Meat Science Commons^™

Prenatal Transportation Stress Did Not Impact Ovarian Follicle Count For Three Generations Of Female Brahman Offspring, Lacey K. Quail, Ronald D. Randel, Thomas H. Welsh Jr., Robert A. Cushman, Hannah K. Yake, Rui A. D'Orey Branco, Donald A. Neuendorff, Charles R. Long, George A. Perry

Roman L. Hruska U.S. Meat Animal Research Center: Reports

As prenatal transportation stress altered behavior and adrenal glucocorticoid secretion of calves, we hypothesized that prenatal transportation stress would decrease ovarian reserve size and negatively impact female offspring fertility. The impact of prenatal transportation stress on ovarian follicle numbers in female offspring for three generations was studied. Brahman cows were transported for 2 h on day 60 ± 5, 80 ± 5, 100 ± 5, 120 ± 5, and 140 ± 5 of gestation. Ovaries were collected from offspring of transported or non-transported dams at multiple ages. Primordial, primary, secondary, and antral follicles were histologically analyzed. Antral follicle numbers were …

Comparison Of Performance Of F1 Romanov Crossbred Ewes With Wool And Hair Breeds During Fall Lambing And Body Weight And Longevity Through Six Production Years, Thomas W. Murphy, Brad A. Freking

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The objective of this study was to evaluate wool (Dorset and Rambouillet) and hair (Dorper, Katahdin, and White Dorper) breeds for their ability to complement Romanov germplasm in an annual fall lambing system by estimating direct maternal grandsire and sire breed effects on economically important lamb and ewe traits. After 3 yr of evaluation under spring lambing, ewes of the five F1 types were transitioned to spring mating, exposed to composite terminal sires, and evaluated under a barn lambing system at 4, 5, and 6 yr of age. A total of 527 first generation crossbred (F1) ewes produced 1,151 litters …

The Effect Of Varicocele On Semen Quality In Boars Exposed To Heat Stress, Tasha R. Gruhot, Brett White, Benny Mote

Department of Animal Science: Faculty Publications

Semen quality has a dramatic impact on reproductive efficiency in the swine industry, influencing both conception rate and litter size. The objective of this study was to assess whether the presence of varicocele hinders semen quality in both thermoneutral and heat stress (HS) conditions. At approximately 6 mo of age, ultrasonography was used to measure left and right pampiniform plexus area in order to detect varicocele in maternal line boars at the University of Nebraska–Lincoln. Between 10 and 12 mo of age, semen was collected from each boar (n = 28) twice weekly. Boars were collected under thermoneutral conditions, were …

Antral Follicular Count Is A Tool That May Allow The Selection Of More Precocious Bradford Heifers At Weaning, R. Santa Cruz, R. A. Cushman, C. Viñoles

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Although antral follicle count is a repeatable parameter across life that is positively associated with fertility, its use at weaning as a tool to discard less fertile heifers has not been extensively evaluated. The hypotheses of this work are: 1) maximum antral follicle count (MAFC) is repeatable between weaning and pre breeding evaluations, allowing selection of more fertile heifers at an early age, 2) heifers with high MAFC have growth and development parameters linked to an earlier puberty and pregnancy, 3) MAFC has a positive correlation with AMH concentrations, so that both could be used inter changeably. In this study, …

Triennial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved, Deb L. Hamernik, Andrea S. Cupp, John S. Davis

Department of Animal Science: Faculty Publications

In honor of the 50th anniversary of the Society for the Study of Reproduction (SSR), a Triennial Reproduction Symposium was cosponsored by SSR and the American Society of Animal Science (ASAS). The Society for the Study of Reproduction was formed in 1967 when a group of reproductive biologists that were members of ASAS met with physician scientists and decided to organize a new scientific society. The goal of SSR was to promote the study of reproduction by fostering interdisciplinary communication among scientists, holding conferences, and publishing meritorious studies. Today after its 50th anniversary, the mission for SSR is to harness …

Evaluation Of Reduced Subsets Of Single Nucleotide Polymorphisms For The Prediction Of Age At Puberty In Sows, Katherine L. Lucot, Matthew L. Spangler, Melanie D. Trenhaile, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Genomic information could be used efficiently to improve traits that are expensive to measure, sex limited or expressed late in life. This study analyzed the phenotypic variation explained by major SNPs and windows for age at puberty in gilts, an indicator of reproductive longevity. A genome-wide association study using 56,424 SNPs explained 25.2% of the phenotypic variation in age at puberty in a training set (n = 820). All SNPs from the top 10% of 1-Mb windows explained 33.5% of the phenotypic variance compared to 47.1% explained by the most informative markers (n = 261). In an evaluation population, consisting …

Ewe Fertility In The Star Accelerated Lambing System, R. M. Lewis, D. R. Notter, D. E. Hogue, B. H. Magee

Department of Animal Science: Faculty Publications

Effects of environmental factors such as ewe age, season of exposure, and time from lambing to exposure on fertility were evaluated using records on 1,084 Dorset ewes in the STAR accelerated lambing system. The STAR program consisted of five 30-d concurrent breeding and lambing periods per year beginning on January 1, March 15, May 27, August 8, and October 20. Fertility in the flock changed in a cyclic and predictable fashion during the year. Changes in prolificacy were less consistent but also tended to show cyclic variation. Matings that occurred within the typical breeding season (August, October, and January) were …

Evaluation Of Holstein Bull Sperm Quality By Flow Cytometry, B.E. Ballachey, L.K. Jost, D.P. Evenson

South Dakota Beef Report, 1986

Frozen semen samples from Holstein bulls were measured by the sperm chromatin structure assay (SCSA), a new procedure utilizing flow cytometry for the valuation of sperm quality. Fertility ratings of the bulls were known based on their use in artificial insemination matings. Values obtained by the SCSA were highly correlated (r= -.58 P<.01 with bull fertility ratings. Results of this research indicate the SCSA may be a valuable technique for measurement of sperm cell quality and detection of suboptimal fertility in bulls.

Cattle Fertility Not Harmed By Pour-On Insecticides, D J. Barker

Journal of the Department of Agriculture, Western Australia, Series 4

Pour-on insecticides have been a feature of lice and fly control on cattle for many years and in many countries, but it seems that only in Western Australia have they been suspected of lowering fertility.

Frequent reports of this effect have been received by the Department of Agriculture since the first pour-on insecticide was marketed in W.A. in the late 1960's, culminating in the research work reported below.

The work clears pour-ons as a cause of reduced fertility in herds.