and number of active seminiferous tubules for the months of April-June, which corresponded to the peak period of oestrus in females. The onset of first oestrus in females was variable, occurring when they were 1-4 years old, with only 36% of those less than 2 years old sexually mature. Sexual maturity in males was also variable. For animals of 10 kg (weight at initial onset of spermatogenesis) or heavier, spermatogenesis had commenced in only 63% of those less than two years old, but increased to 97% of those more than three years old. Overall this sample of canids displayed reproductive characteristics, such as a seasonal breeding season, considered typical of dingoes. However the possibility of slight changes to the original dingo breeding patterns through hybridization with domestic dogs is discussed.

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