Life Sciences Commons^™

Atrazine Influence On Northern Pike Sperm Motility And Viability In Minnesota, Andy Stevens, Paul Pallardy

Journal of Undergraduate Research at Minnesota State University, Mankato

Concern has been noted by fish hatchery biologists with the Department of Natural Resources that southern Minnesota northern pike Esox lucius populations have exhibited reduced hatching rates, a trend not occurring with northern Minnesota pike populations. The chemical atrazine is a frequently used herbicide in Minnesota and has been found to cause gonadal dysgenesis and reproductive development issues in amphibians and fish. Sperm, length, and age data were collected from northern pike in four Minnesota lakes. Water samples were obtained from two of the lakes to test for atrazine. Test results indicated atrazine concentrations0.10 and r2 < 0.06 for all regressions). Sperm motility reductions in northern pike could be related to declining populations and warrants further research.

Influence Of Steroids And Gonadotropins On Reproduction In Beef Cattle, Thomas L. Devine

Graduate Theses and Dissertations

The objective of this thesis was to evaluate the influence of steroids and gonadotropins on reproduction in beef cattle. In experiment 1, beef heifers were used to determine the influence of growth-promoting implants on growth, reproductive development, estrous behavior, and pregnancy rate. Heifers were assigned to 1 of 4 implant treatment groups: control (CON); trenbolone acetate (TBA); trenbolone acetate plus estradiol (TBA+E2) or zeranol (ZER). Heifers were implanted once, A.I. and exposed to bull during this experiment. Body weight, BCS, HH, RTS, estrous behavior and pregnancy data were collected throughout this experiment. Average daily gain of heifers was greater for …

Effects Of Pubertal Status And Number Of Estrous Cycles Prior To Breeding In Beef Heifers, Average Daily Gain On Reproductive Performance And Comparison Of Two Fixed Time Ai Estrus Synchronization Protocols, Rebecca Vraspir

Department of Animal Science: Dissertations, Theses, and Student Research

Reproductive success is the most important factor in beef cattle production and is affected by timing of pubertal onset in heifers, and reproductive biotechnologies utilized. Three studies were conducted to evaluate the effects of pubertal status, ADG, and 2 fixed time AI protocols on reproductive success in beef heifers.

In the first study, heifers that were pubertal prior to breeding had a greater AI and overall pregnancy rate; produced more calves born within the first 21 d of the calving season; and weaned older, heavier calves than non-pubertal heifers. Additionally, heifers that had ≥2 estrous cycles, prior to the first …

Reproduction And Nesting In Teleost Fish, With A Focus On Reproduction In Centrarchids And Specific Analysis Of Nesting In Lepomis Megalotis, Rebecca Irene Allee

Undergraduate Honors Thesis Collection

Fish represent the most diverse and oldest living class of vertebrates, making up approximately 48% of all known members of the subphylum Vertebrata (Bolis, et al. 2001). They are able to live in a wide variety of habitats, from salt water to fresh water and from cold polar seas to areas of intense pressure in the depths of the ocean (Moyle and Cech 1996). Because of this overwhelming diversity, the evolution and ecology of fishes has been a dynamic field of study (Moyle and Cech 1996). Researchers have generally divided fish into three distinct groups: jawless fishes (Class Agnatha), …

Life History Tradeoffs And The Costs Of Reproduction In Arizona Bark Scorpions (Centruroides Sculpturatus), Michael Marie Webber

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tradeoffs in life history evolution result from conflicts in the time and energy that can be simultaneously invested in activities such as growth, reproduction, and survival. Reproduction is an energetically costly activity for organisms, and is known to elicit alterations in the daily activity patterns of individuals. I investigated reproductive tradeoffs in the Arizona Bark Scorpion,Centruroides sculpturatus. To better understand the nature of tradeoffs in this species, I examined the influence of reproductive state on the predatory efficiency and thermal preference of reproductive females. Further, I examined the influence of reproductive activities (i.e. gestation) on the ability of reproductive females …

Methods Of Bovine Reproduction, Kelsey L. O'Donnell

Honors Scholar Theses

The beef and dairy cattle industries are of immense economic value in the United States and have made impressive advancements over the past century. Their success depends strongly upon the reproductive efficiency of their breeding programs. This overview discusses the major advancements in bovine reproduction that have been integrated into the beef and dairy cattle industries and also the emerging technologies that are currently being researched. Current practices like artificial insemination and estrus synchronization resulted from the development of a strong understanding of cattle physiology and the endocrinology of the estrous cycle. With these technologies, selection of superior genetic traits …

Fear Effects On Pheasant Reproductive Ecology And A Curriculum To Teach Wildlife Habitat Selection, Jessica Laskowski

School of Natural Resources: Dissertations, Theses, and Student Research

Predation risk is an important source of selection that shapes prey density, distribution and abundance. The immediate impacts of predator consumption on prey populations are widespread and well-studied, and a growing body of research demonstrates immediate impacts of predator-induced fear (independent of prey mortality) on prey behavior, physiology and life-history expression. However, predation risk is often seasonally variable and while it is clear that consumption effects often carry over to influence prey population demography for years after predators have disappeared, the temporal carry-over effects of fear on prey populations remain largely unexplored. We assessed effects of fall hunting activity by …

Evaluación De Parámetros Productivos Y Reproductivos En La Bufalera El Marañón En La Dorada En El Departamento De Caldas, Juan Kamel Dumar Ayala, Juan David Romero Ortiz

Zootecnia

Este trabajo se hizo con el propósito de evaluar los parámetros productivos y reproductivos en la bufalera El marañón, en La Dorada en el departamento de Caldas. La evaluación se hizo tomando registros históricos (n= 3189 datos), comprendidos en un periodo de 9 años. Los parámetros evaluados fueron: Peso al nacer (PN), Peso al destete (PD), Peso a los 18 meses (P18), Ganancia de peso diaria pre (GPPRE) y pos destete (GPPOST), Edad al primer parto (EPP), Intervalo entre partos (IEP), se les aplico un análisis por medio de estadística descriptiva. Los resultados de promedios y desviación estándar para los …

Age, Growth, And Reproductive Biology Of Atlantic Bonito (Sarda Sarda Bloch, 1793] From The Turkish Coasts Of The Black Sea And The Sea Of Marmara, Abdullah Ekrem Kahraman, Di̇dem Göktürk, Taner Yildiz, Uğur Uzer

Turkish Journal of Zoology

This study aims to investigate some biological characteristics of Atlantic bonito, Sarda sarda Bloch, 1793, from the Turkish coasts of the Black Sea and the Sea of Marmara. A total of 212 S. sarda (100 females, 89 males, and 23 undetermined) were sampled monthly between May 2011 and September 2012. The sex ratio (male/female) was 0.89; females prevailed but not statistically significantly so. Fork lengths of all sampled individuals ranged from 17.7 to 63.0 cm. The length-weight relationship for all individuals was calculated as W = 0.01 L^{3.085}. The ages of the fish ranged from 0+ to 2+. Growth parameters …

Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, José Lino Costa, Maria José Costa, Cynthia Jones

OES Faculty Publications

Reproductive stage determination of male gonads has received sparse attention in fish biology literature with few studies detailing the building of gross anatomical- and histologic scales. The meagre (Argyrosomus regius) is one of the world's largest sciaenids and supports a significant regional fishery in European and North African waters whose reproductive patterns are yet to be fully investigated. In the present study, we derive a macroscopic grading system for meagre testis using semi-quantitative graphs that feature the testis variability along the species size range and time of the year. We then describe the histological stages and reproductive phases of male …

In Vivo Embryo Production In Some Native Goat Breeds In Turkey, Ali̇ Reha Ağaoğlu, Kübra Karakaş, Mustafa Kaymaz

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to assess the efficacy of the repeated administration of superovulatory protocol and surgical procedure in in vivo embryo production, as well as to determine the differences in the responses to superovulatory treatment among several Turkish native goat breeds (Angora, Kilis, Honamli, Hair, and Norduz). A superovulatory treatment procedure was repeated 3 times in this study. The estrus cycles were synchronized and superovulatory response was induced with porcine follicle-stimulating hormone during the natural breeding season. Natural mating was performed following CIDR removal. Embryo recovery was performed surgically on day 6, after the first mating. According …