The cattle shown at the prestigious All-American Angus Futurity were studied in order to evaluate the relationship between various body measurements. The measurements taken included wither height, hip height, body length, fat thickness,and weight. Also, these measurements were analyzed in order to determine if Angus cattle had gained in genetic frame size. Data were collected for the 805 animals shown in the years 1974 through 1978. The cattle were grouped into classes based upon sex and age prior to any statistical procedures being performed. Means of classes were used in order to evaluate sex differences and bulls were found to be larger for all measurements. A comparison of the linear measurements and fat thickness of the old bulls with the corresponding measurements in the young bulls was utilized in a study of the maturity patterns present in the cattle. Also, coefficients of correlation were determined for all possible measurement combinations. The fat measurement was found to be less related to weight than either body length or body height. Wither height was the measurement most closely related to weight. Wither height measurement was used in an analysis of variance of year effect on frame size. There were highly significant differences in wither height that could be observed in the yearly means. The change in wither height was positive and consistent over the five years studied. The cattle did not increase in weight to the same degree that wither height changed and the changes in the fat measurements were inconsistent. However, the largest framed, leanest heifers occurred in 1978. The coefficients of correlation determined in this study support the use of linear measurements and fat measurement in addition to, or as a substitute for, weight in making selection decisions. Also, the regression equations developed help document the idea that it is possible to accurately predict weight through the use of skeletal measurements and fat thickness. The findings support the hypothesis that Angus cattle have become genetically larger framed over the past five years.

Utilizing local by-products can serve to significantly reduce the current feed costs for ruminant producers. The objective of this study is (1) to evaluate the effects of chemical and bacterial inoculants in combination with ensiling, on the nutritional value and ensiling compatibility of olive pomace (OP) and (2) to identify the most biologically favorable treatment and ensiling day of OP for feeding to cattle. Freshly centrifuged OP (Olivas de Oro Olive Company, Creston, CA) was treated with one of four treatments: (1) no additives (control; CONT); (2) urea applied at 5% of DM (UREA; Agrium U.S. Inc, Loveland, CO); (3) SiloSolve MC (SS; a mixture of Enterococcus faecium M74, Lactococcus lactis SR3.54, and Lactobacillus plantarum CH6072 applied at 1.5 x 105 cfu/g of fresh forage; Chr. Hansen A/S, Hørsholm, Denmark); (4) SiloSolve MC applied at the same rate as treatment 3 with calcium oxide (CAO; Flinn Scientific, Batavia, IL) applied at 5% of DM. Treated OP was ensiled in quintuplicates into 20-L laboratory silos with vents, which were sealed for 2, 10, 60, and 120 d in a completely randomized design. At 0 d, DM was 2 and 5% higher for UREA and CAO, respectively, while ash and pH were highest for CAO. Fat tended to be higher for SS and CP was highest for UREA by 60 d (23.8%). CAO had significantly lower fiber portions, ethanol and yeasts (P < 0.05), and higher acetic acid than CONT. No significant differences were observed at 12 and 24 h in situ compared to CONT, yet at 48 h, NDFD was greatest for CONT and SS (P < 0.001). Lactic acid increase with prolonged ensiling with UREA having the highest content at 120 d (0.716 %) and acetic decreased for CONT, SS, and CAO. SS contained the most LAB (8.5 log cfu/ fresh g). Yeasts, molds, and sugars significantly decreased with ensiling. In conclusion, OP was determined to be a viable nutritional source for ruminants given its chemical composition and effective preservation after 120 d of ensiling that could be improved with chemical and bacterial inoculants.

The objective of this study was to evaluate the relationship between hair coat shedding ability, apparent forage digestibility, and mineral status in Angus cattle. Fecal samples were collected on fall calving Angus cows for one week in March, May, and July from 2019-2022. Liver and plasma samples were collected in March and July each year. Fecal samples were analyzed for DM, ash, NDF, and ADF while liver and plasma were analyzed for mineral concentration. Data were analyzed using MIXED procedure of SAS with significance declared at P0.05. Interactions were detected for DM, NDF, ADF, and liver Fe concentration. The model included MFS, month, and MFS by month interaction for each response variable. Interpretation of results showed no clear trends or associations between hair coat shedding ability, apparent forage digestibility, and mineral status, but further investigation is needed to understand cow performance due to relationships between genes and environment.

Zinc (Zn) has numerous functions and life sustaining processes depend on the presence of Zn within the body. Zinc sulfate is a common form of Zn supplemented in the beef industry. Inorganic sulfate based minerals have been associated with negative rumen effects, mainly, decreased rumen fermentation and protozoa numbers. Our studies concluded no difference in digestibility of three different forms of Zn (zinc glycinate, zinc sulfate, and zinc hydroxychloride). Although overall digestibility did not change, there were specific mineral concentration differences after steers consumed concentrate treatment for 10 days. These differences implied that the mineral fed was consumed and absorbed in post-treatment sample collection of rumen fluid, plasma, and liver. Overall liver Zn levels were within normal ranges and implies the zn fed was absorbed. Based on the results of this study bioavailability of, zinc glycinate, zinc sulfate, or zinc hydroxychloride were similar.

The cattle shown from 1981 to 1984 at the American Angus Breeders' Futurity were studied to determine the relationship between linear measurements and the judge's subjective placings. Linear measurements taken prior to the showing included wither height, hip height, and body length for both bulls and heifers. In addition body weight and scrotal circumference were recorded for bulls. A total of 624 cattle were studied-- 407 heifers and 217 bulls. The cattle were divided into five groups by age and sex to analyze the annual difference in means and standard deviations for all recorded measurements. Among all five groups of cattle, hip height increased at the fastest rate from 1981 to 1984. All measurements had a positive increase except body weight and scrotal circumference. The older bulls decreased by 61.67 lbs. in weight from 1981 to 1984 and decreased by 1.78 in. in scrotal circumference between 1983 and 1984. Coefficients of correlation were obtained using the recorded measurements along with age for all five groups. Wither height showed the closest association to other measurements. Among all five groups body length had the most inconsistent association to other measurements, primarily due to difficulty involved in obtaining an accurate body length measurement. Spearman's coefficient of rank correlation was conducted to determine which measurements the judges were giving most emphasis in the showring. It seems apparent that judges are continuing to select for larger framed cattle, placing greater emphasis on wither and hip height measurements and lesser emphasis on body weight and scrotal circumference. The findings in this study support the fact that judges are selecting for larger framed, later maturing cattle with little if any selection being placed upon present weight or indicators of future reproductive performance.

The calves born in the 1979 and 1980 calf crops at Sam Sells and Sons' Polled Hereford Farm in Moultrie, Georgia, were used in a study comparing immature body measurements with subsequent growth. The measurements taken at birth included weight, front leg length, front cannon bone length, and rear cannon bone length. In addition, hip height was measured at one hundred days, seven months, and twelve months of age. Weight was taken at seven months, twelve months and fifteen months of age. The data were analyzed in four groups according to year of birth and sex. Coefficients of correlation were determined for all measurement combinations. Birth measurements alone accounted for an insignificant amount of the variability in twelve-month weight. Among the four groups studied, seven-month weight showed inconsistent associations to height and weight at twelve and fifteen months of age. This was due primarily to the amount of environmental influences involved in weight at seven months. Multiple regression analyses were conducted using twelve-month weight as a dependent variable and immature body measures as independent variables. An equation using one hundred-day hip height alone accounted for seventy-six percent of the variability in twelvemonth weight. Another equation including two independent variables, one hundred-day hip height and seven-month weight, accounted for eighty percent of the variability in twelvemonth weight. When twelve-month height was used for a dependent variable, one hundred-day hip height and rear cannon bone length at birth accounted for seventy percent of the variability. The coefficients of correlation and multiple regression equations reported in this study support the fact that linear measurements are a more consistent measure of size in immature calves than weight alone. Also, linear measurements show little or no variation due to environmental conditions such as age of dam, unpartitioned maternal ability and physiological changes associated with puberty. The findings support the hypothesis that immature linear skeletal measurements are accurate predictors of subsequent growth in Polled Hereford cattle.

Measures of temperament have been shown to influence physiological responses. Exit velocity (EV) has been identified as an objective, robust measure of temperament that can be used to predict subsequent performance of cattle. Additionally, previous studies from our lab indicate this measure of temperament may be related to production of interferon-γ (IFN-γ), a cytokine associated with cell-mediated immunity (CMI). Whereas research has investigated effects of EV upon immune responses, the overall goal of these studies was to examine this relationship under a variety of scenarios including human handling, transportation, and exposure to endophyte-infected tall fescue (E+) for determination of its ability to influence CMI in cattle. In each of 5 experiments, calves were classified as either high or low EV animals, based upon measurements obtained prior to initiation of experimental periods. The hypothesis for these studies was that calves with high exit velocities would have lower systemic immune responses to applied treatments. Two experiments were designed to examine the relationship between exit velocity and lymphocyte IFN-γ production during and following a period of exposure to E+ seed and increased temperature humidity index conditions. Preliminary measures of this cytokine indicated a positive relationship with EV. During application of heat and E+ treatment application, no differences in IFN-γ production were detected between EV or endophyte treatment groups. However, in both experiments, after temperatures were returned to thermoneutral and E+ heifers were placed on the endophyte-free treatment, the positive relationship between exit velocity and total lymphocyte production of IFN-γ observed in baseline samples was reestablished. Similarly, during an experiment examining IFN-γ production by lymphocytes in steers during the 4 weeks following a 10h, 805 km transport study, average lymphocyte production of IFN-γ was higher and lymphocyte proportions producing IFN-γ lower in low EV steers, but total lymphocyte production of this cytokine did not differ between exit velocity treatments. In a grazing and finishing study, cattle were placed on E+ or novel endophyte pastures, with balanced representation of low and high EV treatments within each pasture. During the subsequent finishing period, blood samples for lymphocyte IFN-γ production were collected from a single high EV calf from each pasture group. Neither endophyte nor exit velocity was detected to be related with lymphocyte production of IFN-γ. In an experiment examining changes in cytokine gene expression changes during acclimation to human handling, IFN-γ, Il-6, IL-10, and IL-12 were observed to increase linearly over the experimental period in all calves, irrespective of exit velocity designation. In the same experiment, whole period pro-inflammatory tumor necrosis factor-α expression was higher for high EV calves, but interferon-γ (IFN-γ) was lower in this same treatment group. These studies, cumulatively, indicate EV may be related to systemic production of IFN-γ, but abrupt changes to an animal’s environment may serve to mask this relationship.

The purpose of this research study was to compile regional profiles of the consumers who intend to consume grass-fed beef in the U.S. and to create marketing strategies that would assist producers in marketing their product to consumers. The researcher sent an online survey to a panel of 484 consumers across the U.S. to learn about their perceptions of and intention to purchase grass-fed beef. Respondents had a weak, positive attitude toward purchasing grass-fed beef but had low knowledge of production practices. These consumers had a desire to eat healthier; however, they wanted meat that was priced right and had a desirable leanness. Consumers were divided based on U.S. regions (Northeast, Midwest, South, and West) to determine any differences in their knowledge, attitudes, subjective norm, importance of quality cues, meat and beef consumption habits, beef consumption habits, and meal preparations. The information gathered from respondents was used to create a marketing plan for each region of the U.S. Recommendations for future research included exploring how the processing of meat, environmental attitudes, and eating habits influence consumers’ intention to purchase grass-fed beef. Information about consumer willingness to pay would also be helpful for grass-fed beef producers who are creating a marketing plan.

Cattle are responsible for greenhouse gas emissions such as carbon dioxide, methane and nitrous oxide. In particular, the cow-calf phase of production accounts for approximately 80 percent of the total beef production system greenhouse gas emissions. Tannins are chemical compounds found in certain forages and they have the potential to help reduce these negative environmental impacts. Thus, given that the cow-calf phase often relies on feeding hay, feeding tannin-containing hays may represent a significant mitigation practice. With my MS program, I sought to explore whether tannin-containing hays fed to mother cows and heifers influence methane and nitrogen emissions relative to feeding traditional legume and grass hays . I found that “non-traditional” hays such as cicer milkvetch and tannin-containing hays such as sainfoin, birdsfoot trefoil and small burnet can help mitigate greenhouse gas and nitrogen emissions produced from heifers and mature cows. Therefore, these hays could be used to feed cattle during the fall and winter to help create a more environmentally friendly cow-calf phase of beef production.

Consumption of endophyte-infected tall fescue results in a syndrome of negatively altered physiological systems, collectively known as fescue toxicosis. Another challenge to endophyte-infected tall fescue -based beef cattle operations is that the soils often are selenium (Se) poor, necessitating the need to provide supplemental Se. To test the general hypothesis that different forms of supplemental Se would ameliorate the negative effects of fescue toxicosis, predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing an endophyte-infected tall fescue pasture and consuming vitamin-mineral mixes that contained 35 ppm Se as sodium selenite (ISe), SELPLEX (OSe), or an 1:1 blend of ISe and OSe (MIX). Steers were commonly weaned and depleted of Se for 98 d. Steers were assigned (n = 8 per treatment) to the same Se-form treatments upon which they were raised and subjected to summer-long common grazing of an endophyte-infected tall fescue pasture (0.51 ppm ergot alkaloids: ergovaline plus ergovalinine; 10.1 ha). Selenium treatments were administered by daily top-dressing 85 g of vitamin-mineral mix onto 0.23 kg soyhulls, using in-pasture Calan gates. The first project objective was to determine the effect of forms of supplemental Se on whole blood Se, serum prolactin, liver glutamine synthetase (GS) activity, carcass parameters, and growth performance (Experiment 1). In Experiment 1, whole blood Se increased for all treatments from day 0 to 22 and then did not change. Across periods, MIX and OSe steers had greater whole blood Se than ISe steer. Compared to ISe steers, MIX and OSe steers had more serum prolactin. Liver GS mRNA, protein content, and activity were greater in MIX and OSe steers than ISe steers. However, the ADG and carcass parameters were not affected by Se treatments. The second project objective was to determine the effect of forms of supplemental Se on serum clinical parameters of Experiment 1 steers (Experiment 2). In Experiment 2, across periods, MIX steers had more serum albumin than OSe, and ISe steers, respectively. Serum alkaline phosphatase (ALP) activity was greater in MIX and OSe steers. In addition, blood urea nitrogen (BUN), serum sodium, phosphorus, and magnesium concentration were affected by Se treatments. Partial correlation analysis revealed that serum albumin, BUN, and ALP activity were correlated with whole blood Se concentration. The third project objective was to evaluate the hepatic transcriptome profiles of Experiment 1 steers using microarray and targeted RT-PCR analyses (Experiment 3). In Experiment 3, bioinformatic analysis of microarray data indicated that hepatic glutamate/glutamine, proline, arginine, and citrulline metabolism was affected by different forms of supplemental Se. The mRNA expression of critical proteins involved in glutamate/glutamine (GLS2, GLUD1, GLUL), proline (PYCR1, ALDH18A1), and urea (ARG1, ARG2, OAT, NAGS, OTC, ORNT1) metabolism were differentially expressed by Se treatments. Collectively, we conclude that consumption of 3 mg Se/d as OSe or MIX forms of Se in vitamin-mineral mixes 1) increased whole blood Se content, an indicator of greater whole-body Se assimilation; 2) increased serum prolactin, albumin, and ALP, the reduction of which are hallmarks of fescue toxicosis; and 3) altered hepatic nitrogen metabolism, as indicated by changes in key enzymes of glutamate/glutamine, proline, and urea metabolism. However, 4) these positive effects on metabolic parameters were not accompanied by increased growth performance.