The time of ovulation and efficiency of fertilization following progesterone and pregnant mare serum treatment in the cyclic ewe

Robinson, T. J.

doi:10.1017/s0021859600050103

Cited by 17 publications

(6 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The continued difficulties in obtaining adequate fertility after hormonal synchronisation imply a breakdown somewhere in the chain of events. For instance, progesterone synchonisation caused higher incidence of abnormal ova in one study (Foote and Waite 1965), and Robinson (1961) recovered fewer fertilised ova from synchronised ewes.…”

Section: The Effect Of Oxytocin In Sperm Transportmentioning

confidence: 96%

Distribution of spermatozoa in the reproductive tract of the Romney ewe

Lang¹,

Ohf

1970

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

The ampulla, isthmus, uterus, and cervix of mixed-age Romney ewes were examined for the presence of spermatozoa 1, 2, 4, 8, 16, 24, 36, and 48 hrs after a single mating. Spermatozoa were recovered from the following sites at the stated intervals after copulation: the cervix 1 hr, the uterus 2 hrs, the isthmus 4 hrs, and the lower ampulla 16 hrs. Peak numbers in all regions occurred 16 hrs after mating. Cervical numbers were noticeably constant up to 16 hrs and then began to fall.Spermatozoa disappeared rapidly from the reproductive tract between 36 and 48 hrs after copulation, probably because of recommencement of normal dioestral flows of luminal fluids.Oxytocin (lI.U.) administered 3t hrs after copulation enhanced the number of spermatozoa reaching the lower ampulla. Synchronisation of oestrus with progesterone appeared to inhibit both the rate of transport of spermatozoa in ewes and the number entering the uterus and isthmus. These findings based on only a small number of animals are discussed in the light of present knowledge on sperm transport in the ewe.

show abstract

Section: The Effect Of Oxytocin In Sperm Transportmentioning

confidence: 96%

Distribution of spermatozoa in the reproductive tract of the Romney ewe

Lang¹,

Ohf

1970

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

show abstract

“…(MARDEN, 1952 a;AVERY und Mitarbeiter, 1962;JAINUDEEN und Mitarbeiter, 1966 (MOORE und SHELTON, 1964). Ebenso wie beim Rind konnen auch beim Schaf nach Zyklussynchronisation mit Progestagenen Polyovulationen durch FSH hervorgerufen werden (ROBINSON, 1961(ROBINSON, , 1965.…”

Section: Polyovulation Vor Der Geschlechtsreifeunclassified

Polyovulation bei Haustieren

Hafez

1969

Zeitschrift für Tierzüchtung und Züchtungsbiologie

View full text Add to dashboard Cite

“…Much information is available to show that ova shed in response to progesteronep.M.s. therapy are capable of fertilization and that they undergo normal cleavage subsequently (Averill, 1958;Robinson, 1961). Some have suggested that different methods of progesterone-p.M.s.…”

Section: Conceptionmentioning

confidence: 99%

The induction of pregnancy in the anoestrous ewe by hormonal therapy V. Progesterone-pregnant mare's serum therapy on Clun forest maiden sheep and general conclusions

Gordon

1963

J. Agric. Sci.

View full text Add to dashboard Cite

In a previous paper (Gordon, 19586) results were given on the application of progesterone-p.M.s. therapy in out-of-season breeding which showed that non-lactating ewes conceived more readily than lactating animals. In the trials with ' dry' sheep the most promising results, in terms of conception percentage, were noted in maiden yearling ewes. While results given earlier in this series (Parts II and III) suggest that a solution to the problem of out-ofsoason breeding, especially in lactating ewes, may lie in the use of repeated progesterone-p.M.s. therapy, there is some doubt whether such extended therapy is justifiable in applications to yearling (maiden) animals. Obviously, if there is strong evidence that a satisfactory practical result follows standard (single course) treatment, such information would be useful to the flock-owner. Trial 1The present work was to provide further information on the response of the maiden ewe, and to establish some of the reasons why this category of animal usually shows a better conception percentage than either mature 'dry' or lactating ewes. The work was restricted to animals of the Clun Forest breed, this being an obvious choice of sheep which flock-owners would use in out-of-season breeding. MATERIAL AND METHODSSheep. Experiments were undertaken in two flocks of Clun maiden ewes, made available by two co-operating farmers in Hampshire in 1958. A total of seventy-six was involved (flock 45, forty-seven ewes; flock 46, twenty-nine ewes), the sheep being approximately 1 year old and not previously exposed to the ram. Ten Clun rams were used in the matings (five per flock).Hormones and method of administration. Progesterone was used as an oil solution, 1 ml. containing 10 mg.; the solution was given intramuscularly.A freeze-dried preparation of P.M.S. was subcutaneously injected in all treatments.Treatment and field procedure. Treatment consisted of three doses of 50 mg. progesterone administered at intervals of 3 days; 750 i.u. of P.M.S. was given 2 days after the final progesterone injection. Injections commenced 29 March in flock 45 and 3 April in flock 46. In each instance, treatment was applied simultaneously to all animals.In flock 45, the first part of the experiment consisted of observations on the incidence of spontaneous oestrus in the Clun yearling ewe during the latter part of the normal breeding season. Two rams were 'raddled' and introduced among the fortyseven ewes on 10 February. Daily inspection for matings was made for a 47-day period which ended 29 March, the time at which hormone treatment commenced.The full complement of rams joined each flock following administration of P.M.S. All rams were ' raddled' and a daily record of matings maintained for a period of 2 weeks after the end of hormone treatment. Sheep were identified by plastic eartags, and prominently marked on the fleece for easy field recognition. The sheep on each farm were kept together in the one group for the period of pregnancy. They were on grass for the period of the experiment; no suppleme...

show abstract

The time of ovulation and efficiency of fertilization following progesterone and pregnant mare serum treatment in the cyclic ewe

Cited by 17 publications

References 13 publications

Distribution of spermatozoa in the reproductive tract of the Romney ewe

Distribution of spermatozoa in the reproductive tract of the Romney ewe

Polyovulation bei Haustieren

The induction of pregnancy in the anoestrous ewe by hormonal therapy V. Progesterone-pregnant mare's serum therapy on Clun forest maiden sheep and general conclusions

Contact Info

Product

Resources

About