Showing papers in "Theriogenology in 1977"

TL;DR: The sex ratio for cows requiring one insemination per pregnancy was not different from repeat breeders it is suggested that the sex ratio at fertilization and birth may be similar.

TL;DR: Clinical, morphologic and hormonal changes throughout the estrous cycle in the dog are discussed in relation to the well established stages in this species — proestrus, estrus, metestrus and anestrus to characterize the dog as a monocyclic animal in contrast to polycyclic species.

TL;DR: It was concluded that egg production could limit the application of egg transfer as some animals seem to be unable to respond to the usual PMS/PG treatment used and those that have a satisfactory response retain this response for only a limited number of treatments.

TL;DR: The measurement of total plasma oestrogens (conjugated and unconjugated) gives 100 times higher levels than the specific measurement of 17β oestradiol, which gives a good picture of the follicular activity of the mare.

TL;DR: A gonadoliberin (GnRH) analogue nonapeptide (Hoe 766) was administered intramuscularly in concentrations between 25 and 50 μg to cows in order to study the response of lutropin (LH) and follitropin(FSH) as discussed by the authors.

TL;DR: It was concluded that the most common cause of abnormal sexual behavior was mismanagement, such as excessive use, abusive training procedures, injuries during breeding, etc.

TL;DR: One or two 6–7 or 9–10 day old blastocysts were transferred to 39 pure-bred or cross-bred Charolais heifer recipients and an insemination catheter was used to transfer the blastocyst through the cervix into the uterus.

TL;DR: A simple one-way cannula technique for non-surgical recovery of bovine embryos has been described and could be guided through cervix and without damage to the genital tract into both uterine horns on all attempts.

TL;DR: Embryos were recovered surgically 4 to 6 days after onset of estrus from superovulated donor cows in which estrus had been synchronized by long-term progestin treatment to determine eggs considered to be at a stage of development consistent with the donor's stage of the estrous cycle.

TL;DR: The occurrence of anovulatory estrus in three different groups of animals suggests that it is common in the first breeding season of young ewes, and Lambing percentage probably is reduced below the expected level by the presence in the flock of ewe lambs that have had an estrus but not yet reached puberty.

TL;DR: Plasma hormone levels were determined at frequent intervals in 12 two-year-old Hereford heifers after treatment with prostaglandin F2α on day 267 of gestation to induce parturition and it was found that the treatment with PGF2α was effective since the treated heifer calved a mean of 12 days sooner than the untreated heIFers (P < .01).

TL;DR: Prostaglandin F 2α produced abortion 1 to 4 days following direct administration into the foetai fluids, and plasma progesterone concentration fell rapidly within one day of administration to approximately 2 ng/ml, at which concentration abortion took place.

TL;DR: It appears that the incidence of repeat breeder cows is influenced by nutritional factors, particularly by the roughage, protein, and energy levels, which is essential for providing appropriate fertility levels in high producing dairy herds.

TL;DR: Treatment with both steroids was associated with early cleavage forms which were absent in the untreated animals and the implications of this finding in relation to fertility depression in heifers treated with SC9880 or SC21009 for 21 days is discussed.

TL;DR: Concentrations of testosterone and luteinizing hormone (LH) but not prolactin were decreased significantly after the first hour, but not testosterone in plasma decreased (P).

TL;DR: Induction of parturition shortened gestation length and increased the incidence of retained placentas (both P) and the effectiveness of estradiol benzoate in combination with dexamethasone on traits atParturition and on productive and reproductive characteristics following parturitions was determined.

TL;DR: The efficiency of a synthetic prostaglandin analog for the control of the estrus cycle in dairy cows has been tested with and without simultaneous use of progestagen implants.

TL;DR: Data is presented which shows that neonatal isoerythrolysis (NI) is not involved in the death of the white foals, and further research is needed to define the nature of the lethal anomaly, as well as the genetics, of overo and lethal white foal.

TL;DR: The results from this experiment suggest that estrogen pretreatment of randomly cycling gilts for 20 days followed by PGF 2α is an effective estrus and ovulation control regime.

TL;DR: A 10-year-old multiparous Holstein cow with an ovarian tumor showed signs of nymphomania, followed by anestrus and virilism, and the cow, bred three months later, conceived.

TL;DR: It is suggested that D-ala-GnRH administered 64 h after the luteolytic dose of PGF 2α is an effective means of synchronization of preovulatory LH surges and may be a valuable aid in improving fertility to a single insemination in P GF 2α -synchronized beef cows.

TL;DR: None of the variables studied had a significant effect on the occurrence of estrus or the interval between treatment and the onset of heat.

TL;DR: After intrauterine inoculation of Mycoplasma canis in female dogs, the influence on uterus and general state of health was investigated using clinical, gynecological, microbiological and pathohistological methods and an enlargement of the uterus could be found at post mortem.

TL;DR: Examination of the repeatability of penetration into the uterus through the cervical canal by the technique for non-surgical intrauterine insemination in the ewe found it could select those ewes to be inseminated with expensive deep-frozen semen to improve the fertility rate.

TL;DR: Two closed lines of sheep selected for high and low prolificacy were established in 1969 and there was no difference in ovulation rate or fertilization rate of ewes mated to low and high line rams.