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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

The Effect of Feeding Sucrose to Beef and Swine on the Percentage of Carbohydrate, pH, Color, Texture, and Flavor of Muscle and Liver

Merkley, Margaret B. 01 May 1952 (has links)
Carbohydrates have long been a part of animal feeding rations.Grains are included in all animal feeding formulas. The by-products of sugar beets have been used for many years in livestock feeding (Kutish 1950b). The use of molasses in commercial feed mixed in 1899 made possible its extended use in animal feeding practices (Hall 1950). Protein feeds for cattle are relatively high in price and not available in adequate supply. With these fats in mind Culbertson of Iowa State College set up experiments in 1950 to find out whether part or all of the protein supplement could be replaced with non-protein nitrogen feed in a good steer fattening ratio. The sugar in cane molasses is utilized more readily by animals than starch in corn grain, so molasses was fed to steers in the non-protein nitrogen feed. The growth made by the steers fed on these rations was on a par with the control group and use of these non-protein feeds in rations is likely to be of economical and practical importance. These findings have been verified by feeding large numbers of cattle (Bode 1951). Direct molasses usage on farms may be divided into two types: direct use as feed; and use as a preservative in making grass silage. At present the first type is more important, the second being used throughout the dairy belt (Kutsh 1950a; Aries and Copulsky 1949). Regarding amounts of molasses which may be fed, the Bureau of Animal Industry of the United States Department of Agriculture (Kutish 1950a) reports: At various times and under different circumstances, molasses products are fed to nearly all classes of animals. Larger proportionate amounts are generally fed to beef cattle than to poultry and swine. Generous amounts can be fed to horses, mules, sheep and goats. We have ordinarily advised use of 5 per cent of this feed. In the case of swine, 10 per cent can be used although we have fed 20 per cent in test rations. For cattle, a third or more of the corn or other grain can be replaced with molasses. Occasionally much larger amounts are used. Feeding carbohydrates in the form of sucrose for short periods before slaughtering improved the keeping quality, flavor and texture of pork as noted by Gibbons and Rose (1950) and Madsen (1950). These investigators indicated a need for further studies on swine and detailed studies on beef. The purpose of this investigation was to study the effect of feeding sucrose to beef and swine prior to slaughter, on the percentage of carbohydrate, pH, color, texture, and flavor of muscle and liver.
122

Effects of Beaver on Stream Flow and Water Quality

Bates, James W. 01 May 1963 (has links)
Water, one of the major resources of the western lands, controls the economy and expansion of the communities. Industry, agriculture, timber, livestock, game and home water needs are all dependent upon a steady and continued flow of water from wells, springs, and rivers. Water is derived from one source, precipitation, which occurs in the form of rain and snow. Watersheds which are properly managed accumulate a substantial snow pack during the winter which is the life-giving source of water for our springs. The Utah Water and Power Report (1948) indicates the annual precipitation over the entire state of Utah averaged 11.5 inches. A total of 53 ,000,000 acre-feet of water falls within the boundaries of the state of Utah each year, the amount varying with elevation and topography. The Bear River contributes an average of 725,000 acre-feet. A total of 2,334,000 acre-feet is carried away each year by streams leaving the state, leaving the net amount of 51 ,391,000 acre-feet to be consumed within the state. Water consumed on irrigated lands represents less than five percent of the total amount while evapotranspirational losses from the watersheds and grazing lands amount to almost 75 percent of the total water supply. Utah has approximately 1,500,000 acres of land suitable for agricultural production without a water supply; and of the 1,000,000 or more acres of irrigated land, only 25 percent has adequate and dependable supply of water. Droughty conditions and low water supplies are becoming more acute in the state of Utah each year, creating a need for water conservation.
123

“Development of Genetic and Genomic Predictors of Fertility in Argentinean Holstein Cattle.”

Di Croce, Fernando Alfonso 01 December 2010 (has links)
The overall aim of the studies described herein was to evaluate genetic variation in cattle fertility traits for development of genetic and genomic predictors in breeding strategies. Results from these experiments suggest that improvements in fertility through genetic selection are a possible approach to increase reproductive efficiency. Experiment 1 evaluated the development of genetic parameters associated with multiple ovulation and embryo transfer schemes in an attempt to assist producers in identifying animals with greater genetic merit for these protocols. This study confirmed that genetic selection of donors or sires appears to be a potential approach to improve efficiency of MOET procedures. Although low heritability would slow the progress, results shown in this work suggest that genetic improvement in fertility by selection for embryo transfer traits is possible. Experiment 2 evaluated fertility traits in Argentinean Holstein cattle in order to develop fertility genetic predictors for utilization in breeding strategies. The dollar fertility index ($F) included age to first calving (AFC) as a measure of initial reproductive performance and calving interval (CI) as an indicator of conception rate and success of early insemination. Values for $F ranged from -$76.6 to $139.4 in the current Holstein population. Results indicated substantial variation in fertility traits, suggesting that genetic selection would be highly effective in improving fertility.
124

Performance of Pre and Post-Partum Weather Stressed Cows Supplemented with Yeast Culture

Ortiz, Fabian 01 May 2006 (has links)
Livestock have been fed yeast as a feed supplement for more than 100 years Stone, C. 00). Yeast is a microscopic, single cell fungi of the plant kingdom. Of the 50,000 species of fungi, only 60 different genera of yeast representing about 500 different species exist. A few of these are used commercially in the animal feed industry as active dry yeast or yeast culture (Kreger, van Rij, 1984). Yeast culture consists of live yeast cells, plus the medium on which yeast is grown. Yeast products are commonly fed as pro-biotics, but little is known about their effects. Some studies have reported that yeast products increased milk yield and milk fat percentage; however, other studies found that yeast products had no effect on any of these factors (Middelveld. H 1998). A three phase trial, starting August 2003 and ending February 2005, was conducted at the Western Kentucky University Agricultural Research and Education Complex (Dairy facilities), in Bowling Green, Kentucky. Trial 1 evaluated the affect of dietary yeast, (WY) a, fed to cows in early lactation during heat stress conditions. Trial 2 evaluated the effect of dietary yeast WY fed to pre and post-partum cows during weather stress conditions. Trial 3 evaluated milk yield of cows fed post-partum cows 2 different types of yeast, (CC5)b or (YS)C, versus a no yeast control group (CG)d, during weather stress conditions to post-partum cows. Cows in trials 1 and 2 were fed a total mixed ration (TMRs) consisting of corn silage, alfalfa hay and haylage, grain mix, whole cottonseed and controlled access to alfalfa pasture; while the third trial cows received a TMR of corn silage, alfalfa hay, whole cottonseed and grain mix. In all trials, milk weights were captured and recorded at each milking using electronic weigh meters, which download into a computer. Seven day average milk weights were used for the analysis in all the trials. Data were analyzed using SPSS 13 and Microsoft Excel XP 2006, standard statistical analysis software. In trial one milk yield and energy corrected milk (ECM)were statistically higher (p<0.05) in the Holstein WY group. The limited Jersey sample size did not provide adequate statistical data for analysis. In the second trial, milk yield and ECM were statistically higher in the Jerseys in trial WY versus the Jerseys in the CG group. There was no significant statistical difference in Holsteins treated WY versus the Holsteins in the CG group. In the third trial, ECM was statistically significant at (p= 0.05) in the CC5 groups versus the CG group. The CC5 group differed from YS group at the (p= 0.05) level in the Holstein groups as well as in the Jersey groups. The statistical difference in ECM may be due to the different composition of the yeast used in the diet plus the stress caused by environment. The CC5 group and YS groups were statistically higher in average milk yield (p=0.05) han the CG group. A positive response on milk yield appears to be found in those groups feed yeast. Based on these completed trials, the usage of yeast has a moderate impact on milk production as well as milk composition. These heat and transition trials suggest positive economical returns based on ECM from the usage of yeast.
125

The Effect of Calf Morbidity on Feedlot Performance and Profitability

Gentry, Jessica 01 August 1998 (has links)
Two "Value-Added Calf (VAC) Programs were evaluated relative to feedlot performance and profitability. Two hundred seventy-three head of feeder calves were included in this study. Ninety-five Certified: Preconditioned for Health (CPH), ninety KCA Gold Tag and eighty-eight "Sale Barn" cattle were fed at Horton's Research Feedyard in Fort Lupton, Colorado. No background information regarding the health status of the Sale Barn cattle was known. Cattle were purchased in December 1997 and were entered in the Rocky Mountain Ranch-to-Rail program on January 6, 1998. The cattle were checked daily for illness and taken to a hospital pen for treatment if symptoms of Bovine Respiratory Disease (BRD) were observed. In addition, the cattle were weighed on January 6 and again on March 14 to measure performance parameters. Morbidity rates were 31.6%, 36.7% and 78.4% for the CPH, KCA Gold Tag and Sale Barn groups, respectively. When separated by the number of trips to the hospital pen (0= no trips, 1= one trip and 2+= two or more trips), 24.2% of CPH and 21.1% of KCA Gold Tag calves classified as sick, were treated only once for morbidity. Of the Sale Barn calves that were taken to the hospital pen, 66.7% were treated two or more Times. These cattle developed more serious cases of BRD and required additional medication beyond the antibiotic treatment. In addition, mortality rates were 0%, 1.1% and 10.2% for the CPH, KCA Gold Tag and Sale Barn groups, respectively. Calves sold as realizers because of chronic illness represented 1.0%, 0% and 10.2% of the CPH, KCA Gold Tag and Sale Barn groups, respectively. Least-squares means for all variables except average daily gain (ADG) and weight #2 (W2) were calculated by including all animals placed on feed in this study ("included" -1) and by excluding all dead and realizer cattle ("not included" - NI). Least-squares means for actual net return (ACTNET-I) were $-22.01, $-4.96 and $-50.18/hd for the CPH, KCA Gold Tag and Sale Barn groups, respectively. Applying equal purchase prices to the cattle and calculating net return (ADJNET-I), least-squares means were $-4.61, $-5.75 and $-68.17/hd for the CPH, KCA Gold Tag and Sale Barn groups, respectively. There was no significant difference in ADJNET-I for the CPH and KCA Gold Tag cattle; however, both of these groups had a significantly higher ADJNET than the Sale Barn cattle. MEDNET-I costs were $8.78, $9.30 and $10.95/hd for the CPH, KCA Gold Tag and Sale Barn calves, respectively. The Sale Barn group had the highest MEDNET-I (P < .05). Value of cattle was determined using Cattle-Fax feeder calf prices for the week of March 13, 1998, basis Colorado (week in which cattle were re-implanted, representing approximately 90 days of ownership). The CPH and KCA Gold Tag cattle had a higher VALUE-I ($/hd) than the Sale Barn cattle (P < .05). There was no statistical difference in average daily gain (ADG) among the groups. Least-squares means categorized by hospital designation indicated that calves from both hosp 0 and hosp 1 had in higher net returns than calves from hosp 2+ (P < .05). In addition, calves from hosp 0 or hosp 1 had a higher value than those calves treated two or more times (P < .05). ADG was significantly higher for calves designated as hosp 0 or hosp 1 than calves designated as hosp 2. Least-squares means relative to the VAC Program by hospital designation interaction showed that cattle that remained healthy during the feeding phase had positive values for net return, indicating a profit. Sale Barn cattle treated two or more times for BRD had the lowest net return and the highest medical costs (P < .05). ADJNET-NI for KCA Gold Tag and Sale Barn cattle increased with one trip to the hospital pen. In addition, ADG and W2 also increased for the hosp 1 group of KCA Gold Tag and Sale Barn cattle. This trend indicates that some cattle from these two treatment groups were not identified as "sick" in the feedyard and did not receive treatment for BRD. However, ADJNET-I and ADJNET-NI for the CPH cattle actually decreased with trips to the hospital pen. This decrease in net return for the hosp 1 and hosp 2+ groups indicates that sick cattle were treated accordingly in this pen. ADJNET-NI for CPH/hosp 2+ cattle was the lowest of all interactions (P < .05). The CPH cattle that remained healthy in this study were the most profitable and had the highest value when compared to the other groups. Results from this study indicate that VAC Programs did improve the health status of cattle. Both the CPH and KCA Gold Tag groups had higher average net returns when purchased at comparable prices, lower average net medical costs and lower morbidity and mortality rates when compared to the Sale Barn group. Results from this study support the theory that some vaccination against BRD is better than no vaccination at all. However, proper management prior to weaning and transport is the key to reducing stress and decreasing the incidence of BRD.
126

A Comparison of Pregnant Mare Serum Gonadotropin and P.G. 600® to Improve Reproductive Efficiency in Sows

Tate, Evan 01 August 2007 (has links)
Three hundred and nineteen sows were utilized to study the effects of pregnant mare serum and P.G 600 on reproductive efficiency. Sows were randomly allotted to treatments. Sows were evaluated for age (# of parities), breed composition and body condition score. Three sows who shared all three fields in common were randomly treated with one of three treatments the morning after weaning: 1. (S) Controls: 5ml of Sterile Saline Solution 0.9% 2. (M) Treatment (PMSG): 12ml of Pregnant Mare Serum 3. (P) Treatment (PG600)® 5ml of P.G. 600 (Intervet America Inc., Millsboro, DE) No differences were observed for total number of pigs born among treatments (P>.05). Neither parity, body condition or breed composition had a significant influence on total number born. However, treatments of pregnant mare serum and P.G. 600 to controls resulted in significantly shorter wean to estrus intervals (P<.0002 vs. P<.0001) than sows in the control group respectively) from weaning to estrus. Additionally, P.G. 600 treated sows had shorter weaning to estrus intervals than PMSG treated sows (P<.0802).
127

Relationships of Body Condition, Blood Glucose and Insulin Concentration of Grazing Horses

Montfort, Ashley 01 May 2007 (has links)
A recent study has reported that blood glucose levels and founder in horses consuming forage/concentrate mixed diets are positively correlated (Pass et al., 1998). Other studies have reported body fat and insulin resistance are also positively correlated in horses and humans (Hoffman et al., 2003; Boshell et al., 1968; DeFonzo et al, 1991; Kahn et al., 2000). Few studies have monitored these relationships in horses consuming forage only diets, even though the incidence of grass founder is quite high in obese horses and ponies Four thin, four moderate, and four obese horses were grouped two mares and two geldings per group in a completely randomized design. They were allowed six months to adapt to an all forage diet consisting of free choice access to a mixed grass pasture. The pasture consisted of primarily Fescue with limited additional quantities of Bermuda Grass and Blue Grass. Following the adaptation period, blood samples were collected at four hour intervals, during a twelve-hour grazing period to determine effects of body condition, sex, and time of sampling on blood insulin and glucose concentration. Blood glucose analysis was done utilizing the Ultrasmart monitor. Accuracy verification was obtained by dual sample analysis with the Vetest 8008 animal glucose monitor. Results indicate the Ultrasmart monitor is a highly accurate and effective method of analyzing blood glucose concentrations in the horse. No significant blood glucose variation due to time of sampling, sex, or body condition was observed. Sex of animal and time of sampling had no significant effect on circulating insulin concentration. Mean blood glucose concentration for all horses consuming the pasture diet was 77 mg/dl. Results also indicated that the mean normal blood glucose concentration of horses consuming this grass pasture diet was similar to the mean of 74.7mg/dl reported for horses consuming forage/concentrate mixed diets (Williams et al., 2001). Blood insulin concentrations of the moderate horses were not different from those of the thin or fat horses. They were however significantly lower, in the thin horses than the obese horses. Therefore, fatter horses secreted greater quantities of insulin while maintaining normal blood glucose levels. In a second study, Glycosylated Hemoglobin (HBAlc) measurements of the aforementioned horses using a human blood meter was attempted. The technique was not effective for measuring horse blood and was abandoned. Further research in this area may provide an effective mechanism for evaluating long term blood glucose and insulin chemistry.
128

The Environmental Factors Regulating the Distribution of Crayfish in the Upper Green River Basin Kentucky, USA

Ngulo, Eva 01 December 2007 (has links)
Despite the importance of crayfish in aquatic systems there are major issues threatening their conservation, including invasive species, habitat alterations, and species with small distributions or have limited geographical ranges. There is limited information regarding native range, habitat requirements, life histories and biological interactions between crayfish species. In order to examine the relationship between lotic crayfish assemblages and environmental variables at both the watershed and reach scales, data were collected from 46 stream segments in the Upper Green River Basin of Kentucky, U.S.A. An independent sample t-test compared crayfish densities between segments with gravel - small cobble, and large cobble - small boulder substrates and revealed non-significant differences for both all and large (>15 mm) carapace length individuals. Correspondence analyses were conducted separately for gravel-cobble and cobble-small boulder segments and large boulder segments and some species showed strong associations with each other. In the gravel-cobble/cobble-small boulder segments a series of one-way ANOVA's showed significant effects of sub-basin location on both crayfish density and species richness whereas in the large boulder segment there were no significant differences. An exploratory canonical correspondence analysis in the forward selection procedure was performed to reduce the number of environmental variables in the gravel-cobble/cobble-small boulder segments and large boulder segments. The second CCA performed between crayfish species and environmental variables showed relationships with several environmental variables in the gravel-cobble/cobble-small boulder segments. Significant variables elucidated were summer mean temperature, depth, and total phosphate. The second CCA in the large boulder segment, however, failed to find strong relationships between the crayfish and environmental variables. Further testing using multiple linear regression stepwise forward selection analysis demonstrated that crayfish were responding to total phosphorous, % riffle, %run, gravel, cobble, boulder, total phosphorous and ammonia in the gravel-cobble/cobble-small boulder segments. The results indicated that stream size gradient and not % land use were linearly related to both diversity (richness) and density.
129

Effects of Training and Experience on Repeatable and Reliable Assessment of Beef Cattle Body Condition Scores

Burmeister, Pete 01 December 2006 (has links)
In recent years, body condition scores (BCS) have been included in Expected Progeny differences (EPD) calculations for maintenance energy. This experiment was designed to identify the acuteness at which technicians of different skill levels can correctly quantify BCS in beef cattle. Thirteen students enrolled in agriculture at Western Kentucky University were assigned to three experimental technician groups based on training level. Five members of the colligate livestock judging team with extensive cattle backgrounds were BCS trained and assigned to the experienced level, four students were BCS trained by the WKU livestock judging coach and assigned to the trained level, and four students with no training were assigned to the untrained group. All students were given a seminar covering body condition scoring and provided a supplemental handout on body condition scoring to use as cows were evaluated. One hundred forty-four beef cows were allotted into two experimental groups based upon breed. One group consisted of 49 Simmental cows; the other group consisted of 95 Angus cows. Coefficients of Correlation for the "equal number in all BCS" analysis were 0.62, 0.54, 0.53, and 0.93 for experienced, trained, untrained, and the official groups; respectively. Coefficients of Determination for the "equal number in all BCS" analysis were 39%, 39%, 28%, and 86% for the experienced, trained, untrained, and the official groups; respectively. The average Standard Error of Difference for the "equal numbers in all BCS" analysis were 0.451, 0.459, 0.518, and 0.301 for the experienced, trained, untrained, and the official groups, respectively. The average standard Error of Prediction from the official score for the "equal numbers in all BCS" analysis were 0.583, 0.612, and 0.618 for the experienced, trained, and untrained groups, respectively. Level of experience was significantly different (P<0.0001) between experienced and untrained technicians as well as trained and untrained technicians. There was no significant (P>0.50) difference between experienced and trained. Results from this trial indicate a need for extensive training to obtain accurate and reliable body condition scores on beef cattle.
130

Strategies for Reducing Mosquito-Borne Disease Vulnerability in Equine Populations: A Kentucky Case Study

Dalton, Sara 01 August 2006 (has links)
This research examined equine management practices that limit or contribute to the spread of West Nile virus and other mosquito-bome disease. I hypothesize that there is a relationship between equine management practices and outbreaks of mosquito-borne disease in horse populations. Improved and appropriate mosquito habitat management may limit the risk of mosquito-borne disease in humans and horses by helping to lower the mosquito populations. The study goals were to recognize equine management practices and mosquito prevention practices that foster outbreaks of mosquito-borne disease. This study used a questionnaire for county level analysis of equine management practices and the relationship to mosquito-borne disease. This study is important because horses live in a natural setting among unmanaged elements, such as pastures with ponds, wooded areas, and riparian areas. However, horses themselves are highly managed. Equine management practices include pasture horses, who live exclusively outdoors, stabled horses who receive some turn-out time, and ultra-managed horses, such as race horses. Kentucky's economy is partially dependant on the horse industry, which is responsible for over 51,000 jobs and is a major part of the culture of Kentucky. Equine diseases can significantly affect this section of the state's economy. The study area consisted of three categories of noncontiguous counties, with each group containing three to four Kentucky counties. The three selected categories of study highlighted areas of West Nile virus incidence in equine populations. Surveys were distributed to horse owners and barn managers to collect data on differences in equine management practices and outbreaks of mosquito-borne disease. Two categories represented counties with large equine populations, and one category represented counties with low equine populations. Category I consists of the three counties that were selected based on high horse populations and high incidence of West Nile virus in 2002—Barren, Fleming, and Nelson counties. Category II consists of four counties with high equine populations and low incidence of West Nile virus in 2002 - Allen, Grant, Jessamine, and Meade counties. The third category looks at low equine populations and high incidence of West Nile virus in 2002 - Carlisle, Marion, Russell, and Todd counties. Areas with low equine populations and low incidence of West Nile virus were not considered for the study because those areas do not have either high horse populations or high incidence of West Nile virus and hence were not relevant for this particular research question about equine management practices. A minimum of thirty surveys was collected for each category. Statistical analysis was used to determine relationships between incidences of disease, management practices, and knowledge of mosquito prevention. Each survey question was analyzed using the two-tailed version of the two-sample difference of proportion test. West Nile virus is an important disease to study due to the potential economic loss to the horse industry but also because the disease has been responsible for sickness and death in human and animal populations. I studied horses because of the their mix of unmanaged and managed habitat. This study did find a difference in equine management practices when it came to vaccination to prevent West Nile virus occurrences in horse populations. Horse people in categories with high horse populations had a higher use of a West Nile virus vaccine to prevent disease than people use in the low horse population category. While statistics from this study show that there is little or no difference in other equine management practices between the three categories, this research demonstrates that few horse owners and barn mangers limit mosquito habitat around their animals or are aware of IPM techniques. Vaccination lowers the chance that a horse will develop West Nile virus, but it is important that active equine management programs include limiting mosquito habitat to assist in prevention of mosquito-borne disease. Limiting mosquito-borne disease is an important preventive strategy that could protect the health of both horses and humans.

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