Search Results

You are looking at 1 - 5 of 5 items for

  • Author: K. JANAKIRAMAN x
Clear All Modify Search
Free access

K. JANAKIRAMAN and L. E. CASIDA

Summary.

Sixty-eight oestrous New Zealand white rabbits were used in four experiments to study the pituitary lh content, ovulation time and corpus luteum development in the presence of intra-uterine devices (IUD) fitted in both horns. The results indicate that the IUD-fitted animals ovulate later and their pituitary lh content following mating is higher than in sham-operated controls. Also, such animals have lighter and less luteinized corpora lutea compared with their sham-operated controls at 24 hr after mating.

Free access

K. JANAKIRAMAN, K. P. SHUKLA, B. A. GADGIL and N. C. BUCH

Studies on the mechanism of action on intra-uterine foreign bodies are gaining importance in the field of reproductive biology. Doyle & Margolis (1963, 1964a, b) found in the rat that, following ovulation and fertilization, implantation did not occur in the threaded uterine horn due to a hostile uterine environment and interference with the normal decidual reaction. Buch, Shukla & Hawk (1964) showed that in the Surti water buffalo an intra-uterine polyethylene loop prevented ovulation. In cows, Hawk, Conley, Brinsfield & Righter (1964) observed that the loop acted as a contraceptive device within 3 days of breeding, possibly by interfering with one or more of the following processes: fertilization, cleavage, ovum transport and corpus luteum formation. The action of ovarian hormones on the histology of the uterus following ovariectomy has
Free access

O. J. GINTHER, C. O. WOODY, S. MAHAJAN, K. JANAKIRAMAN and L. E. CASIDA

Summary.

The effect of oxytocin administration on the oestrous cycle was studied in sixteen uterine-intact and thirty-two surgically prepared unicornual heifers. Unilateral hysterectomy was performed on Day 3 of the oestrous cycle and oxytocin or an equivalent volume of physiological saline was administered daily from Day 3 to Day 7 or 8. Oxytocin produced significantly shorter oestrous cycles in the intact heifers and in the unicornual heifers with the retained uterine horn adjacent to the cl, but not in the unicornual heifers with the retained horn opposite to the cl. These results strongly suggest that at least part of the effect of oxytocin is exerted through local, utero-ovarian channels. A unilateral effect of the uterus on the cl was demonstrated in unicornual heifers that did not receive oxytocin. The oestrous cycles were extended and the cl persisted when the retained horn was opposite to the cl, but not when the retained horn was adjacent to the cl.

Free access

O. J. GINTHER, C. O. WOODY, K. JANAKIRAMAN and L. E. CASIDA

Summary.

A plastic coil was inserted surgically on Day 3 of an oestrous cycle into one uterine horn of each of ten heifers. Sham-operations were performed on five additional heifers. The oestrous cycles in which the cl was on the operative side were significantly shorter than the cycles in which the cl was on the non-operative side or the cycles of the sham-operated controls. The average cycle length when the cl was on the non-operative side was not significantly different from the cycle length of the sham-operated controls. These results indicate that a plastic coil in the cranial portion of one uterine horn of the heifer results in a unilateral `inhibitory' influence on the cl.

Free access

K. JANAKIRAMAN, C. O. WOODY, S. P. AGARWAL, R. C. BHALLA, K. P. SHUKLA, B. A. GADGIL, N. C. BUCH and L. E. CASIDA

Summary.

The effects of IUDs on the occurrence of ovulation and the pituitary gonadotrophin content was studied in water buffalo heifers of the Surti breed. Thirty-six of these heifers were divided into four equal groups. Group 1 received sham operations, while Groups 2, 3 and 4 were fitted with plastic IUDs in the cranial region of the uterus either ipsilaterally or contralaterally (in relation to the side on which ovulation occurred) or bilaterally, 72 hr after the exhibition of heat. Treated heifers showed significantly shorter cycles than the controls (P<0·01). There was no difference between Groups 2, 3 and 4. Heifers were slaughtered after the onset of heat in post-IUD-insertion cycles. Eight of the nine heifers ovulated in the control group, but only three in the group fitted with bilateral IUDs and one each in the groups fitted with ipsilateral and contralateral IUDs. The other ovarian characters studied did not show any significant differences among the four groups.

The anterior pituitaries from these heifers in different groups were freeze-dried and assayed for lh and fsh. Neither lh nor fsh activity was statistically different among treatment groups.

The results of this experiment suggested that an IUD, when present in one horn, also affects the adjacent ovary of the opposite horn to induce shorter cycles. This contralateral effect may be mediated systemically either at the level of the pituitary, the hypothalamus, or both. It is not possible to rule out transmission of a uterine factor from the IUD-horn to the non-IUD horn.