Browsing by Subject "Cattle -- Feeding and feeds"
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Item A beef cattle research facility(Texas Tech University, 1989-12) Cooper, Patrick C.Beefcattle are the most important livestock in the agricultural economy of Texas. Central West Texas is the center of the U.S. cattle feeding industry producing twenty-two percent of the nation's supply of fed beef. During 1984, over five millon cattle were fed in this area, making Central West Texas cattle feeding a $3.5 billion industry. Beef is very popular, yet with greater national awareness of diet and health, the cattle feeding industry has had to place much emphasis on producing leaner beef. This has been accomplished to some extent with conventional research, but new technologies must be applied to make major advances in the economic efficiency of feeding cattle. The new existing facilities are soley pragmatic solutions consistíng of cormgated steel buildings with no regard to form, space, or image. Architecture, through form, space, and expression of technology and stucture, can enhance the educatíonal and research aspects of the agricultural industry and possibly give it its own new image.Item Cattle grazing dynamics under continuous and rotational grazing on sandy rangeland(Texas Tech University, 1990-08) Weir, John RobertCattle performance was evaluated for 161 consecutive days on a ranch in eastern New Mexico, in three cells managed under rotational grazing (RG) and in three pastures under continuous grazing (CG). Objectives were to examine animal performance, diet composition, diet quality, grazing behavior and plant selectivity from these CG and RG systems that were stocked at the same rates (east-26 ac/head, middle-19 ac/head, and west-23 ac/head). Average daily weight gains were greater (P<0.05) for CG cattle, 2.52 lb, than for RG cattle, 2.18 lb. No differences (P<0.05) in grazing time (CG-771 min, RG-794 min), loafing time (CG-627 min, RG-607 min) and rapid eye movement sleep time (CG-42 min, RG-40 min) were recorded between grazing systems. The RG cattle avidly selected certain plant species when first allowed into a new pasture; species selection changed by the second observation. Differences in plant species selection by CG cattle were not as pronounced as RG cattle. No differences (P<0.05) in diet composition occurred between the two grazing treatments, with 24 and 23 species of plants found in the diets of CG and RG cattle, respectively. Gummy lovegrass, fall witchgrass and sand dropseed were the main species occurring in the diets. Diet quality, evaluated using fecal crude protein was 7.0% and 7.1% for the CG and RG,respectively. Ko differences (?<0.05) were observed in forage samples hand-picked fror. RG and CG pastures when analyzed for crude protein (CG- 6.5%, RG-6.1%), phosphorus (CG-.13%, RG-.14%), in vitro dry matter digestibility (CG and RG-38%), neutral detergent fiber (CG-70%, RG-72%), and acid detergent fiber (CG and RG-38%). Selective grazing, which may reduce intake, by the RG cattle offers at least one possible explanation for lower daily gains by RG cattle than CG cattle.Item Comparative Food habits and Range use of Pronghorn and Cattle in the Texas Panhandle(Texas Tech University, 1982-08) Roebuck, Craig MoorePronghorn in the Texas Panhandle occur on scattered, isolated islands of uncultivated prairie. With changing land use patterns in the Panhandle, there is some concern about the ability of pronghorn to cope with habitat alterations. This study was designed: (1) to determine the plant species most commonly eaten by sympatric pronghorn and cattle in 3 study areas, (2) to assess the availability and degree of utilization of the vegetation in each study area, and (3) to assess the dietary flexibility and overlap between pronghorn and cattle, and compatibility of pronghorn with livestock grazing within and between 3 habitats. Three vegetatively different areas were chosen for study, ranging from the open prairie grassland of the High Plains, to the mesquite (Prosopis glandulosa) savanna of the Rolling Plains, to the shinnery oak (Quercus havardii) Sandhills. Forbs made up the bulk of the pronghorn diet (68%-90%) on all sites and showed little seasonal variation, regardless of different forb availabilities among study areas. Grass use was minor and ranged from l%-4% of the annual diet among study areas. Use of shrubs occurred only when forbs were not available (4%-22% of the diet among areas). The percentage that each food plant occurred in the diet was divided by the percentage it occurred on the range to yield a Selection Index (SI). Although flexibility in pronghorn diets was not seen, almost all food plants were selected with Si's greater than 1.0, indicating a high degree of selectivity. Cattle ate mainly grass on all areas (46%-63%). Forbs constituted 12%-31% of the annual diet among areas and shrub use was 2%-20%. Cattle were less selective in feeding than pronghorn in that many of the major dietary items had Si's at or near 1.0. Dietary overlap of pronghorn and cattle varied among areas and ranged from 10%-37%. Data suggested that dietary overlap among areas varied inversely with the quality of pronghorn habitat. Habitat vii selection data indicated pronghorn used open, gently rolling areas, and significant preference/avoidance for different vegetation types was expressed only on the Rolling Plains where vegetation types were highly varied. Factors affecting the use of different pastures by pronghorn were similar among areas; vegetative composition appeared to be more important than the presence or absence of cattle. Thus, pronghorn range use data indicated that separation from cattle was not maintained spatially (via pasture or vegetation type use), but maintained through selective food habits and grazing. Competition for forage with cattle was not as important as quality of habitat in determining pronghorn success in the Texas Panhandle. VlllItem Comparison of first and last grazers and continuous grazing schemes on short grass range in the Panhandle of Texas(Texas Tech University, 1986-05) Mowrey, Daniel PatrickNot availableItem Correlation of in vitro versus in vivo digestion and animal performance utilizing an all-concentrate ration(Texas Tech University, 1965-08) Simnacher, Albert AdolphNot availableItem Deferred grain rations with and without supplemental additives for fattening cattle: part I(Texas Tech University, 1954-08) Garner, Neal TNot availableItem Deferred grain rations with and without supplemental additives for fattening cattle: part II(Texas Tech University, 1955-08) Standlee, William JNot availableItem Deferred Grain Rations With and Without Supplemental Additives for Fattening Cattle: part III, 1956(Texas Tech University, 1958-08) Howard, Jimmy LaverneNot Available.Item Effect of dietary crude protein level and degradability on performance and carcass characteristics of growing and finishing beef calves(Texas Tech University, 2003-05) Gleghorn, JustinTwo experiments were conducted at two locations to determine the effects of dietary CP level and source on performance and carcass characteristics of beef steers, serum urea nitrogen (SUN), and evaluation of the metabolizable protein (MP) system. British x Continental steers were blocked by BW (357 ± 28 and 305 ± 25 kg initial BW; n = 360 and 225; four and five pens/treatment in Exp. 1 and 2, respectively). Steam-flaked corn-based diets were arranged in a 3 x 3 factorial with three CP levels (11.5, 13, or 14.5% of DM) and three sources of supplemental CP (N basis): 100% urea (U), 50:50 blend of urea and cottonseed meal (B), or 100% cottonseed meal (C). Steers in both experiments were initially implanted with Ralgro and reimplanted with Revalor-S on d 56. Performance and carcass data were pooled across locations and analyzed with mixed model procedures using pen as the experimental unit. Crude protein level quadratically affected ADG (P < 0.05) and carcass-adjusted (to a common dressing percent) ADG (P < 0.10). Increasing the level of supplemental urea linearly increased carcass-adjusted ADG and gain:feed (P < 0.05) and carcass-adjusted gain:feed (P < O.OOI). Dry matter intake was not affected by CP level or source (P > 0.10). Hot carcass weight (HCW), longissimus muscle area (LMA), and dressing percent tended to increase linearly with increasing urea level (P < 0.06), whereas increasing CP level quadratically affected HCW (P < 0.05), with a maximum value at 13% CP. Differences in backfat thickness and yield grade were negligible across treatments. Neither marbling score nor percentage of carcasses grading Choice was affected by CP level or source. Serum urea nitrogen concentrations were affected by CP level and source (P < 0.05) over time. At all times measured, SUN concentrations increased with increasing CP level, but effects of CP source were small and variable across time. Evaluation of the MP system (d 0 to End) revealed no relationship between actual shrunk weight gain (SWG) and MP allowable gain (P = 0.344) and undegraded intake protein intake (UIP; P = 0.209). Linear relationships between SWG and energy allowable gain (P < 0.0001), degraded intake protein intake (DIP; P = 0.0008), CP intake (P = 0.003), and total MP supply (P = 0.003) were determined. For d 0 to 56, there was no relationship between SWG and MP allowable gain (P = 0.143) and between SWG and total MP supply (P = 0.143). However, linear relationships were noted between SWG and energy allowable gain (P < 0.0001), DIP intake (P < 0.0001), UIP intake (P = 0.002), and CP intake (P < 0.0001). Results indicate that increasing CP levels from 11.5 to 13% slightly increased ADG and carcass-adjusted ADG, whereas increasing the proportion of supplemental urea increased carcass-adjusted ADG, gain:feed, carcass-adjusted gain:feed, HCW, LMA, and dressing percent. A CP level above 13%) seemed to be detrimental to ADG and HCW. Serum urea N increased over time with increased dietary CP, but the response to CP source was variable. Evaluation of the MP system revealed no relationship between SWG and MP allowable gain; however, a strong linear relationship between SWG and energy allowable gain was observed.Item Effect of methods of processing upon digestibility of a new wheat by sheep and cattle(Texas Tech University, 1970-12) Cornett, Clifford DanNot availableItem Effect of protein source and level on performance of feedlot cattle(Texas Tech University, 1987-08) Eck, Thomas PeterNot availableItem Effects of feeding direct-fed microbials and prebiotics on receiving calf performance, health, and fecal shedding of pathogens(Texas Tech University, 2001-08) Abney, Michael D.Not availableItem Effects of live cultures of Lactobacillus acidophilus on performance and carcass characteristics of finishing beef steers(Texas Tech University, 2004-05) Osborn, GarySelected strains of Lactobacillus acidophilus have been shown to decrease the presence of E. coli 0157 in the feces of finishing cattle. For this experiment, 300 beef steers (British and Continental breeding; initial BW = 272 ± 25.5 kg) were used to determine the effects of live cultures of Lactobacillus acidophilus strain 45 / and or strain 51 and Propionibacterium freudenreichii strain 24 on performance and carcass characteristics during the finishing phase. Steers were fed a steam-flaked corn-based, 92% concentrate diet for an average of 141 d. Five treatments were included in the experiment: (1) control, lactose carrier only (C); (2) 1 x 109 cfu of Propionibacterim freudenreichii (NP 24) plus 109 cfu Lactobacillus acidphilus (NP 51) per steer daily plus 106 cfu of Lactobacillus acidophilus (HV 45) per steer daily (H+); (3) 109 cfu Propionibacterium freudenreichii (NP 24) plus l07 cfu Lactobacillus acidophilus (NP 51) per steer daily (L); (4) 109 cfu Propionibacterium freudenreichii (NP 24) plus 108 cfu Lactobacillus acidophilus (NP 51) per steer daily (M); and (5) 109 cfu Propionibacterium freudenreichii (NP 21) plus 10^ Lactobacillus acidophilus (NP 51) per steer daily (H). Nutrition Physiology Corp., Indianapolis IN, supplied all prepackaged DFM treatments. A randomized complete block design was used with pen as the experimental unit (12 pens/treatment). Orthogonal contrasts (C vs. others; linear and quadratic effects of NP51 dose [L; M, and H]; and H vs. H+) were used to evaluate treatment means. No differences {P > 0.10) among treatments were detected for final BW, DMI, or hot carcass weight. A quadratic effect {P = 0.09) of NP51 level on F:G for d 0 to 56 was noted, and a linear effect of NP51 level for F:G (P = 0.09) was evident for d 0 to 84 of the feeding period. For ADG, a trend (P = 0.12) for a linear effect of NP51 dose level for d 0 to 28 was observed. The contrast of control vs. treated steers was significant (P = 0.01) for DP as well as for KPH and for yield grade (P = 0.04). Similarly, there was a tendency (P = 0.12) for greater longissimus muscle area (LMA) in control vs. treated steers. A trend (P = 0.15) for a quadratic effect of NP51 dose level also was evident for LMA, with lower values for the M vs. H and L treatments. The percentage of Choice carcasses responded quadratically (P > 0.04) to NP51 levels with the highest percentage of Choice carcasses in the M treatment group. Overall, these data indicated that the introduction of live cultures of LA plus PF had no ill effects on feedlot performance under the conditions of the trial. Moreover, the use of DFM to control the shedding of E. coli 0157 could be very beneficial for the food safety.Item Effects of protein supplementation on steers grazing dormant tobosagrass(Texas Tech University, 1995-05) Villalobos, CarlosStudies were conducted through the 1989-90, 1990-91, and 1991-92 winter seasons at the Texas Tech Experimental Ranch, close to Justiceburg, Texas. The objective was to evaluate the effects of feeding various levels of cottonseed meal pellets (CSM) (0.00, 0.68 and 1.36 kg/hd/d) to steers on a tobosagrass range to determine weight gain. In addition, the effects of feeding those supplementation levels on forage intake and in vitro organic matter disappearance were evaluated during the winter seasons of 1989-90 and 1990-91. Furthermore, additional studies were done regarding in situ protein and organic matter disappearance from the forage and from the supplement, and the rumen degraded nitrogen:rumen degraded organic matter (RDNrRDOM, g/kg^-1) ratio of the complete diet on steers grazing dormant tobosagrass. I concluded that protein supplementation had a positive effect {P<0.05) on stocker cattle grazing dormant tobosagrass. Protein supplementation was most effective (P<0.05) during the second grazing period (mid-winter) and on colder winters rather than in mild ones. Average daily gain was 73.0 and 82.0% higher for the low and high levels of supplementation than for the control steers during the 3 years of this study. In conclusion, this study illustrated that protein levels did not affect (P>0.05) forage intake nor fecal output. Rate and extent of in situ digestion of protein and organic matter from the forage were modified (P<0.05) by the level of supplementation. Total protein degradation as well as the protein fractions decreased (P<0.05) along with the grazing periods, having the lowest values in the second grazing period. The level of protein supplementation slightly affected protein disappearance and organic matter from the supplement. The soluble protein or fraction A from the cottonseed meal (CSM) remained uniform during the 2 years of study. In contrast, the slowly degradable and undegradable fractions showed different patterns. Ruminal escape protein from CSM was similar between the 2 levels of protein supplementation, but different (P<0.05) across sampling periods. Results from RDN/RDOM ratios also suggested to feed the low rate of supplementation at the beginning and towards the end of the winter and to go to the high level at midwinter. Protein supplementation was most effective during the second period in which the lowest forage protein contents were found. These data indicated that feed protein escape values may differ on different range types, even within one winter. These results illustrated that no single estimate of protein escape can be applied to these feeding conditions. Consequently, there should be a combination of feeding a rumen degradable (CSC) with an escape protein to have better animal performance.Item Energy and Fiber Relationships in Steer Finishing Rations(Texas Tech University, 1973-05) Chrismon, Gary LynnNot Available.Item Feedlot and carcass characteristics of Santa Gertrudis steers as influenced by various processed sorghum grains(Texas Tech University, 1967-06) Holmes, John ColeyNot availableItem Foraging behavior and nutrition of grazing steers as influenced by protein supplementation(Texas Tech University, 1988-05) Maiga, Mouslim AStudies were conducted through the growing seasons (April to July) of 1985 and 1986 on tobosagrass (Hilaria mutica [Buckl.] Benth.) rangeland in West Texas. The objective was to evaluate the effects of feeding various levels of cottonseed meal supplement (0.00, 0.34, and 0.68 kg/(hd/d) on the foraging behavior, voluntary intake, dietary selectivity and digestive kinetics in grazing steers. Steers grazed under a 6- paddock short duration grazing system. Length of stay in a paddock was four to seven days. Behavioral observations were made on sixty to seventy steers while grazing in a predetermined paddock. The length of time steers spent at a feeding station, number of bites at a feeding station, number of steps between stations, and total daily grazing time were measured. Indices of foraging efficiency (bite to step ratio, biting rate, feeding time to step ratio, proportion of time spent feeding) were calculated. Particulate passage rate, liquid dilution rate, rumen fermentation, intake and botanical and chemical composition of diets were determined using rumen cannulated and esophageal fistulated steers. Foraging behavior was sensitive to level of supplementation depending upon the grazing cycle and length of stay in a paddock. Supplementation improved foraging efficiency (bite to step ratio, proportion of time spent feeding, feeding time to step ratio) and total daily grazing time as forage availability declined over days within a grazing cycle. Grazing time increased (P < .05) with length of stay in a paddock. Forage intake was not affected (P > .05) by protein supplementation although there was a tendency toward higher intake as level of supplementation increased. Particulate passage rate increased linearly (P < .05) with level of supplementation, while undigested dry matter fill decreased linearly (P < .05) with increasing level of supplementation. Protein supplementation increased (P < .01) liquid dilution rate and turnover rate and decreased (P < .05) turnover time. Total concentrations of volatile fatty acids increased (P < .05) with level of supplementation. However, supplementation did not change (P > .10) molar proportions of acetate, propionate, butyrate and branched chain volatile fatty acids. Rumen ammonia N concentrations were not different (P > .10) between levels of supplementation. Differences due to grazing cycle were noted for forage intake and all the parameters of digestive kinetics. These differences reflected changes in diet botanical composition estimates. Grazing cycle and length of stay in a paddock affected (P < .05) types of forage, plant parts and quality of diets consumed. Supplementation did not alter (P > .10) botanical and chemical composition of diets.Item Influence of certain endocrine factors on growth and fattening of steers under different nutritional conditions(Texas Tech University, 1968-08) Wiginton, Jay SpencerNot availableItem Investigations of bacteria in the rumen of cattle on all-concentrate diet compared to cattle on a high-roughage diet(Texas Tech University, 1965-05) Buchanan-Smith, Jock GordonNot availableItem Processing mesquite as a cattle feed(Texas Tech University, 1978-12) Fahle, David WayneNot available