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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.
151

Analysis of Single Nucleotide Polymorphism Panels for Bovine DNA Identification

Blanchard, Kimberly A. 01 May 2013 (has links)
Single nucleotide polymorphisms (SNPs) are single base-pair variations that exist between individuals. There are approximately a million or more SNPs located throughout the genome of each individual animal. Therefore, by taking advantage of these unique polymorphisms, SNPs can be used to resolve questions of unknown parentage in the livestock industry. Currently a panel of 88 SNPs, obtained from a panel of 121 SNPs originally created by USDA-MARC, is commercially available from Fluidigm®. The objective of this study was to determine whether the number of SNPs from the 88-SNP marker panel could be reduced to form a smaller, more cost-efficient parentage-testing SNP panel. A smaller panel would benefit farmers and researchers alike in reducing the time spent in running and analyzing the test, as well as reducing the overall cost for the procedure. Genotype data from over 3000 cattle samples containing offspring and potential parents were examined using two parentage calling software packages. Parentage assessment was analyzed using nine SNP panels of varying size. It was determined that a panel of 71 SNPs, chosen from the original 88 SNPs, was the minimum number required to maintain statistical accuracy and reliability.
152

Production and Intake Responses of Dairy Cows Fed Four Levels of Malic Acid

Martinez Alferez, Juan Carlos 01 May 1978 (has links)
Thirty-two lactating cows were assigned at random to four treatments of malic acid to determine if these levels had an effect on milk production, milk composition, feed intake, and efficiency of feed utilization. Malic acid allotment for each treatment consisted of 1) 15.4, 2) 11.6, 3) 7.7, and 4) 0 grams of malic acid fed per kilogram of concentrate. Concentrate was fed according to production at a rate of one kilogram per two kilograms of milk in excess of 9.1 kilograms of milk per cow daily. Alfalfa hay was fed free choice and corn silage at a rate of 11.4 kilograms daily. The cows were on the trial for 8 weeks. Intake of concentrates, silage, dry matter, and digestible energy was highest for cows receiving the 11.6 g level of malic acid. These intakes were significantly higher than for the 7.7 g level but not for the other treatments. However, cows on the 7.7 g level consumed only slightly less feed than control cows. There was no significant effect on hay or crude protein intake. Production of total milk, fat corrected milk, and milk fat was significantly higher for cows receiving the 11.6 g level of malic acid than from the 7.7 g level or control cows. Production of protein solids-not-fat was significantly higher for the 11.6 g level than from the 7.7 g level and approached this level of significance when the 11.6 g level was compared to the controls. Cows receiving the 11.6 g level of malic acid were significantly more efficient in converting dry matter or digestible energy from feed into milk than were the controls. Intakes and production of cows on the 15.4 g level was slightly less than for the 11.6 g level.
153

Use of Corn Syrup Solids of Different Dextrose Equivalents in the Manufacture of Frozen Desserts

Axelgard, Wiggo F. 01 May 1954 (has links)
Importance of problem: The ice cream industry continually faces the problem of improving its frozen desserts. At the present time corn syrup solids are being used to supplement milk serum solids to improve the body and texture of these products. One of the problems is to increase the total solids content of frozen desserts without increasing sweetness or developing sandiness in the finished product. There is a limit to the amount of milk serum solids that can be used because of the danger of sandiness and the cost . The use of corn syrup solids helps to overcome these limiting factors. The corn syrup solids product now used contains a dextrose equivalent of 42. The corn products manufacturers are beginning to make a product with different dextrose equivalents with different degrees of sweetness. Modifications of DE 42 contain dextrose equivalents of 24 and 31 and will add corn syrup solids of different dextrose equivalents or degrees of sweetness to these frozen desserts. Robert L. Lloyd defines dextrose equivalent as follows: The percentage of reducing sugars present on a dry basis indicates the degree to which conversion has been carried in the hydrolysis of starch. Dextrose has a DE of 100 and is used as the standard. The lower the dextrose equivalent of a product the less the sweetening power. Purpose of problem: 1. To determine the optimun amounts of corn syrup solids to use in building body and texture in frozen desserts without impairing flavor. 2. To determine the comparative value of different amounts of DE 31, DE 24, and DE42.
154

Trichomoniasis of the Utah Agricultural Experiment Station Dairy Herd

Jensen, Rue 01 May 1939 (has links)
Bovine trichomoniasis is a venereal infection that reduces the fecundity of cattle. It is caused by Trichomonas foetus, a flagellated protozoan which inhabits the genital tract, causing inflammation and partial sterility. Both sexes are susceptible to infection. In females it is usually of short duration and frequently terminates sponaneously following abortion. In males the disease has both acute and chronic stages. During the acute stage the prepucial membranes become inflamed and a muco-purulent discharge develps in which trichomonads are abundant. In the following chronic stage symptoms disappear, but the animal remains a carrier and is a dangerous source of infection to healthy cows. Diagnosis is made by examining the material from infect organs for the specific parasite. The cell body of Trichomonas foetus is fusiform or napiform. It varies from 9 to 20 microns in length, and from 3 to 7 microns in width. Its salient features are an undulating membrane and 4 flagella arising from the blepharoplast, 3 of which are anterior and free, the fourth proceeds caudad bordering the undulating membrane for its entire length and projecting unattached behind. By means of the flagella and undulating membrane the organism move jerkily through an irregular course, as is characteristic of the genus Trichomonas. Dovine trichomoniasis has a wide geographic distribution. In Europe it has been reported from Italy, France, Germany, Holland, and England. Futamura has reported it from Japan. In the United States the infection is known to be present in the states of New York, Pennsylvania, Iowa, Illinois, Maryland, Texas, Michigan, California, and Utah. Survey work done in Utah under the direction of the Utah Agricultural Experiment Station includes examination of herds in Cache, Utah, Davis, Sanpete, and Sevier Counties. Infections were found present in all counties where examinations were made except Sevier. Because of unrestricted commerce of cattle among the important live-stock centers, it is supposed that trichomoniasis is widely spread and probably exists in some cattle in the majority of the counties of the state.
155

Domestication effects on the human-chicken relationship

Demree, Ruth January 2023 (has links)
Domesticated species possess certain cognitive abilities that allow them to thrive in an environment with regular human interaction, and these interactions contribute to the overall human-animal relationship. Studying the human-animal relationship allows us to better understand how domesticated animals perceive and navigate their environment, which can then be used to improve their welfare. In chickens, this relationship is poorly understood, and further research would provide insight into the welfare needs of this animal. Here we show breed differences in the interspecific sociocognitive abilities of Gallus gallus, where the domesticated White Leghorn interacted more with a familiar human than the red junglefowl, and both the domesticated White Leghorn and the red junglefowl breed that had been selected for low fear of humans were habituated to human presence. This study sheds light on the effect of domestication on social cognition in chickens and begins to describe the human-chicken relationship.
156

Studying Milk Coagulation Kinetics with Laser Scanning Confocal Microscopy, Image Processing, and Computational Modeling

Hennessy, Richard Joseph 01 June 2011 (has links) (PDF)
The kinetics of milk coagulation are complex and still not well understood. A deeper understanding of coagulation and the impact of the relevant factors would aid in both cheese manufacturing and also in determining the nutritional benefits of dairy products. A method using confocal microscopy was developed to follow the movement of milk fat globules and the formation of a milk protein network during the enzyme-induced coagulation of milk. Image processing methods were then used to quantify the rate of coagulation. It was found that the texture of the protein network is an indicator of the current status of the milk gelation, and hence can be used to monitor the coagulation process. The imaging experiment was performed on milk gels with different concentrations of the coagulation enzyme, chymosin. Rheological measurements were taken using free oscillation rheometry to validate the imaging results. Both methods showed an inverse relationship between rennet concentration and the coagulation time. The results from the imaging study were used to create a computational model, which created simulated images of coagulating milk. The simulated images were then analyzed using the same image analysis algorithm. The temporal protein network texture behavior in the simulated images followed the same pattern as the protein texture in the confocal imaging data. The model was developed with temperature and rennet concentration as user inputs so that it could be implemented as a predictive tool for milk coagulation.
157

Comparison of Foaming Properties Between Chelated Reconstituted SMP and Caseinates

Liu, Boya 01 June 2016 (has links) (PDF)
Caseinate powders have been well accepted because of their foaming properties. In this study, 10% solution of reconstituted skim milk powder (SMP) chelated with sodium hexametaphosphate (SHMP) and trisodium citrate (TSC) at 1 mEq, 50 mEq, and 100 mEq were prepared to conduct a comparison with sodium caseinate, potassium caseinate, and calcium caseinate solutions. Foamability, foam stability as well as the preferential locations of αs-casein, β-casein and !-casein in their foams were analyzed. It was hypothesized that the foamability, foam stability and the preferential locations of these three caseins in the milk foams are different from treatment to treatment. Milk foam was generated with an air- injection method at a flow rate of 0.30 L/M for 18 seconds. Foam stability was measured through half-life method. The foam composition was quantified with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method. Analysis of Variance (ANOVA) test results concluded that there were no significant differences detected in foamability (p>0.05). On the other hand, foam stability differed significantly among the treatments. Foams of reconstituted SMP-treated with 1 mEq SHMP and TSC were significantly more stable compared to other treatments (p < 0.05), β-casein (p>0.05) and !-casein (p>0.05). In conclusion, the addition of calcium chelating salts might increase the foamability to the same level as caseinate solutions. Furthermore, the study proved that the combination of calcium chelating salts and chelator levels is able to alter the foam stability.
158

The Effects of Providing Social and Nutritional Enrichment to Dairy Calves on Development, Behavior and Learning

Kutina, Kendra Leigh 01 June 2019 (has links) (PDF)
The objective of this study was to measure the effects of both a nutritional (water nipple) and social (partner calf) enrichment on calf body weight, grain intake, water intake, behavior and learning. The enrichments included 1) water provided from a nipple vs. a bucket (nutritional) and 2) visual and tactile access to a partner vs. isolated rearing with no visual or tactile access to a partner calf (social). A total of 72 Holstein and Jersey dairy calves were pseudo-randomly distributed into 4 treatments at birth [Individual/Bucket (IB), Paired/Bucket (PB), Individual/Nipple (IN), Paired/Nipple (PN)]. Socially and nutritionally enriched calves drank more water than non-enriched calves (Social: 5.02 ± 0.27 kg/d vs 3.723 ± 0.27 kg/d respectively; P = 0.0009; Nutritional: 4.93 ± 0.27 kg/d vs. 3.81 ± 0.26 kg/d respectively; P = 0.004). No difference in daily grain intake was found between individual or pair reared calves except during wk 8 (1.31 ± 0.07 kg/d vs 1.60 ± 0.07 respectively kg/d; P= 0.04). There were no differences in average body weight among treatments (P > 0.20). Pre-milk delivery, calves reared on a water bucket spent more time standing (P= 0.03) and when paired, less time non-nutritively suckling compared to water nipple reared calves (P = 0.05). Grooming time was highest during period 2 (wk 3, 4, 5; P = 0.01)) pre-milk delivery. Post-milk delivery, calves reared on a water bucket spent more time drinking milk (7.13 ± 0.40 vs 5.37 ± 0.39 min; P = 0.005)and grooming (P= 0.05), and less time drinking water (P < 0.001)and lying (6.17 ± 1.02 vs 9.19 ± 0.97 min, respectively; P= 0.04)than water nipple reared calves. Water nipple calves when paired exhbited longer drinking times (P = 0.04)..The most notable behavior was cross suckling post-milk delivery, as the weeks progressed water bucket reared calves increased time spent cross-suckling while water nipple calves maintained the amount of time spent cross-suckling. At wk 8 a subset of 24 calves (6 from each treatment) were trained over 14-d period to differentiate between an “X” and “O” cue to receive a milk reward (visual discrimination task). Learning (% correct choices) was compared using a Wilcoxon-signed rank test. Calves individually reared had greater overall correct choices than pair reared calves (0.63 ± 0.02 % correct/total choices vs 0.57 ± 0.02 % correct/total choices respectively: P = 0.05), while calves reared with a nutritional enrichment (water nipple) had greater overall correct choices compared to water bucket reared calves (0.64 ± 0.02 % vs 0.56 ± 0.02 %, P = 0.02). These results indicate that social and nutritional enrichments positively influence calf cognitive performance, water intake, and lying, cross-sucking, grooming behaviors.
159

Agronomic performance and beef cattle grazing preference among three prairie bromegrasses

Hubbard, Allen Stewart 15 December 2007 (has links)
Prairie bromegrass is a cool-season perennial bunchgrass with potential as a valuable forage crop in the southeastern USA. The objective of this study was to compare dry matter production, persistence, nutritive value, and beef cattle grazing preference of two experimental lines and a commercial species (cv. Matua) of prairie bromegrass. Plots were established in a randomized complete block design with four replications. When each plot accumulated at least 20 cm of growth, plots were grazed with Hereford x Angus steers at a stocking rate of 8400 kg/ha until the first plot was grazed down to 7 cm in height. Pre- and post-grazing quadrats were taken for DM and animal preference estimation and nutrient analyses. No differences in nutritive value or grazing preference were seen among species. Treatment interactions were observed for DM production and persistence. The results suggest that there are differences in growth traits among the bromegrass species observed.
160

INCORPORATING MACHINE VISION IN PRECISION DAIRY FARMING TECHNOLOGIES

Shelley, Anthony N. 01 January 2016 (has links)
The inclusion of precision dairy farming technologies in dairy operations is an area of increasing research and industry direction. Machine vision based systems are suitable for the dairy environment as they do not inhibit workflow, are capable of continuous operation, and can be fully automated. The research of this dissertation developed and tested 3 machine vision based precision dairy farming technologies tailored to the latest generation of RGB+D cameras. The first system focused on testing various imaging approaches for the potential use of machine vision for automated dairy cow feed intake monitoring. The second system focused on monitoring the gradual change in body condition score (BCS) for 116 cows over a nearly 7 month period. Several proposed automated BCS systems have been previously developed by researchers, but none have monitored the gradual change in BCS for a duration of this magnitude. These gradual changes infer a great deal of beneficial and immediate information on the health condition of every individual cow being monitored. The third system focused on automated dairy cow feature detection using Haar cascade classifiers to detect anatomical features. These features included the tailhead, hips, and rear regions of the cow body. The features chosen were done so in order to aid machine vision applications in determining if and where a cow is present in an image or video frame. Once the cow has been detected, it must then be automatically identified in order to keep the system fully automated, which was also studied in a machine vision based approach in this research as a complimentary aspect to incorporate along with cow detection. Such systems have the potential to catch poor health conditions developing early on, aid in balancing the diet of the individual cow, and help farm management to better facilitate resources, monetary and otherwise, in an appropriate and efficient manner. Several different applications of this research are also discussed along with future directions for research, including the potential for additional automated precision dairy farming technologies, integrating many of these technologies into a unified system, and the use of alternative, potentially more robust machine vision cameras.

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