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Item Ancestral Breed Grouping for Improving Animal Modeling in Admixed Populations and Its Use in Leptin (Genetic and Hormone) Association Studies with Performance Traits in Commercial Beef Cow Herd(North Dakota State University, 2021) Bhowmik, NayanThe first study investigated American Aberdeen (AD) cattle's genetic structure and its genetic relationships with five American taurine beef breeds and the genetic population structure of a related admixed cattle herd for improved statistical modeling. The last two studies investigated the role of leptin (LEP) c.73C>T polymorphism, leptin diplotype (LEPD), and leptin hormone (LEPH) concentration on reproductive, growth, size, feeding, and carcass ultrasound traits in beef cows and heifers. High levels of polymorphism were observed in admixed, Red Angus, and Gelbvieh (GV) populations. The lowest level of polymorphism was found in AD followed by undetermined parentage. Pairwise fixation index displayed the largest genetic differentiation between AD and GV, Simmental, and Shorthorn breeds. Even though founder animals originated from the Angus breed, the AD breed exhibited unique genomic characteristics. Mixed animal models with or without pedigree that included the primary ancestral breed group (ABG) for admixed individuals developed from diversity analyses performed better than models without the ABG. With these improved models, novel relationships between LEP genotype and number of follicles and ovary size were identified. Similar relationships of the LEP genotype in multiple growth and weight traits that have been published before have been confirmed. However, reverse relationships were observed for feed efficiency. The LEPD showed associations for feed efficiency, weight traits, and body size traits. Novel relationships between LEPH categories (high vs. low) were reported on two feeding behavior traits, including number of meals per day and feed intake per meal. However, no relationship was observed between LEP genotype and plasma LEPH concentration in this population. Literature indicates the increased productivity of the T allele for growth and carcass attributes, so it was expected that the same increased productivity would be found for reproductive traits. Therefore, the T allele of LEP c.73C>T marker could be used as a valuable marker for selecting for improved growth, body size, and reproductive performance in commercial beef heifers. Also, circulatory LEPH before the breeding season may serve as a predictor for feeding behavior, body size, and reproductive traits. Even so, not all comparisons could be statistically proven; therefore, additional investigations may be warranted.Item An Evaluation of Feeding Hempseed Cake in Finishing Cattle Diets(North Dakota State University, 2022) Winders, ThomasUnderstanding the potential of hempseed cake to be used as a livestock feedstuff is important for both industrial hemp and beef producers. Experiment 1 evaluated the effects of hempseed cake (HEMP) on growth performance, feeding behavior, plasma metabolite concentrations across time, and carcass characteristics when fed in finishing diets to heifers in comparison to dried corn distillers grains plus solubles (DDGS). Experiment 2 investigated the effects of HEMP on diet ruminal fermentation parameters, total tract digestibility, nutrient flow, and nitrogen balance in finishing steers in comparison to DDGS and a control (CON) diet containing no byproduct. Experiment 3 explored the effects of hempseed cake on immune parameters in response to an endotoxin (lipopolysaccharide) challenge in finishing steers in comparison to DDGS and CON. In experiment 1, the HEMP diet reduced heifer growth performance and hot carcass weight while not influencing dry matter intake, feeding behavior, or other carcass characteristics. Plasma urea nitrogen (PUN) was greater for heifers fed the HEMP diet, and glucose and total amino acid concentrations were not influence by treatment. In experiment 2, ruminal ammonia and total VFA concentrations were greatest for steers fed the HEMP diet. Furthermore, organic matter (OM) intake tended to be greater, OM total tract apparent digestibility was reduced, and N digestibility was greatest for steers fed the HEMP diet, and site of digestion was influenced by treatment. Nitrogen retention was greatest in steers fed the HEMP diet, suggesting treatment influence on N metabolism. In experiment 3, there was a treatment by hour interaction for PUN, and plasma glucose and NEFA were not influenced by treatment. Plasma IL-1α, IL-36RA, and TNF-α were lowest in steers fed the HEMP diet, and all other cytokines and total amino acid plasma concentrations were not influenced by treatment. Hempseed cake negatively influences growth performance in large part because of reduced total tract apparent OM digestibility, while N total tract apparent digestibility and N retention are improved and immune response is influenced, so further understanding of these outcomes is needed to explore implications of feeding hempseed cake to finishing cattle.Item Factors Affecting Testicular Growth and Development in the Beef Bull(North Dakota State University, 2019) Negrin-Pereira, NicolásAt present no single parameter can predict potential daily sperm production (DSP) in bulls. Sertoli cells (SC) are responsible for nourishing and providing physical support to germ cells (GC) throughout spermatogenesis. The size of the SC population established before puberty is one of the major factors determining DSP in the bull. Fine needle aspiration (FNA) is a technique used for diagnostic purposes in many species but its application to determine the size of the SC population remains unexplored. Our objectives were to compare two stains (immunohistochemistry vs. conventional HE) and three techniques to determine SC density in neonatal and prepubertal bulls [22G FNA (SMEAR), 14G needle with vacuum (CORE) and tissue section (HIS)], and the effects of three different interventions on testicular growth, development and cytology in neonates, pre and peripubertal bulls: corn supplementation during mid to late gestation of dams, the age of the dam and the administration of vitamin A. The significant correlation observed between GC and SC counts in neonatal and prepubertal bulls, highlighted the relationship between both cell populations established in the early gonad. Although no significant correlation existed between techniques for SC density, the significant relationship established between SC counts and GATA4+ cell density implies the process can be automated. Corn supplementation to multiparous dams during mid to late gestation did not have any effect on testicular gross parameters and cytology in neonatal bulls coincident with the lack of differences in fetal growth between treatments. No significant differences in scrotal circumference, testicular weight or cytology existed between prepubertal bulls from primiparous heifers or adult multiparous cows. Nevertheless, bulls from heifers had lower bodyweights at 194 days of age compared with bulls from cows. The administration of vitamin A to peripubertal bulls had no effect on scrotal circumference, testicular weight or cytology. Nevertheless, epididymis in treated bulls were significantly heavier than non-treated animals. The data generated in the present experiments highlights the need for more research to generate new interventions aiming to influence the size of the SC population in the testis and the potential daily sperm production in the beef bull.Item The Effects of Red Meat or Sugar Supplementation during Gestation and Lactation on Maternal Reproduction, Maternal and Offspring Blood Parameters, and Offspring Body Composition(North Dakota State University, 2019) Siomka, Alexis MichelleUsing swine as a model for humans, this study was conducted to examine whether maternal consumption of added protein (red meat) or free sugar (glucose) throughout gestation and lactation was associated with maternal reproduction, maternal and offspring blood parameters, and offspring mature body composition. Maternal breed of sows of at least one year of age at breeding were utilized. At D-40 of gestation, sows were randomly assigned to one of four dietary supplementation treatments 1) Control (CON): corn-soy gestation diet; 2) Beef (GB): 4 oz cooked beef patty; 3) Sugar (SUG): sugar on a caloric equivalent to the beef patty; 4) Half sugar and half beef (SB): a supplementation of a beef and sugar mixture. Fewest piglets farrowed per litter was seen in the CON sows when compared to GB, SUG or SB treatments (P<0.04), with no difference in total number farrowed between GB, SUG, and SB sows (P>0.6). Although GB sows had piglets with a lower average birth weight than CON sows (P=0.02) and no difference in average piglet growth during lactation (P=0.17) or in weaning weight (P=0.08). There were no (P>0.05) differences in traits measured in the sow (subcutaneous backfat depth, body weight, and energy balance). No treatment effect was seen in low-density lipoprotein (LDLch) (P=0.31); however, serum LDLch continued to decrease for SUG sows from early to late gestation. There were differences for high-density-lipoproteins (HDLch) with GB sows having the greatest HDLch levels when compared to CON and SUG during mid gestation (P=0.05 and 0.004, respectively). There were treatment differences seen during mid- and late gestation with GB sows having higher total cholesterol (TOTch) than SUG and CON sows (P<0.05). During mid gestation, TOTch was higher for GB than SB (P=0.006), resulting in lower TOTch for SB during late gestation (P=0.08). It can be concluded that the supplement provided during gestation and lactation, had a minimal effect on overall maternal reproduction, maternal and offspring blood parameters, and on mature body composition of offspring. Positive outcomes for offspring and mothers cannot be expected if the supplementation is not needed.Item Understanding the Equine Distal Limb(North Dakota State University, 2019) Gunkelman, MattiaStudies examining health of the distal limb and lameness conditions are important for education and future research. It is hypothesized that changes to the external hoof would result in alterations to blood flow throughout the distal limb and changes to digital cushion thickness. To investigate these things, the following experiments (exp) were conducted. Exp 1: MRI images of the equine distal limb. All images had identified abnormalities to internal structures, and a lameness score assigned. Digital cushion thickness was measured, however no relationship of thickness and lameness was observed (P≥0.12). Exp 2: Trimming and shoeing is a routine procedure for maintenance of proper hoof health; therefore two exp at separate locations (NDSU and UMC) were conducted to examine digital cushion thickness, carpal joint circumference, and blood flow during this time. Specifically, measurements were obtained 24h post trimming and shoeing and periodically throughout an 8 wk period. No significant differences were identified in carpal joint circumference or digital cushion thickness at either location. Thermographic images identified changes in hoof temperature in bare and shod horses at both locations. Week by treatment interaction was significant at NDSU (P=0.04), with hoof temperature decreased in both treatment groups one week post trimming and shoeing. Shod horses remained below baseline throughout the 8 week period, and were significantly colder (P=0.02) than bare at 8 wk. Week by treatment interaction was also significant at UMC (P<0.0001), with decreased hoof temperature in both treatment groups 4 wks post trimming and shoeing, followed by shod horses increasing to baseline at 8 wk while bare remained colder. Exp 3: Transformative learning in undergraduate students. Undergraduate students enrolled in an Equine Science research course conducted four individual studies. Transformative learning was assessed throughout the course through reflection questions and discussions. It was determined that transformative learning was achieved, however it was dependent on the particular student and their previous experience and knowledge. Overall, the current experiments provide further understanding of the distal limb. Further research should continue to place focus on those structures and mechanisms within the hoof which play an overall role in its proper function.Item Effects of Replacing Supplemental Sucrose with Beef During Mid to Late Gestation on Maternal Health and Fetal Growth and Development Using a Sow Biomedical Model(North Dakota State University, 2019) Nelson, Megan AliceAmericans consume three percent more total daily calories from sugar than current recommendations. Maternal diets high in sugar can cause obesity and diabetes mellitus. Objectives were to compare supplemental dietary sucrose to a protein alternative on maternal health and fetal programming utilizing a sow biomedical model. Pregnant sows (Landrace × Yorkshire, average BW = 222 ± 35 kg, n = 21) were fed a corn-soybean meal-based diet (CSM) at one percent BW at 0700 h daily from d 29 (± 1.47) to 111 (± 0.58) of gestation. Sows were randomly assigned to dietary supplement treatments: 126 g CSM (CON, n = 5), 110 g cooked ground beef (BEEF, n = 6), 85.5 g sucrose (SUCR, n = 5), or the combination of 54.8 g BEEF and 42.7 g SUCR (B+S, n = 5). Dietary supplements were fed three times daily from d 40 to 110 (± 0.58) of gestation. A repeated measures design was modeled using the MIXED procedure of SAS. Dietary treatment did not influence gestational BW (P ≥ 0.99), subcutaneous fat depth (P ≥ 0.09), blood chemistry panel (P ≥ 0.21), or total-, HDL-, or LDL-cholesterol, triglyceride, insulin, or C-reactive protein serum concentrations (P ≥ 0.07). Dietary treatment did not influence sow organ or lean tissue weight (P ≥ 0.42). Compared to CON, BEEF fetuses had increased BW (P = 0.01), crown to rump length (P = 0.01), nose to crown length (P < 0.01), heart girth (P = 0.02), and abdominal girth (P = 0.05). Dietary treatment did not influence fetal growth characteristics of median weight male and female fetuses (P ≥ 0.23). Compared to BEEF, SUCR fetuses had heavier liver weights (P = 0.04). Dietary treatment by sex interaction occurred for fetal kidney weight with BEEF males having heavier kidney weights compared BEEF females (P = 0.03). Dietary treatment did not influence other fetal organ or lean tissue weights (P ≥ 0.09). These results suggest beef or sucrose supplementation at 1.49 or 1.16 grams per kilogram BW per day, respectively, from day 40 to 110 of gestation had minimal impact on maternal health and fetal development.Item Energy and Mineral Supplementation Strategies for Beef Cattle Grazing the Northern Great Plains(North Dakota State University, 2019) McCarthy, Kacie LynnFour experiments were conducted to evaluate different technologies and supplementation strategies that may impact beef cattle production in the Northern Great Plains. Our overarching hypothesis was that we can enhance beef cattle performance and production through strategic supplementation of energy and minerals. In experiment 1, steers were fitted with transmission beacons on collars to determine effects of preweaning creep feeder attendance influences on post-weaning performance, feeding behavior, and carcass characteristics. Calves that visited creep feeders more frequently spent more time eating and ate more meals during the first 28 d of the finishing period. In experiment 2, we utilized electronic feeders to monitor mineral intake of cow-calf pairs and found that HIGH (>90 g/d; average 125.4 g/d) intake cows and calves spent more time at the mineral feeder than their LOW (<90 g/d; average 33.5 g/d) intake counterparts. Furthermore, we noted greater concentrations of Se, Cu, and Co in livers of HIGH intake cows compared to LOW intake cows. In experiment 3, we evaluated a slow-release vitamin and mineral bolus in feedlot heifers which failed to influence heifer performance, liver mineral concentrations or carcass characteristics. Overall, heifers performed as expected while on a finishing diet from feeds sourced in the Northern Great Plains. In experiment 4, we further utilized the SmartFeed system to control intake of individual heifers assigned to different treatments in a group pasture scenario. Our results clearly show that the feed controlling portion can be used for precision feeding of individuals in extensive group managed scenarios. Though heifers had similar BW and ADG among treatment groups, treatments that provided supplemental mineral enhanced liver concentrations of Se, Fe, Cu, and Co. Furthermore, the CowManager system was able to detect divergence in highly active behavior among treatment groups, but also reported many false health and estrus-related alerts. Overall, we were able to successfully monitor individual mineral intakes in cow-calf pairs and report differences in energy and mineral supplement intakes in heifers grazing native range. We were also able to corroborate differences in supplement intakes with changes in concentrations of mineral in the liver of animals.Item Effects of Nutrient Restriction, Realimentation, and Twinning on Plasma Volume, Umbilical Hemodynamics and Placental Characteristics in the Pregnant Adolescent Ewe(North Dakota State University, 2019) Vasquez Hidalgo, Manuel AlexanderReproductive physiology in production animals is a key economic component of longevity and profitability of animal farming. There are several components that can benefit or compromise adequate pregnancy periods. Sheep production is not only a very important economic activity for farmers around the United States, but sheep are also an important medical and surgical model to study human diseases. Our findings suggest that estradiol-17 beta could be involved in acute increased plasma volume early in gestation which can benefit overall gestation. We report that umbilical blood flow decreases upon nutrient restriction in adolescent ewes and does not recover upon realimentation. Finally, we suggest that a similar umbilical blood flow, placental development and plasma volume expansion in twins and singleton pregnancies could be enough to obtain similar birthweights in singletons and twins.Item Reproductive and Nutritional Impacts of Dried Distiller's Grains with Solubles on Growing Rams and Feedlot Lambs(North Dakota State University, 2017) Crane, Alison RyanByproduct supplementation in livestock rations is viable and can lead to increased returns to producers. Increasing the inclusion of dried distiller’s grains with solubles (DDGS) was hypothesized to increase growth performance in feedlot and growing ram lambs, while negatively affecting reproductive characteristics of ram lambs. Ethanol production in the United States provides an affordable byproduct feed for livestock, in the form of DDGS. Due to its RUP and energy content, DDGS can be readily incorporated into ruminant diets, with S concentration being the main concern for livestock health. The impacts of DDGS on feedlot lamb performance were evaluated on 240 crossbred (Suffolk × Rambouillet) lambs in a completely randomized design with a 3 x 2 factorial arrangement of treatments. Lambs were placed into 24 feedlot pens (4 pens/treatment) for a 111 d finishing study. Treatments included increasing concentration of DDGS (0, 15, or 30% DM basis) and inclusion of LAS (0 or 22.05 g/metric ton LAS) resulting in treatments of: 1) 0% DDGS without LAS (0DDGS-NL), 2) 0% DDGS with LAS (0DDGS-L), 3) 15% DDGS without LAS (15DDGS-NL), 4) 15% DDGS with LAS (15DDGS-L), 5) 30% DDGS without LAS (30DDGS-NL), and 6) 30% DDGS with LAS (30DDGS-L). The inclusion of LAS increased (P ≤ 0.02) final BW, ADG, G:F, and HCW. To evaluate the effects of DDGS on growth performance and reproductive traits in ram lambs, 112 Suffolk and Hampshire ram lambs were allocated to four treatments (n = 4 pens/treatment) in a completely random design. Basal diets were 60% corn, 25% oats, and 15% commercial market lamb pellet (CON). Treatments were (% DM basis): 15% of the ration as DDGS substituted for corn (15DDGS), 30% of the ration as DDGS substituted for corn (30DDGS) and 45% of the ration as DDGS substituted for corn (45DDGS). Rams were fed to d 112 on their respective treatment (PHASE 1), after which rams were placed on the CON ration until d 168 (PHASE 2). Many growth traits exhibited positive quadratic or cubic effects (P ≤ 0.05), indicating a possibility of both DDGS and LAS being viable supplements for sheep in growing rations.Item Perceptions of Modern Meat-Animal Production from Consumers Two to Three Generations Removed from the Farm(North Dakota State University, 2019) Reed, DeMetris Deon, Jr.A consumer is defined as a person who purchases goods and services for personal use or a person or thing that eats or uses something (Merriam-Webster, 2019). Consumers either want or need to eat meat, whether it is for self-gratification or nutritive purposes. The modern consumer definition of “meat” has changed from the original hunter stalking prey to now contemporary livestock production practices that confine and feed sophisticated diets in an effort to achieve outstanding muscle-food quality. Those who produce and supply consumers with food and fiber must achieve a higher level of education in keeping with technological advances. Further, there is a change in the demographics of modern farmers/ranchers, with more women entering the field (Lucier, 2019). Younger generations are technologically savvy and seek “finger-tip” evaluation access of the meat they are considering for purchase. These consumers demand instant access to industry trends in order to keep current with the next meat branding idea (ex. Guaranteed Tender and Flavorful Beef). Consumers are no longer waiting for the producer and product to come to them, they are seeking out local and reliable agricultural products suppliers in their hometown. This “buy local” idea is pushing a food trend in restaurants and food service to provide menu options consisting of locally grown and prepared items (Mealey, 2019). Innovative development of technology that provides instant access to information regarding the places that offer these food products as well as information regarding the product quality is giving consumers purchasing power. The following research will examine the aspects of consumer perception of meat production relative to modern consumers that are two to three generations removed for the farm.
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