Theses and Dissertations at Montana State University (MSU)
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Item Grazing, feed intake, and milk production differences in beef cows of varying efficiency classification and size(Montana State University - Bozeman, College of Agriculture, 2018) Williams, Alyson Rose; Chairperson, Graduate Committee: Timothy DelCurto; C.T. Parsons, J.G.P. Bowman, D.L. Boss and T. DelCurto were co-authors of the article, 'The influence of weaning weight ratio and cow size on feed intake behavior, milk yield, and milk constituents' submitted to the journal 'Journal of animal science' which is contained within this thesis.; S.A. Wyffels, C.T. Parsons, J.G.P. Bowman, D.L. Boss and T. DelCurto were co-authors of the article, 'The influence of weaning weight ratio and cow size on winter grazing and supplement intake behavior' submitted to the journal 'Journal of animal science' which is contained within this thesis.Metrics that identify beef cow efficiency in extensive rangeland environments has long been desired in both beef cattle research and production settings. However, research is limited relative to matching cattle metrics to western production systems. Previous research has suggested the ratio of calf weight weaned to cow weight, or weaning weight ratio, is an accurate estimate of cow efficiency. Furthermore, milk production has been attributed to influence calf pre-weaning average daily gain. Few studies have evaluated how cow type or cow characteristics influence grazing distribution and supplement consumption on native landscapes. The objectives of this study were to assess cow feed intake, grazing behavior, supplement intake, and milk production differences between cows of differing weaning weight ratio and body weight classification. Individual cow average daily feed consumption, average daily feeding bout duration, number of visits per day, and total time spent eating per day were collected during a feed intake period and a supplement intake period. Total distance traveled and time spent grazing were collected on individual cows with global positioning system collars. Milk samples were analyzed for fat, solids not fat, total solids, protein, and lactose content, and milk yield was calculated as the change in calf weight following a weigh-suckle-weigh procedure. High weaning weight ratio cows consumed more feed when expressed on a g/kg bodyweight basis (P < 0.001) but did not differ in supplement consumption (P > 0.10). High weaning weight ratio cows produced more milk both in total kg (P < 0.03) and when expressed as /kg bodyweight (P < 0.001). Heavy bodyweight cows tended to consume more feed than light bodyweight cows (P < 0.09) but neither bodyweight group ate more supplement than the other (P > 0.10). High weaning weight ratio cows spent an hour longer grazing per day than low weaning weight ratio cows (P < 0.02). Total distanced traveled per day did not differ (P > 0.10). Results suggest weaning weight ratio and cow size are not accurate metrics of cow efficiency and the use of weaning weight ratio may unintentionally favor cows with higher milk production and higher feed requirements.Item The effect of aureomycin upon lamb mortality and body weights and the effect of delayed feeding upon weaning weights(Montana State University - Bozeman, College of Agriculture, 1957) Bassett, James WilburItem The effects of calving date, weaning date, and duration of fall grazing on the sustainability of beef cow-calf operations in central and southeastern Montana(Montana State University - Bozeman, College of Agriculture, 1997) Julien, Debra JeanItem Production of two-year-old ewes(Montana State University - Bozeman, College of Agriculture, 1957) Colman, Kenneth L.; Chairperson, Graduate Committee: J. L. Van HornThe purpose of the investigation of these data was to explore the possibilities of relationships existing between the body weights of the ewes during their early life and their subsequent lamb and wool production as two-year-olds. The effects of environmental influences, such as type of birth and age at weaning, on the growth of ewe lambs and their production as two-year-olds were studied. The growth of two-hundred and fifty-nine ewes was measured by body weights taken at irregular intervals from birth to twenty-three months of age. Records of the individual lamb and wool production of these ewes were tabulated with the body weights. Results showed that the effect of type of birth and age at weaning, on body weights of ewe lambs was reduced as the lambs progressed toward maturity from weanling age. It was also found that the birth weights, weaning weights, and fall yearling weights of the ewes were significantly related. The fall yearling weight of the ewes was most indicative of two-year-old lamb and wool production. A significant relationship was found between the birth weights of the Rambouillet ewes and the pounds of lamb born per ewe as two-year-olds. The relationship between the birth weights of the Targhee ewes and the pounds of lamb born per ewe was not significant nor was this relationship significant for the birth weights of the Columbia ewes and the pounds of lamb born per ewe. The early single-born lambs were consistently lighter at birth than the late single-born lambs; however, at weaning time, the early single-born lambs were consistently heavier than the late single-born lambs. The average daily gain of the early single-born lambs and the late single-born lambs was about the same. The weaning weights of the ewes and their yearling fleece weights were significantly and positively related. The difference between the yearling fleece weights of the ewes and their two-year-old fleece weights was significant, the yearling fleece weights being the heaviest. It is evident from this study that valuable genetic breeding stock may be lost if suitable precautions are not taken to adjust for environmental conditions affecting the size of ewe lambs at weaning time when most replacements are selected. According to these data and that published previously by other workers, a sounder method of selecting higher producing replacements is to retain a larger number of ewe lambs at weaning and to make final selections at fall yearling age. Since production factors are closely related to body weight at fall yearling age, the heavier ewes of similar breeding will be better producers than the lighter ewes if selections are made at this age.Item Evaluation of pelleted or wafered rations for wintering or fattening beef cattle(Montana State University - Bozeman, College of Agriculture, 1965) Matz, John J.Item Measurements and effects of size in white leghorns and white leghorn bantams(Montana State University - Bozeman, College of Agriculture, 1970) Mecha, InyangItem A comprehensive analysis of pelvic measurements in beef cattle(Montana State University - Bozeman, College of Agriculture, 1991) Cook, Barry RogerItem Effect of disease on calf performance(Montana State University - Bozeman, College of Agriculture, 1996) Bernardini, Tracie-Marie MargaretItem The effect of dam milk production on daughter maternal ability in Hereford cattle(Montana State University - Bozeman, College of Agriculture, 1988) Reed, William AndrewItem Effect of beef cattle age, gender and barley grain processing method on rate and efficiency of gain and nutrient digestibilities(Montana State University - Bozeman, College of Agriculture, 2004) Rainey, Brian Michael; Chairperson, Graduate Committee: John Paterson; R.J. Lipsey (co-chair)Three experiments were conducted to test the effects of animal age (cows vs. calves) and barley processing method (whole vs. rolled) on rate and efficiency of gain and diet digestibility when barley was fed as a supplement to medium quality grass hay. A fourth experiment was conducted to test the effects of differences in diet composition on ADG and carcass characteristics in early-weaned calves. No age x processing interactions (P > 0.05) were detected for OM, N, ADF or NDF digestibilities. Diet OM and N digestibilities were greater (P < 0.01) when consumed by calves compared to cows, but ADF and NDF digestibilities were similar between ages. A processing method x age interaction was measured (P < 0.05) for starch digestibility. Rolling the barley dramatically improved starch digestibility when fed to cows (71.4% vs. 23.3% for rolled vs. whole). For experiment two, animals fed the hay only diet had similar (P > 0.05) rates and efficiencies of gain as diets supplemented with barley. Barley processing had no effect (P > 0.05) on rate or efficiency of gain for cows or calves. Cows were less efficient than calves (12.6 vs. 7.6) when fed similarly formulated diets. Unlike experiment 1, no differences were measured for digestibility of OM, N, ADF, NDF, or starch due to animal age or grain processing method. For experiment 4, calves fed barley gained faster (1.29 kg.d-1 vs. 0.99 kg.d-1; P = 0.002) and had higher marbling scores (4.44 vs. 3.31 %EEF; P = 0.002) compared to calves fed wheat midds during the first 34 d after weaning. However, gains during the 90 d after weanining were nonsignificant (1.36 vs. 1.24 kg.d-1 for barley and midds respectively). Calculated final live weights and marbling scores after 217 d of consuming a common finishing ration were similar for barley-fed calves compared to wheat midds-fed calves. Results suggest processing of barley may be of greater value for mature cows compared to younger calves, and barley had a greater effect on changing calf body composition than wheat midds. Cost·kg-1 gain was similar for whole vs. rolled barley diets.