Seasonal variation in the reproductive activity of the wild rabbit (Oryctolagus cuniculus algirus) in a Mediterranean ecosystem

2002 ◽  
Vol 29 (2) ◽  
pp. 165 ◽  
Author(s):  
H. Gonçalves ◽  
P. C. Alves ◽  
A. Rocha
Keyword(s):  
Oryctolagus Cuniculus ◽  
Seasonal Pattern ◽  
Reproductive Activity ◽  
Mediterranean Ecosystem ◽  
Seminiferous Tubules ◽  
Corpora Lutea ◽  
Clear Understanding ◽  
Wild Rabbit ◽  
Sperm Production ◽  
Daily Sperm Production

To establish a successful strategy for managing wild rabbit (Oryctolagus cuniculus algirus) populations it is essential to have a clear understanding of reproductive biology. In Portugal, previous work suggested a seasonal pattern of reproductive activity for this species. In this study we present additional information on the seasonal reproductive activity of the wild rabbit as well as data on the influence that environmental factors have on the onset and length of the breeding season. The study was carried out in Pancas, southern Portugal, from October 1997 to September 1998. Rabbits were collected every two months and post mortem analyses were performed. In the males, circulating concentration of testosterone, gonadal weight, daily sperm production, diameter of the seminiferous tubules and the thickness of epithelial cells were measured. The numbers of corpora lutea, embryos and placental scars were recorded in the females. To assess abundance and quality of food, samples of herbaceous vegetation were collected and analysed for water, fibre and crude protein content. The reproductive season extended from November to June with a peak in March/April, with both sexes showing an annual cycle of gonadal development and subsequent regression. All analysed females were pregnant and/or lactating between March and June. The mean litter size estimated by counting the embryos in the uteri was 3.90 ± 0.50. Daily sperm production was highest between November and April. Testicular function was strongly correlated with environmental temperature and the water content of the vegetation, and both testicular and ovarian development were correlated with vegetation biomass.

scholarly journals Determination of Daily Sperm Production (DSP) in Rabbit (Oryctolagus cuniculus) Bucks using Testicular Parameters

2015 ◽  
Vol 5 (4) ◽  
pp. 141-148
Author(s):  
Olumuyiwa Joseph Olarotimi ◽  
◽  
Olujide Adedamola Sokunbi ◽  
Abdur-Rahman Abdullah ◽  
◽  
...  
Keyword(s):  
Oryctolagus Cuniculus ◽  
Sperm Production ◽  
Daily Sperm Production

scholarly journals Seasonality of Coxiella burnetii among Wild Rabbits (Oryctolagus cuniculus) and the Hyalomma lusitanicum (Acari: Ixodidae) in a Meso-Mediterranean Ecosystem

Pathogens ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 36
Author(s):  
María Sánchez ◽  
Félix Valcárcel ◽  
Julia González ◽  
Marta G. González ◽  
Raquel Martín-Hernández ◽  
...  
Keyword(s):  
Coxiella Burnetii ◽  
Cervus Elaphus ◽  
Oryctolagus Cuniculus ◽  
Red Deer ◽  
Q Fever ◽  
Mediterranean Ecosystem ◽  
Wild Rabbit ◽  
Sylvatic Cycle ◽  
Almost Everywhere ◽  
In The Wild

(1) Background: Q fever is a worldwide zoonosis caused by Coxiella burnetii that have cases reported in humans and animals almost everywhere. The aim of this study was to describe the seasonality of Coxiella burnetii in the wild rabbit (Oryctolagus cuniculus) and the tick Hyalomma lusitanicum in a meso-Mediterranean ecosystem. (2) Methods: two populations of wild rabbits that differ in whether or not they share habitat with ungulates, mainly red deer (Cervus elaphus) were sampled for a year to collect ticks, blood and vaginal or anal swabs. Presence of C. burnetii DNA in swabs and the tick H. lusitanicum was determined by PCR and serum antibodies by ELISA. (3) Results: C. burnetii DNA was detected in 47.2% of 583 rabbits, in 65.5% of sera, and in more than half of the H. lusitanicum. There were small variations according to sex and age of the rabbits but significant according to the habitat (4) Conclusions: The results indicate that C. burnetii circulates freely between wild rabbits and H. lusitanicum and the sylvatic cycle in meso-Mediterranean environments relies in the presence of wild rabbits and H. lusitanicum above all if sharing habitat with red deer.

scholarly journals Spermatogenesis: The Commitment to Meiosis

2016 ◽  
Vol 96 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Michael D. Griswold
Keyword(s):  
Reduction Division ◽  
Seminiferous Epithelium ◽  
Seminiferous Tubules ◽  
Sperm Production ◽  
Morphological Transformation ◽  
Time Required ◽  
Relationship Of ◽  
Synthesis And Degradation ◽  
Daily Sperm Production ◽  
Stem Cell Pool

Mammalian spermatogenesis requires a stem cell pool, a period of amplification of cell numbers, the completion of reduction division to haploid cells (meiosis), and the morphological transformation of the haploid cells into spermatozoa (spermiogenesis). The net result of these processes is the production of massive numbers of spermatozoa over the reproductive lifetime of the animal. One study that utilized homogenization-resistant spermatids as the standard determined that human daily sperm production (dsp) was at 45 million per day per testis (60). For each human that means ∼1,000 sperm are produced per second. A key to this level of gamete production is the organization and architecture of the mammalian testes that results in continuous sperm production. The seemingly complex repetitious relationship of cells termed the “cycle of the seminiferous epithelium” is driven by the continuous commitment of undifferentiated spermatogonia to meiosis and the period of time required to form spermatozoa. This commitment termed the A to A1 transition requires the action of retinoic acid (RA) on the undifferentiated spermatogonia or prospermatogonia. In stages VII to IX of the cycle of the seminiferous epithelium, Sertoli cells and germ cells are influenced by pulses of RA. These pulses of RA move along the seminiferous tubules coincident with the spermatogenic wave, presumably undergoing constant synthesis and degradation. The RA pulse then serves as a trigger to commit undifferentiated progenitor cells to the rigidly timed pathway into meiosis and spermatid differentiation.

scholarly journals Disruption of sexual function, FSH secretion, and spermiogenesis in rabbits following developmental exposure to vinclozolin, a fungicide

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 805-816 ◽  
Author(s):  
D N R Veeramachaneni ◽  
J S Palmer ◽  
R P Amann ◽  
C M Kane ◽  
T T Higuchi ◽  
...  
Keyword(s):  
Sexual Maturity ◽  
Low Dose ◽  
Seminiferous Tubules ◽  
Testicular Descent ◽  
High Dose ◽  
Sperm Production ◽  
Developmental Exposure ◽  
Serum Lh ◽  
Women And Children ◽  
Daily Sperm Production

We studied sequelae of prenatal plus infantile exposure of male rabbits to vinclozolin, because it is ingested by women and children. Female Dutch-Belted rabbits (7–10/group) were treated daily per orum from gestation day 15 through post-natal week 4 to provide 0, 7.2, or 72 mg vinclozolin/kg dam’s body weight/day. Vinclozolin had no effect on maintenance of pregnancy, growth of pups, age at testicular descent or weight of organs. Concentrations of serum LH or testosterone at 6, 12, or 24 weeks of age were unaffected. However, FSH was lower (P< 0.05) in both vinclozolin groups at all three ages. Following injection of GnRH at 12 or 24 weeks, the increase in FSH was less (P< 0.05) in both vinclozolin groups, as was testosterone at 12 weeks of age. After full sexual maturity, 2 of 7 low dose rabbits were uninterested in female or male teasers and never achieved erection or ejaculation. Overall, rates of ejaculation failure were: control 0% (0/48), low dose 29% (12/42), and high dose 5% (3/60). Daily sperm production per gram of testis and total number of sperm per ejaculate in both vinclozolin groups were similar (P> 0.1) to controls. However, semen from vinclozolin rabbits contained over two times more (P< 0.05) morphologically abnormal spermatozoa, mostly nuclear and acrosomal defects, than semen from controls. Seminiferous tubules with degenerative changes were more frequent (P< 0.05) in vinclozolin rabbits than in controls. Lesions included syncytia of spherical spermatids and desquamation of germ cells. Hence, developmental exposure to vinclozolin caused presumably permanent changes in copulatory ability, secretion of FSH, and spermiogenesis.

scholarly journals Intra-uterine mortality of the wild rabbit, oryctolagus cuniculus (L.)

1942 ◽  
Vol 130 (861) ◽  
pp. 462-479 ◽  
Keyword(s):  
Body Weight ◽  
Breeding Season ◽  
Oryctolagus Cuniculus ◽  
Size Class ◽  
Corpora Lutea ◽  
Wild Rabbit ◽  
Initial Size ◽  
Class A ◽  
Stage Of Development ◽  
Geometrical Progression

The paper deals with a sample of 185 pregnant rabbits obtained in Caernarvonshire between February and July 1941 inclusive, during the height of the breeding season. The intra-uterine mortality was estimated by comparison of the number of corpora lutea in the ovaries with the number of healthy embryos in the uteri. By grouping the data according to the stage of development of the embryos, it is shown that between 42 and 56% of all litters are lost before the 20th day of gestation. This enormous mortality occurs chiefly on the 11th and 12th days of gestation, after implantation and when the placenta is already well established. Analysis of the mortality according to the initial size of litter shows that the proportion of litters showing loss increases with the initial size of the litter in the form of a geometrical progression. In almost every litter-size class a relatively large number of litters were observed in which all the embryos were reabsorbing. The mortality, whether represented by the percentage of animals showing loss or by the percentage of ova lost, also varies according to ( a ) whether the animals are, or are not, lactating, ( b ) the cleaned body weight of the mother, and ( c ) the month. These variations are, however, fully accounted for by variations in the frequencies of the initial size of litter.

Reproductive effects of endosulfan on male offspring of rats exposed during pregnancy and lactation

1999 ◽  
Vol 18 (9) ◽  
pp. 583-589 ◽  
Author(s):  
P R Dalsenter ◽  
E Dallegrave ◽  
J Rb Mello ◽  
A Langeloh ◽  
R T Oliveira ◽  
...  
Keyword(s):  
Male Offspring ◽  
Male Rats ◽  
Male Rat ◽  
Seminiferous Tubules ◽  
Sperm Production ◽  
Rat Offspring ◽  
Stage Of Development ◽  
Reproductive Effects ◽  
Pregnancy And Lactation ◽  
Daily Sperm Production

1 The reproductive effects of endosulfan on the male offspring of rats were examined. Dams were treated orally with 0, 1.5 or 3.0 mg endosulfan/kg from day 15 of pregnancy to postnatal day (PND) 21 of lactation. The male offspring rats were investigated at PND 65 or 140, corresponding to the pubertal and adulthood stage of development. 2 The dose of 3.0 mg endosulfan/kg induced a decrease in maternal body weight during pregnancy, but litter size and mean birth weight were not affected. Similarly, the age at testis descent and preputial separation was not affected on the male offspring. 3 The daily sperm production (6106) was permanently decreased in the highest dose group when investigated at puberty and at adulthood. At the lowest dose, however, the daily sperm production was significantly reduced only at puberty. 4 Histologically, the percentage of seminiferous tubules showing complete spermatogenesis was significantly decreased at puberty. This finding may explain the decrease in daily sperm production observed in the endosulfan-exposed male rats. 5 The results of this study show that low doses of endosulfan have no apparent effect on developmental landmarks or on the weight of reproductive and accessory sex organ. Daily sperm production was the most susceptible endpoint in the male offspring exposed to endosulfan during pregnancy and lactation. To further understand the reproductive effects of endosulfan on male rat offspring, additional reproductive and toxicokinetic studies should be carried out to determine the extent of endosulfan exposure in male rat offspring in utero and during lactation.

scholarly journals Chronic exposure of bisphenol S (BPS) affect hypothalamic-pituitary-testicular activities in adult male rats: possible in estrogenic mode of action

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Hizb Ullah ◽  
Faizan Ullah ◽  
Owais Rehman ◽  
Sarwat Jahan ◽  
Tayyaba Afsar ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Chronic Exposure ◽  
Structural Changes ◽  
Gonadosomatic Index ◽  
Male Rats ◽  
Plasma Testosterone ◽  
Seminiferous Tubules ◽  
Sperm Production ◽  
Bisphenol S ◽  
Daily Sperm Production

Abstract Background The industrial revolution has resulted in increased synthesis and the introduction of a variety of compounds into the environment and their potentially hazardous effects have been observed in the biota. The present study was aimed to evaluate the potential endocrine-disrupting effects of chronic exposure to the low concentrations of bisphenol S (BPS) in male rats. Methods Weaning male Sprague-Dawley rats (22 days old) were either exposed to water containing 0.1% ethanol for control or different concentrations of BPS (0.5, 5, and 50 μg/L) in drinking water for 48 weeks in the chronic exposure study. After completion of the experimental period, animals were dissected and different parameters (hormone concentrations, histology of testis and epididymis, oxidative stress and level of antioxidant enzymes in the testis, daily sperm production (DSP), and sperm parameters) were determined. Results Results of the present study showed a significant alteration in the gonadosomatic index (GSI) and relative reproductive organ weights. Oxidative stress in the testis was significantly elevated while sperm motility, daily sperm production, and the number of sperm in epididymis were reduced. Plasma testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) concentrations were reduced and estradiol levels were high in the 50 μg/L-exposed group. Histological observations involved a significant reduction in the epithelial height of the testis along with disrupted spermatogenesis, an empty lumen of the seminiferous tubules, and the caput region of the epididymis. Conclusion These results suggest that exposure to 5 and 50 μg/L of BPS for the chronic duration started from an early age can induce structural changes in testicular tissue architecture and endocrine alterations in the male reproductive system which may lead to infertility in males.

Duration of spermatogenesis and daily sperm production in the rodent Proechimys guyannensis

Zygote ◽  
2016 ◽  
Vol 24 (5) ◽  
pp. 783-793 ◽  
Author(s):  
Nathália L.M. Lara ◽  
Ivan C. Santos ◽  
Guilherme M.J. Costa ◽  
Dirceu A. Cordeiro-Junior ◽  
Antônio C. G. Almeida ◽  
...  
Keyword(s):  
Leydig Cells ◽  
Gonadosomatic Index ◽  
Cell Types ◽  
Seminiferous Tubules ◽  
Testis Weight ◽  
Sperm Production ◽  
The Mean ◽  
Neotropical Rodent ◽  
Very High ◽  
Daily Sperm Production

SummaryThe spiny rat (Proechimys guyannensis) is a neotropical rodent that is used in biomedical research, particularly research related to chronic resistance to epilepsy and infectious diseases. To our knowledge, there are few reports concerning the reproductive biology of this species. Therefore, besides providing basic biometric and morphometric data, in the present study we investigated testis function and spermatogenesis in adult spiny rats. The mean testis weight and gonadosomatic index obtained were 1.63 ± 0.2 g and 1.15 ± 0.1% respectively. Based on the development of the acrosomic system, 12 stages of the seminiferous epithelium cycle were characterized. Stages VI and VII presented the highest frequencies (~17–19%), whilst stages II to V showed the lowest frequencies (~2–4%). The most advanced germ cell types labelled at 1 h or 20 days after BrdU injections were respectively preleptotene/leptotene spermatocytes at stage VII and elongated spermatids at stage III. The mean duration of one cycle was 7.5 ± 0.01 days and the entire spermatogenic process lasted 33.7 ± 0.06 days (~4.5 cycles). The seminiferous tubules (ST) occupied ~96 ± 1% of the testis parenchyma, whereas Leydig cells comprised only 1.5 ± 0.4%. The number of Sertoli cells (SC) per testis gram and the SC efficiency (spermatids/SC) were respectively 78 × 106 ± 11 × 106 and 7.9 ± 1. The daily sperm production per testis gram (spermatogenic efficiency; daily sperm production (DSP)/g/testis) was 78 × 106 ± 8 × 106. To our knowledge, this spermatogenic efficiency is among the highest found for mammals investigated to date and is probably related to the very short duration of spermatogenesis and the very high ST percentage and SC number obtained for this species.

Environmental factors have little influence on the reproductive activity of the Iberian hare (Lepus granatensis)

2003 ◽  
Vol 30 (6) ◽  
pp. 639 ◽  
Author(s):  
P. C. Alves ◽  
A. Rocha
Keyword(s):  
Environmental Factors ◽  
Seasonal Pattern ◽  
Reproductive Activity ◽  
Lepus Europaeus ◽  
Climatic Data ◽  
Regression Equations ◽  
Wild Rabbit ◽  
European Hare ◽  
Pregnant Females ◽  
Iberian Hare

The two European hare species with the largest ranges, the brown hare (Lepus europaeus) and the mountain hare (L. timidus), have a marked seasonal pattern of reproduction, probably reflecting strong environmental influences during the year. In this work, we evaluate the role of some environmental factors on the reproductive activity of another European hare species, the Iberian hare (L. granatensis). The study was carried out in Pancas, southern Portugal, from mid-1997 through December 1999. Climatic data (mean monthly values of minimum and maximum air temperature, daylength and total monthly rainfall) were recorded at the nearest meteorological station. To assess abundance and quality of food, samples of the herbaceous vegetation were collected every two months and analysed for water, fibre and crude protein content. Iberian hares were collected every two months and live or post mortem analyses were performed. The proportion of males with external testes and of pregnant females as well as the weight of the gonads were recorded. While environmental variables had marked seasonal variations, the Iberian hare nevertheless showed continuous reproductive activity. In all sampled periods, males with external testes and pregnant females were observed. However, a slight decrease of sexual activity appears to occur, mainly in males, during autumn. Only the variation of male reproductive characteristics was significantly explained by multiple regression equations. Maximum regression coefficients were obtained with the climatic variables (minimum, maximum temperatures and daylength) and vegetation biomass of the preceding two months. Our data indicate that environmental factors have little effect on reproduction in the Iberian hare. The results are compared with those obtained for other phylogenetically and geographically close hare species, and with another leporid, the wild rabbit (Oryctolagus cuniculus algirus), which occurs sympatrically with L. granatensis.

scholarly journals Testis structure, duration of spermatogenesis and daily sperm production in four wild cricetid rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes)

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251256
Author(s):  
Dirceu A. Cordeiro ◽  
Guilherme M. J. Costa ◽  
Luiz R. França
Keyword(s):  
Environmental Changes ◽  
Gonadosomatic Index ◽  
Mammalian Species ◽  
Rodent Species ◽  
Seminiferous Tubules ◽  
Sperm Production ◽  
Wild Rodents ◽  
Rats And Mice ◽  
Very High ◽  
Daily Sperm Production

Although rodents represent approximately 40% of all living mammalian species, our knowledge regarding their reproductive biology is still scarce. Due to their high vulnerability to environmental changes, wild rodents have become beneficial models for ecological studies. Thus, we aimed to comparatively investigate key functional testis parameters in four sexually mature wild rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes). These species belong to the Cricetidae family, which is the most diverse family of rodents in South America, with a total of ~120 species in Brazil. The results found for the gonadosomatic index and the sickled sperm head shape observed strongly suggest that the species here evaluated are promiscuous, prolific, and short-lived. The duration of spermatogenesis was relatively short and varied from ~35–40 days. Both the percentage of seminiferous tubules (ST) in the testis parenchyma (~95–97%) and the number of Sertoli cells (SC) (~48–70 million) per testis gram were very high, whereas a fairly good SC efficiency (~8–13 round spermatids per SC) was observed. In comparison to other mammalian species studied, particularly the rodents of the suborder Myomorpha (i.e. hamsters, rats and mice), the rodents herein investigated exhibited very high (~62–80 million) daily sperm production per testis gram. This impressive spermatogenic efficiency resulted mainly from the short duration of spermatogenesis and quite high values found for the ST percentage in the testis and the SC number per testis gram. We expect that the knowledge here obtained will help conservation programs and the proper management of wildlife.

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