Reproductive and Urinary Physiology Commons^™

The Effects Of Lactation And Negative Energy Balance On Kisspeptin-Stimulated Luteinizing Hormone And Growth Hormone In Dairy Cows, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin

Brian K Whitlock, PhD, DVM, DACT

Kisspeptin, a neuroendocrine regulator of gonadotropin releasing hormone, is hypothesized to integrate nutrition and hormones critical to metabolism and the regulation of reproduction. Since the negative energy balance of early lactation is associated with reduced fertility via suppression of gonadotropin secretion and enhanced growth hormone (GH) responsiveness, this experiment was designed to determine the effects of stage of lactation and negative energy balance on kisspeptin-10 (Kp-10) stimulated luteinizing hormone (LH) and GH concentrations. Five nonlactating [5.1 ± 0.8 (SEM) years; 577 ± 19 kg body weight (BW)] and five lactating [4.1 ± 0.6 years; 608 ± 11 kg BW] multiparous …

The Effects Of Lactation And Negative Energy Balance On Kisspeptin-Stimulated Luteinizing Hormone And Growth Hormone In Dairy Cows, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin

Animal Science Publications and Other Works

Kisspeptin, a neuroendocrine regulator of gonadotropin releasing hormone, is hypothesized to integrate nutrition and hormones critical to metabolism and the regulation of reproduction. Since the negative energy balance of early lactation is associated with reduced fertility via suppression of gonadotropin secretion and enhanced growth hormone (GH) responsiveness, this experiment was designed to determine the effects of stage of lactation and negative energy balance on kisspeptin-10 (Kp-10) stimulated luteinizing hormone (LH) and GH concentrations. Five nonlactating [5.1 ± 0.8 (SEM) years; 577 ± 19 kg body weight (BW)] and five lactating [4.1 ± 0.6 years; 608 ± 11 kg BW] multiparous …

An In Vitro Model Of Ovarian Cancer: Studying The Effects Of Talc And Pycnogenol®, Amber Renée Buz'zard

Loma Linda University Electronic Theses, Dissertations & Projects

Ovarian cancer is the sixth most common cancer and accounts for more deaths than any other cancer of the female reproductive system. The American Cancer Society has suggested that poor diet, talc and industrial pollutants may increase the risk of developing ovarian cancer. Talc is ubiquitous and concern is raised about its safety, role as a possible carcinogen and known ability to cause irritation and inflammation. Due to the silent nature of ovarian cancer, chemoprevention is a high priority. The most useful chemopreventive compounds will inhibit, delay or reverse carcinogenesis, and can be taken for long periods of time with …

Gene Expression In The Mouse Placenta: Developmental And Stress Responses, Ciprian P. Gheorghe

Loma Linda University Electronic Theses, Dissertations & Projects

Successful placental development is crucial for optimal growth, maturation, and survival of the embryo/fetus. Placental failure and placental pathology contributes to both morbidity and mortality of the fetus. We sought to understand normal placental development and also placental responses to stress using oligonucleotide microarray technology. To examine genetic aspects of normal placental development, we investigated gene expression patterns in the murine placenta at embryonic day 10.5 (E10.5), E12.5, E15.5, and E17.5. Hypoxia has been identified as a major stressor in placental and fetal development. In order to comprehend more completely hypoxic stress responses we sought to measure gene expression changes …

The Effect Of Antioxidant Supplementation On Human Sperm Cryopreservation, Katrina E. Taylor

Theses : Honours

Semen cryopreservation has an important role in assisted reproductive technology however, the cooling, freezing and thawing processes often result in a significant loss of sperm motility, viability and nuclear integrity. The destructive effects of cryopreservation are significantly exacerbated in samples exhibiting low sperm number and poor morphological characteristics. Recent research into infertility has focused on the correlation between excessive oxidation and subfertility, in particular radical induced lipid peroxidation within the phospholipid bilayer of the spermatozoon plasma membrane and the promotion of cellular damage as a result of antioxidant insufficiency. The aim of this study was to evaluate the effect of …

The Benefits Of Breastfeeding: An Introduction For Health Educators, Sheila G. J. Clark, Timothy J. Bungum

Environmental & Occupational Health Faculty Publications

Currently 16% of Americans breastfeed their children for at least 12 months as recommended by the AAP, which is well below the HP 2010 goal of 25%. Breastfed infants receive benefits that can improve their health throughout their lives. The benefits of breastfeeding for children include increased resistance to infectious diseases, such as gastroenteritis, respiratory tract infections, and ear infections. Breastfed children also display lower rates of chronic diseases including diabetes, obesity, asthma, and leukemia. The choice to breastfeed results in economic benefits from lower health care costs and from reduced spending on infant formula. The Healthy People 2010 targets …

Short Communication: Relationship Between Body Growth And Mammary Development In Dairy Heifers, L F. Silva, M J. Vandehaar, Brian K. Whitlock, R P. Radcliff, H A. Tucker

Brian K Whitlock, PhD, DVM, DACT

Our objective was to determine if prepubertal rate of body weight (BW) gain, independent of diet, was related to mammary development of dairy heifers. Data from two studies recently conducted at Michigan State University were used to identify factors, within a dietary treatment group, that would account for variation in first lactation milk production or amount of mammary parenchymal DNA at the time of puberty. Factors analyzed for variation in milk production during first lactation were: postpartum BW, prepubertal BW gain, gestational BW gain, postpartum BW gain, body condition score (BCS) at breeding, and BCS at calving. Factors analyzed for …

Short Communication: Relationship Between Body Growth And Mammary Development In Dairy Heifers, L F. Silva, M J. Vandehaar, Brian K. Whitlock, R P. Radcliff, H A. Tucker

Faculty Publications and Other Works -- Large Animal Clinical Sciences

Our objective was to determine if prepubertal rate of body weight (BW) gain, independent of diet, was related to mammary development of dairy heifers. Data from two studies recently conducted at Michigan State University were used to identify factors, within a dietary treatment group, that would account for variation in first lactation milk production or amount of mammary parenchymal DNA at the time of puberty. Factors analyzed for variation in milk production during first lactation were: postpartum BW, prepubertal BW gain, gestational BW gain, postpartum BW gain, body condition score (BCS) at breeding, and BCS at calving. Factors analyzed for …

Histological Evaluation Of Cryopreserved Ovaries In Autologous Abdominal Transplant To NaïVe, Outbred, Cd1, Mice, Wentia Elissa Ford

Biological Sciences Theses & Dissertations

This study showed that fresh and frozen-thawed mouse ovaries would maintain viable primordial or primary follicles post-autologous transplantation. Furthermore, with appropriate hormonal stimulation, these early-stage follicles were shown to develop into Graafian follicles containing a metaphase II antral ovum. Partially sliced ovaries were transplanted into the abdominal cavity of naive, outbred, CD1, white mice. Hormonal stimulation with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) one week after the autologous transplantation stimulated variable degrees of follicle and ovum maturation within the ovarian tissue. There were no major morphological differences observed between the four groups, three treatment and one …

Effect Of Dietary Protein On Prepubertal Mammary Development In Rapidly Growing Dairy Heifers, Brian K. Whitlock, M J. Vandehaar, L F. Silva, H A. Tucker

Brian K Whitlock, PhD, DVM, DACT

The objective was to determine whether increased dietary protein would enhance mammary development in prepubertal heifers fed for rapid body growth (1.2 kg/d). Fifty-four Holstein heifers (weighing approximately 134 kg) were assigned to one of three treatments. Heifers were fed a total mixed ration with metabolizable energy at 2.85 Mcal/kg and metabolizable protein at low, standard, or high concentrations (37, 41, or 44 g/Mcal of metabolizable energy, respectively) from 3.5 mo of age until slaughter at approximately 46 d after puberty. Heifers fed low, standard, and high protein gained 1130, 1170, and 1180 g/d, respectively. Dietary protein did not affect …

Effect Of Dietary Protein On Prepubertal Mammary Development In Rapidly Growing Dairy Heifers, Brian K. Whitlock, M J. Vandehaar, L F. Silva, H A. Tucker

Faculty Publications and Other Works -- Large Animal Clinical Sciences

The objective was to determine whether increased dietary protein would enhance mammary development in prepubertal heifers fed for rapid body growth (1.2 kg/d). Fifty-four Holstein heifers (weighing approximately 134 kg) were assigned to one of three treatments. Heifers were fed a total mixed ration with metabolizable energy at 2.85 Mcal/kg and metabolizable protein at low, standard, or high concentrations (37, 41, or 44 g/Mcal of metabolizable energy, respectively) from 3.5 mo of age until slaughter at approximately 46 d after puberty. Heifers fed low, standard, and high protein gained 1130, 1170, and 1180 g/d, respectively. Dietary protein did not affect …

Characterization Of Host-Bacteria Interactions Contributing To Group B Streptococcus Colonization, Jennifer Marie Smith

Theses, Dissertations and Capstones

Group B streptococcus (GBS) is the leading cause of life-threatening bacterial infections during the first three months of life. GBS is also a frequent cause of maternal postpartum infections. Both types of infections stem from maternal vaginal and/or rectal colonization with GBS in the perinatal period. Limited information is available concerning how the colonization process occurs and what role the host immune system may play in the establishment of persistent colonization by GBS. The complex interactions between the immune system and GBS normally should end in clearance of the bacteria. However, since colonization by GBS occurs in a large number …

Map Kinases In Cynomolgus Monkey Sperm Hyperactivation, Emily Nicole Haynes

Biological Sciences Theses & Dissertations

Mammalian sperm exhibit characteristic motility patterns, termed hyperactivated (HA) motility, associated with completion of capacitation. In cynomolgus monkey (Macaca fascicularis) sperm, this HA motility is dependent in vitro upon the addition of exogenous cyclic nucleotide mediators, caffeine and dibutyryl-cyclic adenosine monophosphate (dbcAMP). Previous reports have shown protein tyrosine phosphorylation to be an integral component of this caffeine- and cAMP-stimulated HA motility. This study investigated the involvement of the mitogen-activated protein (MAP) kinase-signaling cascade. Semen specimens were collected in Talp-HEPES medium from proven breeders via electroejaculation. After washing, sperm were incubated in the presence and absence of the MAP …

Age Related Changes In Contractile Sensitivity To Cyclic Gmp And Intracellular Calcium Compartmentalization In Ovine Arteries, Surya Margono Nauli

Loma Linda University Electronic Theses, Dissertations & Projects

The study examines the hypothesis that maturation changes the ability of cGMP to produce cerebral vasodilatation and alters the relative intracellular calcium pool sizes in ovine arteries. In ovine basilars taken from near-term fetal and young adult sheep, 8- pCPT-cGMP relaxed potassium- and serotonin-induced tone with pD2 values of 4.4±0.1 and 4.9±0.1 (fetal basilar) and 4.0±0.1 and 4.7±0.1 (adult basilar), respectively. In fura-2 loaded arteries, 8-pCPT-cGMP significantly lowered increases in cytosolic calcium concentration induced by serotonin but not potassium regardless of age. When calcium sensitivity was calculated in the same arteries as the slope of the relation between calcium concentration …

Catecholamines And The Regulation Of Uterine Contractions In The Pregnant Rhesus Macaque, Cahleen Mae Mcnutt

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to test the hypothesis that: 1) maternal and/or amniotic fluid catecholamines or prostaglandins display nocturnal activity rhythms similar to those of the myometrial contractility in the pregnant rhesus macaque and, 2) catecholamines stimulate prostaglandin production by fetal membranes. Paired maternal arterial blood and amniotic fluid samples were collected at 0900 h (AM) and 2100 h (PM) from chronically catheterized rhesus macaques until delivery and analyzed for prostaglandin metabolites (PGFM and PGEM-II) and catecholamines (norepinephrine, epinephrine, and dopamine). Uterine activity data was continuously recorded. A rhythm in uterine contractility was observed, with peak activity between 1900 and …

Progesterone And 17 Α-Hydroxyprogesterone: Novel Stimulators Of Calcium Influx In Human Sperm, Peter F. Blackmore, Stephen J. Beebe, Douglas R. Danforth, Nancy Alexander

Bioelectrics Publications

Progesterone and 17 alpha-hydroxyprogesterone (but not other steroids such as testosterone, corticosterone, beta-estradiol, estrone, dehydroepiandrosterone, 20 alpha-hydroxypregnen-3-one, androstenedione, and pregnenolone) were shown to cause an immediate increase, in free cytosolic calcium ([Ca2+]i) in both capacitated and noncapacitated human sperm, using the fluorescent indicator fura 2. Significant increases in [Ca2+]i were observed with 10 ng/ml progesterone, while maximum effects were seen with 1 microgram/ml progesterone. Two other steroids 11 beta-hydroxyprogesterone and 5 alpha-pregnane-3,20-dione exhibited significant activity to increase [Ca2+]i. This increase in [Ca2+]i elicited by progesterone was entirely due to Ca2+ influx from the extracellular medium since the increase in [Ca2+]i …

Production From Heifers And First Calvers, G J. Sawyer

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

Heifers and first calvers present the major problems of the beef breeding herd. Reproduction rates, calf growth and survival of first calvers are generally much poorer than those of adult breeders.

Early successful reproductive performance is important in beef herds because of the high overhead cost of keeping breeding beef heifers or cows, Where possible, beef producers should aim to join heifers at 14 to 15 months of age. To achieve this goal, producers should set production targets for those animals. These targets will differ from farm to farm depending on when calves are turned off and the seasonal feed …

The Effects Of 712-Dimethylbenz (A) Anthracene On Ovarian Steroidogenesis And Uterine Growth In The Mouse, Jeffrey Lynn Clark

Biological Sciences Theses & Dissertations

It has been previously demonstrated that 7,12-dimethylbenz(a) anthracene (DMBA) is an initiator of ovarian granulosa cell tumors. It is also known that DMBA leads to destruction of primordial oocytes, and that tumor induction may involve the interaction of pituitary gonadotropins. However, the effects of DMBA on ovarian steroidogenesis and uterine growth in relation to the tumorigenic process have not been investigated. Therefore, the present study was conducted to examine these parameters using adult C57Bl/6N mice treated in proestrus and diestrus II with 0.1 ml corn oil with or without 1.5 mg DMBA and killed 44 hours later. The uteri and …