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E. S. E. HAFEZ

Summary.

Rabbit ova were transferred to both sides of synchronous pseudopregnant recipients; on one side the ova were transferred to the ovarian bursa to assess the efficiency of ovum reception, and on the other side were deposited within the Fallopian tube to provide information on ovum transport. The recipients were treated with oestrogens, progesterone, or combinations of these hormones. Ova were also transferred to control untreated animals, and to those in which superovulation had been induced. Recipients were autopsied 4 days post coitum, and the ova recovered and examined.

Oestrogen treatment did not influence ovum reception, progesterone produced a slight improvement, and a combination of oestradiol and progesterone gave a greater improvement. Retention of ova in the Fallopian tube was induced by oestrogen treatment, and this effect was opposed when progesterone was given also. Survival rate of blastocysts was reduced by oestrogen treatment especially when ova were retained within the tube. Retained ova had thicker mucin coats. Fewest ova were lost from the reproductive tract in oestrogen-treated animals. Factors affecting rate of pre-implantation embryonic growth are discussed.

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E. S. E. HAFEZ

Summary.

The survival of fertilized ova in gelled media in vitro was studied with the ovum transfer technique. A total of 1507 selected healthy ova of two to four or eight to thirty-two blastomeres was stored at 10° C in gelled media containing 7 %, 5 % and 1 % of gelatine in 1 : 1 serum : saline-solution for 4, 24, 48, 72, 120 and 144 hr. After storage, the ova were transferred to the Fallopian tubes of 115 recipient rabbits in a synchronous stage of pseudopregnancy. As controls, ova were stored for similar periods in liquid media of 1 : 1 serum : saline-solution mixture and ova were also transferred without storage. The recipients were laparotomized at 8 days post coitum (p.c.) to record implantations and were killed 15 days p.c. to count surviving embryos.

After storage for 4 hr in 7 % gelatine, the implantation rate of morulae was 72%. The percentage gradually declined until it reached 31% after 144 hr of storage. Implantation rate for ova stored in 7 % gelatine was slightly but consistently higher than for ova stored in liquid media for the corresponding periods. However, the difference was not statistically significant. Medium containing 1 % gelatine was superior to 5 % and similar to 7 % concentration.

Two- to 4-blastomere ova survived in gelled and liquid media from 4 to 48 hr at rates comparable with those of eight to thirty-two blastomeres. Storage in gelled media was superior to that in liquid media. After 72 hr of storage, the implantation rates of 2- to 4-blastomere ova in both gelled and liquid media were much lower than those of eight to thirty-two blastomeres.

Survival rate of morulae in gelled media was not improved in the presence of carbon dioxide. Slow warming after storage at low temperature was harmful to ovum survival. Serum was indispensable for ovum survival in gelled media. Embryo survival was the same for ova stored in gelled or liquid media. Embryonic survival of implantations from ova previously stored for 144 hr was significantly lower than that of ova stored for 4 to 72 hr. The use of autologous or heterologous serum did not change rates of implantation or embryo survival. The major morphological changes in the ova during storage were coarse granulation, loss of spheroid shape, lack of distinct blastomeres and the presence of a marked depression. The results are discussed in relation to physiological integrity of the ovum and functional defects occurring before or after implantation. The practical significance of the finding is discussed in relation to ovum transfer techniques in large animals.

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E. S. E. HAFEZ

Scanning electron microscopy (SEM) has been used to study the morphology of mammalian spermatozoa (Dott, 1969; Fujita, Miyoshi & Tokunaga, 1970; Luse, 1970; Zaneveld, Gould, Humphreys & Williams, 1971), ova (Gould, Zaneveld, Humphreys & Williams, 1971) and cilia (Barber & Boyde, 1968), as well as tissue organization of uterine epithelium during delayed implantation (Psychoyos & Mandon, 1971) and cervical neoplasia (Jordan & Williams, 1971). The purpose of this study was to observe the morphology and tissue organization of ciliated and secretory epithelium in the female reproductive tract.

The reproductive tracts of four adult female crab-eating macaque, Macaca fascicularis, and six adult female New Zealand rabbits were dissected 3 hr post coitum, with or without fixation in vivo with 2% glutaraldehyde (Reinius & Nilsson, 1969). Tissue specimens were pinned

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E. S. E. HAFEZ

Summary.

A total of 180 nulliparous rabbits was bred, bilaterally ovariectomized 2 or 4 days post coitum, and injected daily with 0·5, 0·75, 1, 4 or 40 mg of progesterone alone or in combination with oestradiol at a ratio of 1 : 400 or 1 : 4000. Uninjected, unilaterally and subtotally ovariectomized rabbits and progesterone-treated intact animals served as controls. The animals were autopsied at 6 days post coitum and 1111 blastocysts were recovered, examined for their normality and their diameters measured. The length and weight of uterus were affected neither by ovariectomy nor by the dose of injected progesterone. Intact does had an average of 6·6 to 9·0 viable blastocysts and 0·3 to 0·6 degenerating blastocysts. Ovariectomized does had an average of 4·1 to 10·2 viable blastocysts and 0 to 2·2 degenerating blastocysts. In ovariectomized does the percentage of viable blastocysts, the size of blastocysts and diameter of embryonic disc were decreased when the daily dose of progesterone was less than 1 mg and when oestradiol was combined with progesterone at a ratio of 1 : 400. There was no quantitative relationship between dosage of progesterone on one hand and percentage of viable blastocysts, size of blastocysts and diameter of embryonic disc on the other hand. Salpingectomy, unilateral ovariectomy, subtotal ovariectomy or administration of progesterone in intact rabbits had no significant effect on viability and size of blastocyst or diameter of embryonic disc.

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E. S. E. HAFEZ and E. RAJAKOSKI

Summary.

Nulliparous, multiparous and post-partum rabbits were mated following treatment with luteinizing hormone or superovulation injections. A total of 1009 blastocysts was recovered 144 hr post coitum and they were measured microscopically. Ovulation rate tended to increase with increase in parity. Superovulatory response was not lower in post-partum animals. The number of degenerating blastocysts per doe increased in all superovulated groups. The percentage of viable blastocysts among the total number of recovered blastocysts did not vary in ovulated groups and in one superovulated group. A high percentage of oversized blastocysts was recorded in a superovulated group with a good response to gonadotrophins. Many undersized blastocysts were recorded for superovulated does with a poor response to gonadotrophins. Blastocyst size tended to decrease in does with a poor superovulatory response. The diameter of the embryonic disc following superovulation was smaller than in ovulated groups. There was interlitter and intralitter variation in the microscopical appearance of the embryonic disc. In pooled data the outer diameter of the blastocyst was not significantly correlated with the diameter of the embryonic disc. The position of the blastocysts in utero was not correlated with the diameter of the blastocyst or the diameter of the embryonic disc.

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G. E. KODITUWAKKU and E. S. E. HAFEZ

In the rabbit, blastocyst size varies greatly from one doe to another, and is not apparently related to such factors as the weight of the dam and sire or the age of the dam (Beatty, 1958), and the parity of the female (Hafez & Rajakoski, 1964). On the other hand, lactation and stress cause a reduction in the size of the blastocyst and the diameter of the embryonic disc (Hafez & Ishibashi, 1965), and blastocyst diameter is directly related to the racial size of the parents (Castle & Gregory, 1929). The present investigation was undertaken to evaluate the variation in blastocyst size between two breeds of rabbits of different body size. Twenty-three New Zealand White (adult body weight 3·2 to 4·2 kg) and thirty-three Dutch-Belted (adult body weight
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E. S. E. HAFEZ and I. G. WHITE

Summary.

The activity of alkaline phosphatase, acid phosphatase, glutamic-oxalacetic transaminase (got), lactic dehydrogenase (ldh), amylase, succinic dehydrogenase (sdh) and glucose-6-phosphate dehydrogenase (gph) has been determined in the intercaruncular and caruncular areas of the endometrium during the follicular and luteal phases of the oestrous cycle and from 13 to 35 days of pregnancy in the ewe.

The activities of the enzymes in the two areas of the endometrium were similar except that alkaline phosphatase activity was higher, and sdh lower, in the intercaruncular area.

During the luteal phase of the oestrous cycle and during early pregnancy, alkaline and acid phosphatase activities increased in the intercaruncular and caruncular areas. Amylase and got values were also elevated in the caruncular area during early pregnancy. The level of ldh in the intercaruncular area of the endometrium was less during the luteal phase than during the follicular phase of the oestrous cycle.

Enzyme activity was variable in the chorion, embryo and blastocoelic fluid. The only statistically significant change was a sharp rise in the acid phosphatase concentration of the blastocoelic fluid at 31 to 35 days of pregnancy.

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I. AREF and E. S. E. HAFEZ

The phasic activities of utero-oviducal musculature are co-ordinated to accomplish successful gamete transport. In untreated rabbits, the oviducal musculature shows dramatic daily changes in contractility (Salomy & Harper, 1971). In oestrogen-treated rabbits, contractions are characterized by high frequency, small amplitude and irregular pattern (Mattos & Coutinho, 1971). This oestrogen-dominated pattern is observed with either high or moderate doses of the steroid (Greenwald, 1963). During the luteal phase, the oviducal musculature becomes increasingly active (Boling, 1971) in response to increasing progestagen concentrations. Maximal contractility of the myometrium occurs during the preovulatory phase, and a `myometrial block' (Csapo, 1970) is established during the luteal phase.

A chronological study of the characteristic motility patterns may provide a further understanding of their physiological implications. The purpose of this investigation was to study cyclical changes in

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K. HAMANA and E. S. E. HAFEZ

Specific proteins exist in the uterine fluid of the rabbit, but not in the maternal blood serum. These have been named `blastokinin' Krishnan & Daniel, 1967) and `uteroglobin' (Beier, 1968a). It appears on the basis of their physiochemical properties that blastokinin and uteroglobin may be identical. Blastokinin appears in uterine fluid at 3 days post coitum (p.c.) and reaches maximal concentrations at 5 days p.c., disappearing by the 9th day. It also occurs in blastocoelic fluid at 6 days p.c. (Beier, 1968b). The purpose of this investigation was to study the ontogeny of uteroglobin and serum proteins in the blastocoelic fluid of the rabbit in relation to implantation. Adult, nulliparous, New Zealand white rabbits were mated twice with two fertile bucks and injected intravenously with 20 i.u. human chorionic gonadotrophin immediately
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M. R. JAINUDEEN and E. S. E. HAFEZ

Summary.

The effects of androgens on differentiation of embryonic ovaries during early pregnancy in the cow have been studied. Androgens injected between the allantochorion and the endometrium of cows (37 to 80 days pregnant) did not transform the gonads of female foetuses in the male direction but were capable of masculinizing the external genitalia of bovine female foetuses.