A study was done to evaluate the effect of using progesterone (P4) intravaginal device (CIDR: controlled internal drug-releasing dispenser) to synchronise the return to oestrus of previously timed inseminated (TAI) dairy heifers, and to evaluate embryo survival and pregnancy rate (PR) in the return to oestrus heifers. At the onset of the artificial insemination (AI) breeding period (day -9), he...

The kisspeptin/Gpr54 signaling pathway plays a critical role in reproduction by stimulating the secretion of GnRH, yet mice carrying mutations in Kiss1 (which encodes kisspeptin) or Gpr54 exhibit partial sexual maturation. For instance, a proportion of female Kiss1−/− and Gpr54−/− mice exhibit vaginal oestrus, and some male Kiss1−/− and Gpr54−/− mice exhibit spermatogenesis. To characterise thi...

A total of 16 crossbred repeat breeder cows were treated with norgestomet (Syncromate-B) ear implants for nine days. At the time of implant insertion, two ml of SMB injection was adminisetred to all the cows intramuscularly on day 10 of the oestrous cycle to induce oestrus. AI was done at 48 and 72 h after implant removal. Pregnancy diagnosis was done at 60 days following AI after induced oestr...

The effects of acceleration and delay of puberty in female house mice on survival and reproduction were tested using 6 experimental groups: (1) control females mated at the time of first oestrus, (2) females mated at weaning, (3) females treated with male urine starting at weaning and mated at first oestrus, (4) females housed in groups and mated at first oestrus, (5) females housed alone, trea...

In October, 1964, beef cows were divided into three groups. One group was run with bulls for four months (group 1); another group was kept free of bulls and was observed daily for six weeks and cows detected in oestrus were inseminated using chilled semen (group 2); and the third group was given progestagens to synchronise ovarian cycles and the cows were inseminated after treatment and again a...

The effects of prostaglandin F2\g=a\on peripheral plasma progesterone and oestrogen levels, incidence of oestrous cycle alteration, and fertility were examined in thirty beef heifers. The PGF2\g=a\was administered by insertion of an insemination pipette into the lumen of the uterus during three periods of the oestrous cycle: Days 3 to 5, Days 9 and 10, and Days 16 and 17. Oestrus occurred withi...

the present study was conducted to see the effect of non-specific genital infections and ovulatory disturbances on clinical signs of oestrusnamely oestrus duration, tonicity of uterus, relaxation of cervix and persistence of follicle. the mean values of oestrus duration, tonicity of uterus and relaxation of cervix varied significantly (p

The first ovulation and first oestrus after parturition were recorded in four groups of Merino ewes which: (a) reared their lambs normally, (b) were allowed to suckle their lambs only during three 1-hr periods each day, (c) had their lambs removed on the day after birth, or (d) had their lambs removed on the day after birth and were injected intramuscularly with 5 i.u. oxytocin ten times each d...

Eosinophils, macrophages and other leucocytes invade the uterine endometrium during oestrus and play a role in the tissue remodeling and immune responses that occur prior to implantation of the fertilized ovum. Adenosine 5'-triphosphate (ATP) and its metabolites influence uterine function via ATP receptors. In this study, we investigated the presence and localisation of the P2X(7) nucleotide re...

A trial was conducted to study the effect of presence of the boar on the attainment puberty in gilts and the feasibility and economics of rearing pigs of either sex together. Sixteen weaned Large White Yorkshire gilts, twelve weaned sows and two boars were randomly assigned to five groups as T1, T2, T3, T4 and T5 each consisting of six. Pigs T1 and T3 groups were bred at the body weight of 70-8...