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Biomedical subjects

J W Macpherson

Publications and source records attributed to J W Macpherson.

At least 19 recordsLinked to original sources
PubMed1982

Survival of preimplantation embryos in the uteri of mice induced to superovulate and subsequently ovariectomized.

The effect of ovariectomy-induced hormonal deprivation for 3, 5, 7 or 9 days on the capacity of the mouse uterus to maintain large numbers of blastocysts was studied. Both the percentage of pregnant females and the number of embryos per female decreased from 90% with 18.89 embryos per female after 3 days to 40%, with 4.63 embryos per female, after 9 days of hormonal deprivation. The capacity of embryos from superovulating donors to implant in pseudopregnant recipients was unimpaired during the first 5 days of hormonal deprivation but was significantly impaired after 7 days.

Animals↗
PubMed1977

The effect of caproic acid, handling technique and storage times on the fertility of fowl spermatozoa.

The effects of three levels of caproic acid in glycine-citrate extender on preservation of fertilizing capacity of fowl spermatozoa were tested. Extended semen stored for 6 and 28 hours was used for insemination in diluted or reconcentrated forms. The results indicated that semen stored in the extender with the highest concentration of caproic acid provided superior fertility and showed the importance of proper handling of hens during insemination.

Animals↗
PubMed1976

In vitro development of secondary blastodiscs from dispersed blastoderm cells of Gallus domesticus.

A study of the in vitro growth of embryonic structures from dispersed blastoderm cells is reported. The specific type of blastoderm cells with the capability of growing on the coverslip developed into the discoidal embryonic structures resembling those of avian species. The glass surface was apparently an initiator of differentiation into at least three types of cells specifically distributed in the blastodisc. Groups of structures formed were evaluated at 6, 12, 24 and 36 hours to study the developmental pattern in vitro and to estimate the number of cells per structure. Microscopic examination of the area pellucida revealed that all three basic germ layers were established after 24 hours of incubation in vitro. The 36 hour stage was represented by bulky growth of mesodermal-like cells and changes in hypoblast layer where some of the cells degenerated and some were transformed to mesenchymal spindle-like cells.

Animals↗
PubMed1969

Frozen turkey semen.

Semen samples from Bronze turkeys, extended with Brown's buffer and antibiotics, and protected with combinations of ethylene glycol-glycerol and N,N-dimethylacetamide-glycerol were frozen at the rate of 8 degrees C per minute down to -196 degrees C. Similar treatments were used as controls. Five White virgin hens were inseminated with semen from each group before and after dialysis. The per cent fertility of the frozen semen samples after dialysis was lower than the corresponding control groups.

Animals↗
PubMed1968

The reproductive tract of the turkey hen (a biometrical study).

A biometrical study of the reproductive tracts of 173 hens was carried out after slaughter at 53 weeks of age. Mean weights and total lengths of the reproductive tracts of four strains of actively laying turkey hens were 265 - 279.5 grams and 80.9 - 84.5 centimetres. Mean measurements in centimetres of oviduct anatomical divisions were: infundibulum 10.9 - 11.7, magnum 44.5 - 45.2, isthmus 12.6 - 14.5, uterus 9.6 - 10.8, and vagina 2.6 - 3.5.

Animals↗
PubMed1968

The effect of season on testicular weight and spermatogenesis in turkeys.

Semen collection was carried out on Large White and Auburn turkeys over a nine month period beginning in February. Equal numbers of each strain were slaughtered periodically throughout the summer and fall. The testicles were recovered, weights recorded, and histological sections were prepared and examined for signs of active spermatogenesis. Significant differences occurred in the testes weight between the two strains studied in the May and September tested birds. Significant differences also occurred in the testes weight within strains between the males slaughtered in May and October. Microscopic examination of histological sections revealed a progressive reduction in active spermatogenesis between testes recovered in early summer and those recovered in the fall.

Animals↗
PubMed1967

Boar semen studies. II. Laboratory and fertility results of a method for deep freezing.

A successful method for low temperature preservation of bull semen was modified for use with boar semen and resulted in recovery of twenty to fifty per cent motile cells immediately after thawing. Recovered cells did not survive five hours incubation at 37 degrees C. and no pregnancies resulted following insemination of twenty-four sows and gilts with frozen semen.

Animals↗
PubMed1967

Animal identification. I. Liquid nitrogen branding of cattle.

A number of branding tools of various metals and various sizes in combination with several wetting agents were cooled with liquid nitrogen and applied for different lengths of time to calves and mature cattle. White hair appeared in the shape of the brand on the animals in place of dark hair when the application was properly carried out. Best results can be obtained by using metal irons at least 25 millimeters thick and 14 millimeters wide with xylol as a wetting agent for ten seconds in young or thin skinned animals and up to twenty seconds in mature or thick skinned animals.

Animals↗
PubMed1966

The reproductive tract of the porcine female. (A biometrical study).

A biometrical study of female porcine reproductive tracts recovered after slaughter was carried out. Sizes and weights of the various areas from one hundred eighty-seven sow tracts, eighty-one pre-puberal gilts and thirty-two puberal gilts were recorded. A table of abnormalities observed in examination of the sow tracts is also presented.

Animals↗