Overfeeding of phosphorus (P) is a contributing factor to P levels in surface waters. The objective of this study was to determine the impact of increasing levels of corn gluten feed (CGF) as a supplemental source of P on fecal P excretions. Eight Hereford steers (427±79 kg) were randomly assigned to one of four dietary treatments in a 4 x 4 replicated Latin square design. Steers were fed chopped grass hay ad libitum (0.13% P) and 0, 0.5, 1.0 or 1.5 kg/d of dried CGF pellets. All steers were supplemented with 0.91 kg/d beet pulp, 0.34 kg/d rumen-inert fat supplement and 18.14 g/d trace mineral salt. Urea was added to the respective diets at levels of 95.25, 72.57, 49.90, and 31.75 g/d to ensure equal dietary protein across treatments. Steers were housed individually and fitted with total fecal collection bags. Steers were adjusted to each diet for 9-d followed by a 5-d collection period. Following the final collection of each period, a 10 ml jugular blood sample was collected and analyzed to determine serum inorganic P. Dietary total P increased (P < 0.05) as CGF level increased: 8.72, 12.59, 16.75 and 20.88 g/d. Dry matter digestibility increased linearly (P < 0.05) as dietary P increased: 50.35, 53.66, 54.25 and 55.42%. Total P excretion increased linearly (P < 0.05) with increasing CGF level: 9.66, 11.71, 14.29, 16.96 g/day. Inorganic P excretion increased linearly (P < 0.05) with increasing CGF level: 4.11, 5.93, 8.36 and 9.92 g/day. Total P excretion was highly related (P < 0.05; r2 = 0.79) to inorganic P excretion. Serum inorganic P increased linearly (P < 0.05) with increasing dietary P content: 5.61, 5.87, 6.64 and 6.80 mg/dL. Fecal P increased as CGF level increased in steers fed varying dietary levels of P from plant sources. Management of P intake can be a strategic practice to reduce P fecal excretions in beef cattle. / Master of Science

Lipid oxidation degrades the quality and decreases the shelf-stability of muscle foods. The depletion of phosphates prior to cooking may be a major factor in this undesirable reaction. Thus, the effects on lipid oxidation with the use of an encapsulate to protect the phosphates during raw storage was investigated. Unencapsulated and encapsulated sodium tripolyphosphate (STP) and sodium acid pyrophosphate (SAPP), at a level of 0.5%, were compared to control samples in cooked, ground beef patties at 0 and 6 days. The unencapsulated and encapsulated treated samples were different (P<0.05) from the controls with an 81.1% to 89.7% improvement in the reduction of lipid oxidation. However, encapsulated phosphates did not decrease the level of oxidation beyond the unencapsulated treatment. This observation was attributable to the lack of a storage time prior to evaluating rancidity. Therefore, with an increase of precooked storage time, the 0.10% active encapsulated STP was essentially as effective as 0.20% unencapsulated STP for both 3 and 11 days. Unencapsulated STP (0.3% or 0.5%), encapsulated STP (0.3% or 0.5% active), a blend of unencapsulated (0.3%) and encapsulated (0.2% active) STP, and a control treatment was incorporated in ground turkey breast and stored at 3°C for 0, 5, and 10 days. The treated samples were cooked to two different endpoint temperatures (74°C and 79°C) and stored at 3°C (4 and 24 hr) before cooking. An improvement of 77% and 80% was found in the reduction of Thiobarbituric Acid Reactive Substances (TBARS) with the 0.3% and 0.5% encapsulated STP, respectively, in comparison to the unencapsulated STP. The best results were seen with a shorter storage time (4 hr) prior to cooking and a higher endpoint temperature (79°C). The unencapsulated and encapsulated STP were compared to commercial antioxidant blends, Lemo-fos and Freez-Gard FP 15, at a level of 0.5%, to determine differences in their capabilities of lipid oxidation reduction. The encapsulated phosphate was lower (P<0.05) in TBARS (3.5 mg/kg) in comparison to the treatments which ranged from 15.6 to 20.4 mg/kg. However, the CIE a* values were higher in the encapsulated samples due to the decrease in lipid oxidation. The effect of liquid nitrogen on TBARS values was investigated to identify a means of analyzing a large quantity of samples. The use of cryogenic freezing was not significantly different in TBARS in comparison with a fresh, unfrozen control. Raw and cooked ground turkey samples were submerged into liquid nitrogen and stored intact or immediately reduced in particle size to compare particle reduction effects on TBARS. The different particle reduction methods were not significantly different, although, the immediately reduced sample was more efficient in TBARS determination. The samples stored in an ultralow freezer (-80°C) for 14 and 33 days were not different (P>0.05). Overall, when encapsulated STP is used with sufficient pre-cook storage time, lipid oxidation can be more effectively reduced than with the use of unencapsulated phosphates. The use of cryogenic freezing and ultralow temperature storage can also aid in the determination of lipid oxidation in large sample quantities due to the stability of TBARS values. / Master of Science

Two experiments were conducted to determine the efficacy of supplemented feedstuffs to improve the performance of cattle consuming fescue-based rations. The objective of the first experiment was to evaluate growth and reproductive characteristics of heifers consuming endophyte-infected (EI) fescue seed with or without sodium bicarbonate supplementation. Forty-eight heifers (8 mo; BW = 268 ± 24 kg) were utilized in a 2 x 2 factorial design. Treatments were either high-EI fescue seed without sodium bicarbonate (E+B-), high-EI fescue seed with sodium bicarbonate supplementation (E+B+), low-EI fescue seed without sodium bicarbonate (E-B-), or low-EI fescue seed with sodium bicarbonate supplementation (E-B+). At d 56, G:F (P= 0.084) and ADG (P = 0.071) tended to be improved for heifers fed E+B+. By d 84 bicarbonate supplementation tended to decrease ADG (P = 0.087). Bicarbonate supplementation ameliorated the negative effects of E+ at 28 d, but by d 84 negatively impacted animal performance. The objective of the second experiment was to determine the energy content of corn gluten feed (CGF) relative to corn in forage-based beef rations. Forty-two steers (13.8 ± 0.4 mo; BW = 382 ± 8 kg) were supplemented with either corn or CGF at 0.15% (L), 0.54% (M) or 0.96% (H) BW for 63 d. Steer ADG was greater for steers supplemented with CGF relative to steers supplemented with corn (P = 0.034). Energy value of CGF relative to corn was calculated by adjusting supplement TDN in the 2016 Nutrient Requirements of Beef Cattle Model. The energy values of CGF relative to corn were 106%, 107%, and 112% for L, M, and H. / Master of Science / Tall fescue is the predominant forage in the southeast United States, and has a symbiotic relationship with an endophytic fungus, providing drought and pest resistance to the plant. However, the fungal endophytes produce toxic ergot alkaloids which can result in decreased performance when cattle consume tall fescue. Performance losses, resulting from the consumption of these ergot alkaloids, are costly and economical strategies to reduce the negative impact of endophyte-infected fescue consumption on animal performance are needed. Previous research indicates that ruminal buffering capacity and nutrient uptake may be impaired in cattle consuming endophyte-infected fescue seed. Providing a dietary buffer is a low-cost strategy that my help to improve nutrient utilization in cattle, resulting in improved animal performance. Aside from reduced performance resulting from the consumption of ergot alkaloids, forage nutrient content can vary throughout the year, resulting in situations where the animals’ nutrient requirements are not met by the forage alone. Historically, corn has been the major energy supplement used, but recent data suggest that co-products of the corn sweetener and ethanol industries have greater energy compared to corn in both feedlot and forage-based beef rations. Supplementing corn gluten feed at low levels may improve performance of cattle consuming forage-based rations without driving up the cost of production. The objective of this thesis is to evaluate two strategies to mitigate the negative effects of endophyte-infected fescue consumption on animal performance. The first experiment was conducted to evaluate the efficacy of sodium bicarbonate to mitigate the negative effects of endophyte-infected fescue on replacement heifers. Heifers were fed a basal corn silage diet. Fescue seed and bicarbonate were supplemented at 1.5 kg/day and 0.25 kg/day, respectively. After a 56 d treatment period, bicarbonate supplementation tended to improve performance of heifers fed endophyte-infected seed with bicarbonate relative to those fed un-infected seed without bicarbonate supplementation. However, by d 84 of the experiment, the benefits of bicarbonate supplementation were no longer observed. More research is needed to understand why the benefits of sodium bicarbonate supplementation were not sustained over the full experimental period. The second experiment was conducted to evaluate the feeding value of corn gluten feed relative to corn when fed to steers consuming a forage-based ration. Steers had free-choice access to fescue hay, and individual hay and supplement intake were recorded daily. Steers supplemented with corn gluten feed had greater average daily gain than steers supplemented corn. This translated to a greater energy value relative to corn for all inclusion levels, exceeding model predictions. These experiments help to shed light on low-cost solutions to improve performance and profitability for fescue forage-based beef production systems.

The objectives of the study were to create a scoring system to assess maternal behavior within 24-h of calving in crossbred beef cows; determine the impact of maternal scores on cow productive responses and evaluate how maternal score varies over animal lifetime; and assess the effect of maternal aggression and perceived mothering ability on calf survivability and growth performance. Calving observations (n = 1,832) were conducted across 12 calf crops from 2017 to 2022 from 680 unique crossbred cows at the Prairie Research Unit, Prairie, MS. Along with routine data collection, dams were subjectively scored for the traits maternal aggression (MA) and mothering ability (MOM). During calf processing MA score was recorded as: 1 = dam not attentive to calf, flees; 2 = dam unsure, may retreat but returns to check on calf; 3 = dam stays, non-aggressive; 4 = dam very attentive, may snort, paw, and/or vocalizes to calf; or 5 = dam very aggressive, vocalizes to humans, displays fight response. Immediately following calf processing, MOM score was collected and defined as: 1 = dam flees without calf; 2 = dam retreats quickly with calf, may vocalize for calf, stops short distance away and nurtures calf; 3 = dam and calf flee quickly, calf led; 4 = dam checks on and then walks away with calf; or 5 = dam and calf stay in immediate area, dam licks or otherwise nurtures calf. Variation existed for both MA and MOM within this sample, with distribution of both affected (P < 0.01) by calf crop and parity. Dams with MA score 1 and 2 had longer (P < 0.01) calving intervals compared to dams with MA scores of 3, 4, or 5. A MOM effect was detected (P < 0.01) for calf weaning age, which was greater (P ≤ 0.05) for dams with MOM score 1, 2, and 3 vs. dams with MOM scores 4, and 5No MOM differences (P ≥ 0.31) were detected for calf 205-d adjusted weaning BW, ADG from birth to weaning, or weaning rate.

A preliminary trial to determine the effect of repeated freezing and thawing on beef striploins, showed that the effect of thawing on frozen non-aged beef significantly improved tenderness, flavour and acceptability, indicating that thawing had a similar effect to aging. In the subsequent study, 207 beef striploins were collected from the Southern Crossbreeding Project (SXB: 70 heifers grainfed for 80 days, 70 steers grainfed for 180 days), Davies Gene Mapping Project (DGM: 30 steers grainfed for 180 days) and also 37 Hanwoo striploins imported into Australia from Korea. SXB animals consisted of Hereford cross calves sired by Belgian Blue, Limousin, South Devon, Hereford, Angus, Wagyu and Jersey bulls. DGM animals consisted of purebred Limousins and Jerseys and Limousin by Jersey crosses. Sensory analysis of beef striploins involved semi-trained taste panel assessments, using nine-point category scales for initial and sustained juiciness, beef flavour, beef fat flavour, oily flavour, buttery flavour, chicken-skin flavour, corn flavour, grassy flavour and overall acceptability. Flavour acceptability was positively enhanced by increased levels of intramuscular fat (IMF%). Significant differences in breed were apparent for juiciness, beef flavour, buttery flavour and flavour acceptability, after adjusting data to a constant level of intramuscular fat, suggesting that some variation in flavour may be genetic. The Korean Hanwoo displayed a numerically higher intensity of chicken score and lower intensity of beef flavour. Australian cattle breeds differed in fatty acid composition between each other and also to that of the Korean Hanwoo. The latter had 57% mono-unsaturated fatty acids, which was significantly higher (P<0.001) than the Australian breeds (47%). Since IMF% was confounded with breed, breed differences were not significant when adjusted for IMF%. Jersey animals most closely resembled the Hanwoo in fatty acid profile, whilst animals containing Limousin differed markedly from the Hanwoo. A chemical sensor was able to establish significant differences between Korean Hanwoo and Australian animals and predominantly mirrored differences in fatty acid composition and to some extent flavour. Development of prediction equations from individual fatty acids was disappointing (R2< 15%). However, when fatty acid data, IMF% and chemical sensor data were combined to form prediction equations, moderate R2 values were obtained of (24% to 43%). / Thesis (M.Ag.Sc.)--School of Agriculture & Wine, 2001.

In an effort to increase beef demand, the beef industry has expanded beyond commodity beef merchandizing into value-added cuts. As these beef cuts are developed it is critical that the industry be able to characterize the flavor attributes of these products. A trained sensory panel is typically utilized to determine flavor characteristics of food products including beef. Prior to product evaluation, a product lexicon or dictionary of terms is developed in order to anchor and orient panelists to the various samples. Once the lexicon is developed, it can be used by a descriptive panel to evaluate samples. Currently, the beef industry does not have a full beef flavor lexicon with defined references; therefore a comprehensive sensory lexicon for describing the aroma and flavor of beef was developed by a 6-member panel at Kansas State University with extensive experience in lexicon development and descriptive analysis. Three descriptive panels utilized the beef flavor lexicon developed in Phase I by Kansas State University to evaluate the effect of USDA Quality Grade and cut on beef flavor and to validate the beef flavor lexicon to determine if it is ready for use by scientists. iv Results indicated that Choice steaks and roasts were higher in fat-like, and overall sweet flavor. Eye of round roasts were lowest in aroma and flavor attributes and bottom round roasts were highest in liver-like flavor. Flat iron steaks were highest in fat-like flavor compared to other cuts and top loin steaks tended to have the lowest intensity in flavor attributes compared to the steak cuts. The three sensory panels rated steaks and roasts similarly for aroma and flavor attributes and were generally less than 2- to 1-point different in rating intensities. The beef flavor lexicon was easily applied across the three institutions and should be ready to be used as a viable research and product development tool.

Genetic parameters were estimated using 8086 weaning weight records of Mashona cattle from commercial herds in Zimbabwe, through Derivative-free Restricted Maximum Likelihood (DFREML) procedure fitting an individual animal model. All known additive relationships among animals were incorporated and all sires were assumed to have been bred by unknown parents. A simulation study was carried out to estimate the amount of bias in the estimated genetic parameters caused by the failure to account for the true relationships among the breeding animals. / Genetic differences between the weaning weights of Mashona cattle in commercial herds and in small holder herds were estimated using performance records of progeny from 2 reference bulls, 3 bulls from commercial herds, 14 bulls from Makoholi Research Station and 20 bulls from small holder farms. The findings from this study were used as a basis for simulating different strategies of improving the weaning weights of Mashona cattle through the creation of nucleus herds. Estimates ($ pm$s.e) of direct heritability (h$ sb{ rm A} sp2$), maternal heritability (h$ sb{ rm M} sp2$) and the correlation between direct and maternal genetic effects (r$ sb{ rm AM}$) were 0.243 $ pm$ 0.046, 0.392 $ pm$ 0.031 and $-$0.282 $ pm$ 0.081, respectively. When a permanent environmental effect of the dam (c$ sp2$) was fitted, the estimates of h$ sb{ rm A} sp2$, h$ sb{ rm M} sp2$, r$ sb{ rm AM}$ and c$ sp2$ were 0.281 $ pm$ 0.026, 0.113 $ pm$ 0.022, $-$0.269 $ pm$ 0.106 and 0.228 $ pm$ 0.023, respectively. No significant trends were observed in direct breeding values but there was a decline in maternal breeding values. The simulation study indicated that the bias in h$ sb{ rm A} sp2$ and h$ sb{ rm M} sp2$ resulting from the lack of sire pedigrees was trivial if the correlation between direct and maternal genetic effects was high and a large proportion of dams had known pedigrees. / The progeny test showed that both the mean breeding values of the reference sires and the bulls from commercial farms were significantly higher than the mean breeding values of small holder bulls for birth weight (by 1.6 and 1.7 kg, respectively) and weaning weight (by 10.4 and 11.0 kg, respectively). The strategies that selected breeding animals on their maternal genetic values resulted in the highest responses for weaning weight. / It was concluded that maternal genetic values of Mashona cattle should be improved to allow this breed to compete favourably as a maternal breed in commercial agriculture.

Graduation date: 1971

Thesis (Ph. D.)--University of Wyoming, 2005. / Title from PDF title page (viewed on Nov. 2, 2007). Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 81-90). Also available on the Internet.