Reproduction

doi: 10.1530/jrf.0.0230375-apmid: N/A

J. P. Polidoro and D. L. Black (1970) Peripheral plasma progesterone and the number of foetuses in normal and superovulated rabbits. J. Reprod. Fert. 22, 493.Page 496, Table 2. The standard errors require correction and the Table should read as follows:

HALEY, L. E.; ABPLANALP, H.

doi: 10.1530/jrf.0.0230375pmid: 5492024

Summary.Female quail from populations selected for high interspecific fertility when bred with fowl were inseminated half-weekly with fowl semen for periods up to 18 consecutive weeks. At the end of that time, all birds showed a decline in interspecific fertility and the blood plasma of approximately half of the female quail contained antibodies against fowl spermatozoa. The interspecific fertility of these birds was considerably less than that of the birds which did not have antibodies.In a second experiment, female quail with high interspecific fertility were given an intravenous injection of fowl semen. Their interspecific fertility was approximately 10% lower than a control group of female quail.

ROSENMANN, E.; DISHON, T.; DURST, A.; BOSS, J. H.

doi: 10.1530/jrf.0.0230383pmid: 4992610

Summary.Patterns of distribution of organ-specific antigens in the accessory sex glands of the male rat and the urinary excretion of these antigens were investigated by the immunodiffusion and immunofluorescence microscopical techniques. One organ-specific antigen was detected in the bulbo-urethral gland, two antigens were found in the prostatic gland and three common ones in the ampullary gland, seminal vesicle and coagulating gland. The antigens were localized immunohistologically in the epithelial cytoplasm and luminal excretory products of the glands. The antigens of the accessory glands were demonstrated in the urine, the only exception being the antigen of the bulbo-urethral gland. There were irregular variations in the urinary excretion of the antigens of the individual glands. The prostatic constituents were found to be the main contributors of the accessory glands to the urinary protein pool.

ROOD, J. P.; WEIR, BARBARA J.

doi: 10.1530/jrf.0.0230393pmid: 5492025

Summary.The breeding characteristics of three species of wild guineapig (F. Caviidae) are reported. Cavia aperea, Galea musteloides and Microcavia australis were studied in Argentina in the field and in outdoor pens, and laboratory colonies of the two former species were also established in England. Pens of domestic guinea-pigs (Cavia porcellus) and of C. aperea × C. porcellus hybrids were maintained in Argentina for comparisons with C. aperea.C. aperea and G.musteloides gave birth in every month but there was a breeding peak in spring (September to December). Microcavia had a more restricted breeding season ; in the field study area, births occurred only between August and April. Gestation length in C. aperea was variable but the mode was at 61 days, while the modes of Galea and Microcavia were much shorter at 53 and 54 days, respectively. All three species exhibited a post-partum oestrus and Galea may experience a lactation anoestrus. Oestrous cycle lengths in C. aperea and Galea varied considerably but the mean length in Cavia was 20·6±0·8 days and in Galea it was 22·3±12·4 days; in the latter species, the presence of a male in the same cage was necessary for the induction of oestrus. Average litter size was 2·2 for C. aperea, 2·6 for Galea and 2·8 for Microcavia. In the Argentine colonies, the age at first conception in C. aperea and Galea varied with the time of year of birth, but this variation was not maintained under the more equable laboratory conditions.

RAKHA, A. M.; IGBOELI, G.; HALE, D.

doi: 10.1530/jrf.0.0230411pmid: 5531081

Summary.A total of 333 oestrous cycles was observed in fifty-five sexually mature cattle of Central African breeds. Silent ovulation accounted for 13% of the cycles. The normal cycle lengths averaged 21·89±1·64, 22·68±3·68 and 24·25±2·27 days for the Angoni, Barotse and Boran breeds, respectively. The lengths of the corresponding oestrous periods were 16·26±1·08, 17·43±1·18 and 14·79±3·03 hr. Ovulation occurred 31·50±1·45 hr from the time of onset of oestrus. Most animals came into heat around sunrise and sunset. Cervical changes were photographed.

SCOTT, R. S.; RENNIE, P. I. C.

doi: 10.1530/jrf.0.0230415pmid: 5492026

Summary.The life-span of corpora lutea (cl) of varying ages within the one rabbit was studied by an experimental procedure in which 2-day-old cl removed from donor rabbits were transferred beneath the kidney capsule of recipient rabbits. Within oestrous recipients, the cl were found to have a total life-span of approximately 17 days, which was similar to that of ovarian cl in the pseudopregnant rabbit. When the cl were transferred into 12-day pseudopregnant rabbits, their life-span was reduced to approximately 11 days and both the ovarian and transferred cl regressed at approximately the same time. It was suggested that a uterine factor may have caused the early regression of the transferred cl since hysterectomy at the time of transfer prolonged the life-span of each set of cl to approximately 23 to 27 days. In these animals, the cl regressed asynchronously.Prostaglandin F2α caused early regression of the ovarian cl when given to hysterectomized rabbits.

CUMMINS, J. M.; GLOVER, T. D.

doi: 10.1530/jrf.0.0230423pmid: 4099419

Summary.Artificial cryptorchidism produced sterility in male rabbits within 7 days. Progressive infertility, which first appeared on the 2nd day after operation, resulted from a failure of a normal number of live motile spermatozoa to fertilize. Many such spermatozoa had not discarded their cytoplasmic droplets, and it is thought that these were heat-affected and incapable of fertilization. This is because fertilization rate and implantation rate were significantly (P<0·001) correlated with the number of live (droplet-free) spermatozoa in the inseminates.There were no adverse effects on the ability of embryos to implant or to survive gestation, and the morphology and sex ratio of foetuses at term were normal. Before fertilization failure became apparent, there were significant (P<0·001) improvements in embryonic survival rates and a theory is advanced to explain these findings.

BROOKS, P. H.; COLE, D. J. A.

doi: 10.1530/jrf.0.0230435pmid: 5531082

Summary.Groups of gilts of similar age, weight and breeding were allocated at 165 days of age to four treatments. One group of gilts was isolated from boars throughout the experiment. Fewer animals reached puberty during the experiment in this group than in the other groups where boars were introduced. Introduction of a boar to gilts at 165 or 190 days of age resulted in precipitation of oestrous activity. At 165 days, considerable synchrony of oestrus was obtained when there was a rotation of the boars used for testing, but the effect was much less marked when only one boar was used.

FRANKEL, A. I.; EIK-NES, K. B.

doi: 10.1530/jrf.0.0230441pmid: 4250040

Summary.Testosterone and dehydroepiandrosterone were present in higher concentration in the caput than in the cauda epididymidis of the rabbit. Although testosterone levels were higher in the testis than in the caput epididymidis, dehydroepiandrosterone levels were not. This distribution of steroids could help explain data recording localization of sperm fertility in this organ.

BREED, W. G.; CLARKE, J. R.

doi: 10.1530/jrf.0.0230447pmid: 5492027

Summary.In the vole, Microtus agrestis, there was no significant change in the number of corpora lutea (cl) during either pregnancy or pseudopregnancy. In pregnant animals, two waves of luteal development took place and histological changes during the two phases of growth differed. In pseudopregnant animals, a similar increase occurred initially which was followed by a marked decrease after Day 8, at which time cl began to degenerate. Luteinized follicles were visible early in pregnancy and pseudopregnancy. Graafian follicles were present after Day 2 or 3. In pregnant animals, the number remained more or less constant, except for a slight increase on Day 19, but their maximum size was reduced at about mid-term, whereas, in pseudopregnant animals, a marked increase in size occurred between Days 8 and 10. Vaginal smears and histology indicated progesterone secretion up to Day 19 of pregnancy and for the 8 to 9 days of pseudopregnancy. There was, therefore, a good correlation between the presence of healthy cl and smears that indicated progesterone secretion.