The objectives of this study were to evaluate the levels of supplemental salt on low-quality forage intake, water intake, dry matter (DM) digestibility, and rumen fermentation. Six ruminally cannulated, Angus crossbred heifers (14 mo of age; 449 kg ± 24 kg body weight [BW]) were used in a dual 3 × 3 Latin square design. The heifers were housed in individual stalls with 2 animals assigned to each treatment per period.
View Article and Find Full Text PDFPulmonary arterial pressure (PAP) determines cattle's susceptibility to High Altitude Disease (HAD), also known as Brisket Disease, High Mountain Disease, and right-sided heart failure (RHF). This non-infectious disease causes pulmonary hypertension due to hypoxia. PAP measures the resistance of blood flow through the lungs.
View Article and Find Full Text PDFThe objective of this study was to characterize foot angle and claw set scores of Montana's (USA) registered Angus cattle using a total of 4723 cattle scored: 1475 yearling bulls, 992 yearling heifers, 1044 2- and 3-year-old cows, and 1212 cows ≥ 4 years old. Yearling bulls had a 0.12 and 0.
View Article and Find Full Text PDFUnderstanding the relationship of foot angle and claw set to beef cattle structural soundness will be critical to the selection of animals that fit forage-based production systems. In an effort to address concerns about foot and leg structure, the American Angus Association's foot angle and foot claw set expected progeny differences (EPD) were developed in 2019. As a result, these relatively new EPD and associated guidelines have limited phenotypic data submitted thus far.
View Article and Find Full Text PDFAngus and Red Angus-based yearling heifers (n = 40) and lactating cows (n = 51) were each used in a complete randomized design and stratified by weight and body condition score to one of two treatments: (1) pressed supplement block containing rumen undegradable protein (RUP) and (2) pressed supplement block containing rumen degradable protein (RDP). Heifer and cow supplement intake displayed (p < 0.01) a treatment × period interaction.
View Article and Find Full Text PDFThe objectives of this study were to evaluate the impacts of supplement form on supplement intake behavior, body weight (BW), and body condition score (BCS) change of yearling heifers grazing dryland pastures during the summer. In each of the two years, Angus crossbred heifers (14 mo of age; year 1, = 57, BW = 449 ± 3.60 kg; year 2, = 58, BW = 328 ± 3.
View Article and Find Full Text PDFHeifer post-weaning intake classification was utilized to evaluate subsequent intake and performance measurements of 2-, 5-, and 8-year-old lactating and non-lactating Angus females. For both studies, heifers were categorized based on voluntary feed intake (expressed as g/kg BW) as either low (<−0.50 SD from the mean), average (±0.
View Article and Find Full Text PDFThis study evaluated heifer post-weaning voluntary feed intake (g/kg BW) classification on performance and reproductive measures, as well as impacts on lifetime productivity of 519 commercial Angus beef females. Heifer post-weaning voluntary feed intake (g/kg BW) was calculated over 80 test days following weaning using GrowSafe units. Heifers were categorized based on voluntary feed intake (g/kg BW) as either low (<−0.
View Article and Find Full Text PDFThe objectives of this study were to evaluate the effect of differences in protein type and delivery method on rumen dynamics and nutrient digestion. Cows were allotted to rumen degradable protein (RDP) or rumen undegradable protein (RUP) and self-fed (SF) salt-limited pressed blocks or hand-fed (HF) loose supplement, resulting in four dietary treatments. There was a delivery effect ( = 0.
View Article and Find Full Text PDFThis study evaluated the effects of corn or barley finishing diets on ruminal pH and temperature and their relationship to feed intake events using continuous reticulorumen monitoring of feedlot steers. Average daily ruminal pH and temperature were not impacted ( ≥ 0.17) by diet.
View Article and Find Full Text PDFThis study evaluated heifer postweaning residual feed intake () classification on reproductive and performance measurements of first-, second-, and third-parity Angus beef females. We analyzed the annual, as well as, cumulative production of 347 Angus females from birth through weaning of their third calf. Heifer postweaning RFI was calculated as the actual dry matter intake minus the predicted dry matter intake based on the average daily gain of the contemporary group on an annual basis.
View Article and Find Full Text PDFWe evaluated heifer post-weaning residual feed intake (RFI) classification and cow age on dry matter intake (DMI) at two stages of production. Fifty-nine non-lactating, pregnant, (Study 1) and fifty-four lactating, non-pregnant (Study 2) commercial black Angus beef cows were grouped by age and RFI. Free-choice, hay pellets were fed in a GrowSafe feeding system.
View Article and Find Full Text PDFThe objectives of this study were to evaluate the influence of RFI and cow age on the supplement intake and grazing behavior of beef cattle. Average daily supplement intake (kg/cow/d) displayed an RFI × cow age interaction ( < 0.01), with a linear increase in average daily supplement intake with increasing RFI of 3-year-old cows ( < 0.
View Article and Find Full Text PDFThis study evaluated the influence of diet and environmental conditions on intake behavior and activity of feedlot steers. Feedlot rations used were comprised of a main concentrate: (1) corn or (2) barley. A GrowSafe system measured individual animal intake and behavior and HOBO accelerometers measured steer standing time.
View Article and Find Full Text PDFThis study evaluated the effects of barley and corn finishing rations on feedlot performance and behavior of steers. Feedlot rations in this study were comprised of a main concentrate of either corn or barley. Steers were fed in a GrowSafe system to measure individual animal intake and behavior.
View Article and Find Full Text PDFDormant season livestock grazing reduces reliance on harvested feeds, but typically requires protein supplementation to maintain animal performance. Individual variation in supplement intake can impact animal performance; however, it is unknown if this variation leads to individual or herd-level effects on grazing behavior, resource utilization, and grazing impacts to native rangelands. To examine effects of protein supplementation on dormant season cattle resource use and, subsequently, post-grazing habitat conditions, we examined cattle grazing behavior, resource utilization and biomass removal of vegetation on a native rangeland in Montana.
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