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M. L. FAHNING, R. H. SCHULTZ and E. F. GRAHAM

Summary.

Uterine fluid and blood serum samples were collected from 100 adult dairy cows during various stages of the oestrous cycle and analysed for their free amino acid content. A total of twenty-five free amino acids and amino compounds were identified in uterine fluids while only twenty-three were identified in blood serum. The concentration of the total and of most of the individual free amino acids was greater in uterine fluid than in blood serum at all stages of the oestrous cycle. The total content of free amino acids and the concentration of several individual free amino acids in uterine fluids showed cyclical variations. The significance of free amino acids in uterine fluids is discussed.

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R. H. SCHULTZ, M. L. FAHNING and E. F. GRAHAM

Summary.

Chemical analyses were conducted on uterine fluid and blood serum collected from eighty-eight normal adult dairy cows during various days of the oestrous cycle. Uterine fluid contained higher concentrations of reducing substances, potassium, inorganic phosphate and alkaline and acid phosphatase activity than blood serum while levels of calcium and sodium were higher in blood serum than in uterine fluid, supporting the concept that bovine uterine fluid is a product of active secretion and not of simple diffusion from the blood. Concentrations of reducing substances, total protein, potassium, chloride, inorganic phosphate and alkaline and acid phosphatase activity in bovine uterine fluid were all found to vary with the stage of the oestrous cycle, indicating that, in the case of these substances at least, secretion into the uterine lumen is under hormonal control. The level of alkaline phosphatase in the blood serum was also found to vary with the stage of the oestrous cycle.

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Kim H Brown, Irvin R Schultz and James J Nagler

Exposure of fishes to environmental estrogens is known to affect sexual development and spawning, but little information exists regarding effects on gametes. This study evaluated embryonic survival of offspring from male rainbow trout (Oncorhynchus mykiss) exposed to 17α-ethynylestradiol (EE2) using an in vitro fertilization protocol. Males were exposed at either 1800 or 6700 degree days (°d) (i.e. 161 or 587 days post-fertilization (dpf)) to test for effects on testes linked to reproductive ontogeny. At 1800°d, fish were beginning testicular differentiation and were exposed to 109 ng EE2/l for 21 days. At 6700° d, fish have testes containing spermatocytes and spermatids and were exposed for 56 days to either 0.8, 8.3, or 65 ng EE2/l. Semen was collected at full sexual maturity in each group and used to fertilize eggs pooled from several non-exposed females. Significant decreases in embryonic survival were observed only with the 6700°d exposure. In 0.8 and 8.3 ng EE2/l treatments, embryo survival was significantly reduced at 19 dpf when compared with the control. In contrast, an immediate decrease in embryonic survival at 0.5 dpf was observed in the 65 ng EE2/l treatment. Blood samples collected at spawning from 6700° d exposed males revealed a significant decrease in 11-ketotestosterone and a significant increase in luteinizing hormone levels for the 65 ng EE2/l treatment when compared with the other treatment groups. Results indicate that sexually maturing male rainbow trout are susceptible to EE2 exposure with these fish exhibiting two possible mechanisms of reduced embryonic survival through sperm varying dependant on EE2 exposure concentrations experienced.

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L. F. ARCHBALD, R. H. SCHULTZ, M. L. FAHNING, H. J. KURTZ and R. ZEMJANIS

Summary.

The histological appearance of the cells of the rete ovarii in heifers suggests that this ovarian structure could be secretory in nature. A holocrine type of secretion appears to be involved and is restricted to the dioestrous phase of the oestrous cycle.

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L. F. ARCHBALD, R. H. SCHULTZ, M. L. FAHNING, H. J. KURTZ and R. ZEMJANIS

Eighteen pregnant cows were individually housed and allowed to calve normally. None of the cows retained fetal membranes. Tissues were obtained for study on Days 1, 3, 5, 7, 11, 15, 19, 23, 27, 31, 45 and 60 post partum. Because the exact time of calving of each animal was not known, the term `Day 1' represented an approximated period of 24 hr beginning from the time of observation of the calf with its dam in the maternity stall.

Following exposure of the internal genitalia as described by Schultz, Fahning & Graham (1966), caruncular and intercaruncular uterine samples were obtained from an area at the base of the uterine horn by an in-vivo serial surgical technique (Archbald, 1969). Uterine

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M. L. FAHNING, R. H. SCHULTZ, E. F. GRAHAM, J. D. DONKER and H. W. MOHRENWEISER

Since the introduction of 6α-methyl-17α-acetoxyprogesterone (map or medroxy-progesterone acetate) many trials and research projects have been conducted using this orally active progestin. Considerable variation in conception rate following synchronization of oestrus with this compound has been reported (Hansel, 1965; Zimbelman, 1965). The objective of the current study was to evaluate the effect of a specific dosage of map (RepromixR, The Upjohn Company, Michigan) on fertility when administered under specifically controlled conditions.

Forty Holstein heifers, 15 to 18 months of age, were used in this study. These animals, as part of another experiment, were being fed two different types of hay (Hay types A and B) with twenty animals assigned to each group. Ten animals were selected from each group to be recycled while the remaining ten animals from each served as

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R. H. SCHULTZ, H. B. BURCALOW, M. L. FAHNING, E. F. GRAHAM and A. F. WEBER

Height measurements of surface and glandular epithelium, cell to nucleus length ratios and glandular lumen sizes have been employed for evaluating the endometrial activity of the uterus in the cow (Asdell, DeAlba & Roberts, 1948; Dziuk, Donker, Nichols & Peterson, 1958; Foley & Reece, 1948; Weeth & Herman, 1952; Johnson, 1965). These techniques, however, have not been completely satisfactory. For example, epithelial height measurements were reported to vary greatly in areas of tissue closely adjacent to one another (Dziuk et al., 1958). Johnson (1965) found that epithelial height varied between and within periods of the oestrous cycle to such an extent that this measurement was not valid for estimating the stage of the cycle. Hultquist (1959) described a technique of karyometry used on β-cells of the
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A. G. HUNTER, W. L. JOHNSON, L. D. S. BARKER, M. L. FAHNING and R. H. SCHULTZ

Summary.

The seminal vesicle of the bat (Myotis lucifugus) contained a protein toxic to mice and rabbits but not to bats. This protein was precipitated with ammonium sulphate, non-dialysable, inactivated by papain and relatively heat stable. The lethal action was caused by hypotension due to a general relaxant effect on smooth muscle. Epinephrine only momentarily elevated blood pressure. The toxin had no effect on electrical transmission along the motor-nerve axon and across the neuromuscular junction. Haematocrit values increased significantly after bat seminal vesicle was injected, while a highly significant (P> 0·01) decrease in the proportion of circulating lymphocytes and a highly significant (P>0·01) increase in proportion of circulating heterophils occurred. Isolated mouse duodenum and uterine preparations showed a diminution in contraction frequency and a decrease in muscle tone in the presence of the toxin. This was reversible by washing the toxin from the system.

The hypothesis was proposed that this seminal vesicle protein enters the female bat during copulation, blocks sperm transport, and alters the phagocytic system, thus allowing bat spermatozoa to remain in the female reproductive tract over an extended period of time.

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A. G. HUNTER, L. D. S. BARKER, W. L. JOHNSON, M. L. FAHNING and R. H. SCHULTZ

Summary.

The antigenicity of male bat reproductive organs was studied using agar-gel diffusion. Four precipitin lines formed with testis and anti-testis, six lines with epididymis and anti-epididymis, and six lines with ampulla and anti-ampulla sera. Tissue extracts of liver, spleen, heart and uterus cross-reacted with the three antisera to produce three lines. Ampulla, epididymis and testis possessed at least one, three and one organ-specific antigens, respectively.

Nine proteins were detected in the seminal vesicles by agar-gel electrophoresis. One of these possessed potent toxic properties when injected into rabbits and mice. The toxic protein was isolated by zonal electrophoresis and by chromatography on Sephadex G-200. It migrated electrophoretically as a pre-albumin, had a molecular weight of approximately 44,600 and an LD50 value of 162μg/kg. The relationship between this protein and the unique phenomenon of bat sperm survival is unknown.

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P. L. Kaye, G. A. Schultz, M. H. Johnson, Hester P. M. Pratt and R. B. Church

Summary. Between the 1-cell zygote and the early blastocyst stage of mouse embryos the net rate of uptake of methionine increased, the internal pool became progressively more expanded and less easily reached steady state, and the specificity of competitor amino acids changed. Sodium-dependent transport was first detected in compacted morulae (16–32-cell stage). Uptake of [14C]methylaminoisobutyric acid was detectable in blastocysts but not in unfertilized eggs. Efflux of methionine by an exchange transport system was detectable at all stages, but in intact blastocysts much higher external concentrations were required to activate exchange transport. An exchange system with properties similar to that operating at cleavage stages was exposed when blastocysts were collapsed with cytochalasin D. Since this exchange system was not detectable in isolated inner cell masses, it may be confined to the juxtacoelic surface of trophectoderm cells.