Animal & Range Sciences
Permanent URI for this communityhttps://scholarworks.montana.edu/handle/1/9
The curricula in animal science provide students with a firm foundation in the biological and natural sciences, animal breeding, reproductive physiology, nutrition, and livestock production and management. Natural Resources & Rangeland Ecology focuses on managing the interaction of livestock, and wildlife and their rangeland habitats. Emphasis is placed on soil, water and vegetation attributes which influence habitat ecology and management of livestock and wildlife.
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Item Plasticity in the Human Gut Microbiome Defies Evolutionary Constraints(2019-07-19) Gomez, Andres; Sharma, Ashok Kumar; Mallott, Elizabeth K.; Petrzelkova, Klara J.; Jost Robinson, Carolyn A.; Yeoman, Carl J.; Carbonero, Franck; Pafco, Barbora; Rothman, Jessica M.; Ulanov, Alexander; Vlckova, Klara; Amato, Katherine R.; Schnorr, Stephanie L.; Dominy, Nathaniel J.; Modry, David; Todd, Angelique F.; Torralba, Manolito; Nelson, Karen E.; Burns, Michael B.; Blekhman, Ran; Remis, Melissa; Stumpf, Rebecca M.; Wilson, Brenda A.; Gaskins, H. Rex; Garber, Paul A.; White, Bryan A.; Leigh, Steven R.The gut microbiome of primates, including humans, is reported to closely follow host evolutionary history, with gut microbiome composition being specific to the genetic background of its primate host. However, the comparative models used to date have mainly included a limited set of closely related primates. To further understand the forces that shape the primate gut microbiome, with reference to human populations, we expanded the comparative analysis of variation among gut microbiome compositions and their primate hosts, including 9 different primate species and 4 human groups characterized by a diverse set of subsistence patterns (n = 448 samples). The results show that the taxonomic composition of the human gut microbiome, at the genus level, exhibits increased compositional plasticity. Specifically, we show unexpected similarities between African Old World monkeys that rely on eclectic foraging and human populations engaging in nonindustrial subsistence patterns; these similarities transcend host phylogenetic constraints. Thus, instead of following evolutionary trends that would make their microbiomes more similar to that of conspecifics or more phylogenetically similar apes, gut microbiome composition in humans from nonindustrial populations resembles that of generalist cercopithecine monkeys. We also document that wild cercopithecine monkeys with eclectic diets and humans following nonindustrial subsistence patterns harbor high gut microbiome diversity that is not only higher than that seen in humans engaging in industrialized lifestyles but also higher compared to wild primates that typically consume fiber-rich diets.Item Pelleted-hay alfalfa feed increases sheep wether weight gain and rumen bacterial richness over loose-hay alfalfa feed(2019-06) Ishaq, Suzanne L.; Lachman, Medora M.; Wenner, Benjamin A.; Baeza, Amy; Butler, Molly; Gates, Emily; Olivo, Sarah; Geddes, Julie Buono; Hatfield, Patrick G.; Yeoman, Carl J.Diet composed of smaller particles can improve feed intake, digestibility, and animal growth or health, but in ruminant species can reduce rumination and buffering – the loss of which may inhibit fermentation and digestibility. However, the explicit effect of particle size on the rumen microbiota remains untested, despite their crucial role in digestion. We evaluated the effects of reduced particle size on rumen microbiota by feeding long-stem (loose) alfalfa hay compared to a ground and pelleted version of the same alfalfa in yearling sheep wethers. In situ digestibility of the pelleted diet was greater at 48 h compared with loose hay; however, distribution of residual fecal particle sizes in sheep did not differ between the dietary treatments at any time point. Both average daily gain and feed efficiency were greater for the wethers consuming the pelleted diet. Observed bacterial richness was very low at the end of the adaptation period and increased over the course of the study, suggesting the rumen bacterial community was still in flux after two weeks of adaptation. The pelleted-hay diet group had a greater increase in bacterial richness, including common fibrolytic rumen inhabitants. The pelleted diet was positively associated with several Succiniclasticum, a Prevotella, and uncultured taxa in the Ruminococcaceae and Rickenellaceae families and Bacteroidales order. Pelleting an alfalfa hay diet for sheep does shift the rumen microbiome, though the interplay of diet particle size, retention and GI transit time, microbial fermentative and hydrolytic activity, and host growth or health is still largely unexplored.Item Ground-Dwelling Arthropod Community Response to Livestock Grazing: Implications for Avian Conservation(2019-08) Goosey, Hayes B.; Smith, Joseph T.; O'Neill, Kevin M.; Naugle, David E.Terrestrial arthropods are a critical component of rangeland ecosystems that convert primary production into resources for higher trophic levels. During spring and summer, select arthropod taxa are the primary food of breeding prairie birds, of which many are imperiled in North America. Livestock grazing is globally the most widespread rangeland use and can affect arthropod communities directly or indirectly through herbivory. To examine effects of management on arthropod community structure and avian food availability, we studied ground-dwelling arthropods on grazed and ungrazed sagebrush rangelands of central Montana. From 2012 to 2015, samples were taken from lands managed as part of a rest-rotation grazing program and from idle lands where livestock grazing has been absent for over a decade. Bird-food arthropods were twice as prevalent in managed pastures despite the doubling of overall activity-density of arthropods in idle pastures. Activity-density on idled lands was largely driven by a tripling of detritivores and a doubling in predators. Predator community structure was simplified on idled lands, where Lycosid spiders increased by fivefold. In contrast, managed lands supported a more diverse assemblage of ground-dwelling arthropods, which may be particularly beneficial for birds in these landscapes if, for example, diversity promotes temporal stability in this critical food resource. Our results suggest that periodic disturbance may enhance arthropod diversity, and that birds may benefit from livestock grazing with periodic rest or deferment.Item Habitat Relations of Mule Deer in the Texas Panhandle.(1985-11-27) Koerth, Benjamin H.; Sowell, Bok F.; Bryant, Fred C.; Wiggers, Ernie P.Telemetric observations of mule deer (Odocoileus hemionus) does were used to determine seasonal relationships between deer use and availability of habitats on two study areas in the Panhandle region of west Texas. Juniper breaks was the only type used in greater proportion than its availability on the Canadian River study area (CRSA). On the Clarendon study area (CSA) mule deer shifted seasonal preferences between riparian, cultivated fields, and juniper breaks. Annual and seasonal home ranges were considerably larger on the CSA. Larger home ranges and variability in seasonal use of the habitat types on the CSA were attributed largely to the presence of cultivated winter grain fields. Shifts in home ranges coincided with the season when production in the cultivated fields was highest and native forage availability was lowest. Comparisons of indirect deer observations (pellet groups and bed sites) with random measurements within each habitat type characterized deer use sites as east and north facing slopes, located close to a canyon rim, and receiving light livestock and human use. The placement of cultivated grain fields could be used to influence overall range use and attract deer to or away from localized sites. Also, consideration should be given to directing heavy livestock and human traffic away from sites that are used by mule deer.Item Protein Supplementation and 48-Hour Calf Removal Effects on Range Cows(1992-03) Sowell, Bok F.; Wallace, Joe D.; Parker, Eugene E.; Southward, Morris G.In 1984, 99 Angus × Hereford cows (4- to 6-yr-olds) were assigned randomly to a 4-yr, 2 × 2 factorial study. Treatment assignment was permanent, and no new cows were added during the study. By 1987, 71 cows remained, and over-all, 335 complete cow-calf data sets were used. Main effect treatments were beginning time (prepartum [PRE] vs postpartum [POST]) for crude protein (CP) supplementation (twice weekly feeding of 41% CP cottonseed meal pellets at 1.58 kg • $\text{cow}^{-1}$ • $\text{feeding}^{-1}$) and temporary calf removal (48 hour [48-H] vs 0 hour [CONT]) just before the breeding season. For analyses, sex of calf was included as a third main effect (2×2×2) and year was included as a random factor; the 4-way interaction served as the testing term for repeated measures over years. Year was the dominant source of variation for most traits; we attributed this mainly to different amounts and timing of precipitation among years. Very few interactions were observed. The PRE supplemented cows had reduced (P<0.01) spring body weight losses and higher prebreeding body condition scores (4.9 vs 4.5; P<0.01) compared with POST cows. Reproductive performance did not differ between PRE and POST cows. Use of 48-H calf removal vs CONT did not influence (P>0.10) reproductive traits measured. Likewise, 48-H treatment did not impair health or reduce weaning weights of calves. In a separate, within-year analysis used to examine age of dam effects, productivity of 4-yr-old cows during 1984 was slightly below that of older cows for some traits. Cow age effects were not detected in other years. We conclude that control cows in our study were approaching optimum fertility and production levels in concert with their environment and that improvement beyond these levels with the treatments imposed was unlikely.Item Application of Feeding Behaviour to Predict Morbidity of Newly Received Calves in a Commercial Feedlot.(2001-09) Quimby, W. F.; Sowell, Bok F.; Bowman, J. G. P; Branine, M. E.; Hubbert, M. E.; Sherwood, H. W.The objective of this study was to use feeding behavior of newly received steers (average initial weight 191 kg) to detect morbidity in animals in a commercial feedlot. Two separate 32 d feeding trials were conducted in Wellton, Arizona, in July and November 1996. Radio frequency technology was used to record the total time spent within 50 cm of the feedbunk (animal presence every 5.25 s times 5.25 s) in 3 h intervals from 0600 to 2400 on a daily basis for 103 and 122 male calves in trial 1 and 2, respectively. Statistical procedures based on the cumulative sums (CUSUM) of the 3 h feeding intervals were used to detect morbid animals, compared with detection of animals deemed morbid by experienced pen riders. In trial 1, the CUSUM procedure detected animal morbidity 4.5 d earlier (P < 0.001) than the feedlot personnel. In trial 2, the CUSUM procedure detected animal morbidity 3.7 d earlier (P < 0.001) than feedlot pen riders. Overall accuracy, positive predictive value and sensitivity of the CUSUM prediction method were 87, 91, and 90%, respectively. Combined trial data suggest that feeding behavior during the first 30 d cattle are in a receiving pen, as collected with radio frequency technology and analyzed with CUSUM charts, may be used to detect animal morbidity approximately 4.1 d earlier (P < 0.001) than conventional methods typically employed in commercial feedlots.Item Horses and Cattle Grazing on the Wyoming Red Desert, III.(1984-03) Plumb, G. E.; Krysl, L. J.; Hubbert, M. E.; Smith, M. A.; Waggoner, J. W.Vegetative cover losses due to trampling near watering sites in the summer and winter are compared for horses grazed alone, cattle grazed alone and horses and cattle grazed in combination. There were significant differences (p<.05) found in the rates of total cover loss as a function of distance to water in both the summer and winter. Grasses sustained heavy trampling losses in all treatments in both seasons. Forbs sustained heavy losses in all treatments during summer. Shrub losses were moderate to low in all treatments during both seasons. Total cover loss was similar in all summer and winter treatments.Item Horses and Cattle Grazing in the Wyoming Red Desert, II. Dietary Quality.(1984-05) Krysl, L. J.; Sowell, Bok F.; Hubbert, M. E.; Plumb, G. E.; Jewett, T. K.; Smith, M. A.; Waggoner, J. W.Botanical composition of horse and cattle diets from fecal analysis and nutrient quality of hand-harvested forages used by these herbivores were evaluated to assess dietary quality during the summer and winter seasons of 1981 in the Wyoming Red Desert. Dietary crude protein estimates averaged 7.5±0.1% and 9.0±0.5% during the summer for horses and cattle, respectively. Dietary crude protein estimates in the winter were lower, averaging 6.1±0% and 6.0±0% for horses and cattle, respectively. Estimated dietary calcium levels for both herbivores were high through the summer and winter, while dietary phosphorus levels appear to be deficient during both seasons. Average in vitro dry matter disappearance coefficients for horses and cattle during the summer were 52±2% and 52±2%, respectively. During the winter these values dropped to 39±1% and 40±1% for horses and cattle, respectively.Item Estimating Digestibility and Faecal Output in Lambs Using Internal and External Markers.(1988-08-01) Krysl, L. J.; Galyean, M. L.; Estell, R. E.; Sowell, Bok F.Twenty fine-wool, ruminally cannulated lambs (average weight 45–9 kg) were used in a completely random design to evaluate the ability of three internal markers to predict dry matter digestibility and two external markers to estimate faecal output. Lambs were allotted randomly to one of four diets: 100% prairie hay (PH), 100% lucerne hay (LH), 50% prairie hay:50% sorghum grain (PS) and 50% lucerne hay: 50% sorghum grain (LS). The trial consisted of a 14-day adaptation period followed by a 7-day total faecal collection period. Feed and faecal samples were subjected to 96 h ruminal fluid and 48 h acid-pepsin digestions, followed by extraction with acid detergent (IVADF) or neutral detergent (IVNDF) solution. Dry matter digestibility (DMD) calculated from feed:faeces ratios of IVADF, IVNDF and acid detergent lignin (ADL) was compared with in vivoapparent digestibility. Ytterbium-labelled forage (YLF) and dysprosium-labelled faeces (DLF) were pulse-dosed via ruminal cannulae, and faecal Yb and Dy excretion curves were fitted to a one-compartment, agedependent model for estimation of faecal output, paniculate passage rate (PPR) and mean gastrointestinal retention time. In vivoDMD in lambs fed PH was greater (P <005) than DMD calculated from IVNDF, IVADF and ADL. In lambs fed LH and LS, in vivoDMD did not differ (P >005) from marker estimates. In vivoDMD for lambs fed PS did not differ from IVNDF or IVADF estimates but was greater than (P <005) the ADL estimate. No differences (P> 005) were observed in recovery among the three internal markers for any of the diets. Faecal output for lambs fed PH did not differ {P >005) from marker estimates but was overestimated by 15 to 20% by YLF and DLF. Faecal output for lambs fed LH was similar to the estimate from YLF, but less than (P <0–05) the estimate with DLF. For lambs fed PS, faecal output did not differ from marker estimates, but YLF and DLF values were 16% lower and 17% higher, respectively. No significant differences were observed in actual and estimated faecal output for lambs fed the LS diet. Estimates of PPR with DLF were numerically greater than YLF estimates for all diets except LS. Correspondingly, mean gastrointestinal retention time was less (P <005) for DLF compared with YLF for all diets except LS.Item Horses and Cattle Grazing in the Wyoming Red Desert(1984-01) Krysl, L. J.; Hubbert, M. E.; Sowell, Bok F.; Plumb, G. E.; Jewett, T. K.; Smith, M. A.; Waggoner, J. W.The sagebrush-grass range in southcentral Wyoming presently supports large numbers of feral horses and domestic livestock. Diets of feral horses and cattle during summer and winter grazing were evaluated using fecal analysis under 2 stocking levels in small pastures. Horses and cattle consumed primarily grasses during the summer and winter. However, shrubs and forbs were also important dietary components. Needleandthread, Sandberg bluegrass, thickspike wheatgrass, Indian ricegrass, gray horsebrush, and winterfat were the major foods of horses and cattle during the summer and winter. Dietary overlap between horses and cattle during the summer averaged 72% and increased to 84% during the winter. Horses and cattle selected foods in a similar order.