M. S.

Dilated cardiomyopathy (DCM), a disease of the myocardium, causes morbidity and premature death in humans and other domestic animals including turkeys. Though DCM results from many different factors including those that are unknown or idiopathic, genetic factor is a major cause of idiopathic DCM. In this study, I assessed the molecular basis of toxin-induced DCM in turkeys by evaluating the association and effect of mutations in candidate genes in the nucleus and mitochondria on the incidence and severity of this disease. Echocardiographic measurements at 3 weeks of age showed that birds on furazolidone-containing diet exhibited a significant DCM phenotype (increased left ventricular end diastolic dimension and left ventricular end systolic dimension) with a marked decrease in the left ventricular shortening fraction. Pathological phenotype confirmed the dilated heart with extended cell necrosis. Two mutations, both in NADH dehydrogenase genes, were found to be associated with DCM. Real-time RT-PCR quantification indicated that mRNA expression of alpha cardiac actin gene (ACTC) were significantly different between control and treatment birds. While ACTC expression increased, though moderately, in control birds from week 1 to 3, it decreased significantly in treatment birds. These findings suggest that the mitochondrial DNA variation and ACTC expression may be associated with the turkey's response to toxin. Therefore, further research is needed to investigate the molecular mechanism of toxin-induced DCM in the turkey. / Master of Science

Dilated cardiomyopathy (DCM), a heart disease, affects many vertebrates including humans and poultry. The disease can be either idiopathic (IDCM) or toxin-induced. Idiopathic DCM often occurs without a consensus cause. Though genetic and other studies of IDCM are extensive, the specific etiology of toxin-induced is still unknown. Here, our objective was to compare the level of mRNA expression of two candidate genes including troponin T (cTnT) and phospholamban (PLN) using quantitative reverse transcription polymerase chain reaction (RT-PCR) in toxin-induced DCM affected and unaffected turkeys. Cardiac TnT and PLN were chosen because their spontaneous expression has been reported to be associated with IDCM. We also scanned these genes for single nucleotide polymorphisms (SNPs) that could be useful in evaluating their functions in the incidence and severity of toxin-induced DCM in turkeys. There were no significant differences between affected and unaffected birds in the expression of both cTnT and PLN. A total of 12 SNPs were detected in cTnT and PLN DNA sequences. One of the seven haplotypes detected in cTnT was the most frequent. Linkage analysis showed that cTnT gene was unlinked on the current turkey genetic map. Resources developed here, including SNPs, haplotypes, cDNA sequences, and the PCR-RFLP genotype procedure will be used for future investigations involving cTnT and PLN and toxin-induced DCM. / Master of Science

Two experiments were conducted to quantitate the effects of several parameters on the growth, carcass characteristics and fat deposition of the turkey. In the first experiment, 0, 5, 10 or 15% fat from three sources (Fat 1, Fat 2 or Fat 3) was added to low (18%), standard (21%) or high (24%) protein diets fed to Nicholas Large White male turkeys from 8 to 22 weeks of age. Carcass quality as measured by fat deposition, carcass yield and breast meat yield was determined. The addition of each 1% added fat up to 10% increased body weight gain .72%. Feed consumption decreased 1.3% and feed efficiency increased 2.3% for each 1% added fat up to 15%. Addition of Fat 2 to the diet resulted in significantly better feed efficiencies as compared with Fat 1 or Fat 3. The feeding of low protein diets as compared with standard protein diets decreased body weight gain, feed consumption and feed efficiency 13.2, 5.7 and 8.1%, respectively. Addition of fat to the diet increased 22-week body weight and the amount of breast meat produced per kg feed consumed. For each 1% added fat to low and standard protein diets, leaf and gizzard fat deposition increased 10.2 and 8.0%, respectively. Feeding low protein diets resulted in a 10.4% decrease in body weight and a 19.5% decrease in breast meat yield. The increase in leaf and gizzard fat deposition from each 5% increment of added fat up to 10% was counteracted by a 3% increase in dietary protein. In the second experiment, both sexes of the Nicholas Large White, Jaindl Large White and Jaindl Medium White strains were fed standard (21%) or high (24%) protein diets containing 0, 5 or 10% added dietary fat from 8 to 28 weeks of age. Carcass quality as measured by yield of carcass parts, fat deposition and the composition of breast meat was determined at 16, 20, 24 and 28 weeks of age. The Nicholas strain of turkey had a greater growth rate and consumed less feed to reach heavier weights than the Jaindl Large strain. Addition of 10% fat to the diet decreased feed consumption 12% and increased feed efficiency 17%. Fresh carcass and breast meat yield increased with age of the turkey, indicating that marketing at younger ages does not take full advantage of the meat producing capability of the turkey. The Jaindl Large and Medium White strains averaged 6.8 and 6.9% more breast meat yield than the Nicholas strain. The Nicholas strain deposited 4.36 times more leaf fat and 1.84 times more lipid within the breast meat as compared to the Jaindl Large strain. Added dietary fat decreased fresh carcass yield .41% and breast meat yield .65%. Feeding high protein diets increased fresh carcass yield and breast meat yield .25 and .47%, respectively. / Ph. D. / incomplete_metadata

Like most agricultural production systems, effective decision making in turkey production systems requires the prediction of future status of the system and evaluation of alternative management policies. A simulation model of a turkey production system was developed to predict values of flock performance indicators of significant economic importance, namely body weight and feed consumption. Existing weather simulation models were combined and modified in order to develop a model that predicted daily dry-bulb temperature and humidity ratio outside the turkey house. The weather simulation model was validated using twenty years of daily observed weather data from Roanoke, Virginia. Thermal environment inside the turkey house was predicted from simulated outdoor weather using energy and mass balance equations. House environment prediction part of the model was validated using observed inside and outside temperature data collected at a turkey farm in Virginia. A discrete event simulation model was developed to simulate the effects of house thermal environment, feed energy, sex, and age on weight gain and feed consumption of growing turkeys. The model was validated using temperature, body weight, and feed consumption data collected at a turkey farm in Virginia. The observed average bird weights at marketing age were within 95% confidence intervals of the predicted values. However, the model underpredicted energy consumption values. The sensitivity of the model to variations in R-value, ventilation rate, and feed energy concentration was evaluated. The model was more sensitive to feed energy concentration. / Ph. D.

Four experiments were conducted on hens of turkey and Japanese quail. In Experiment I, turkey hens were fed diets containing either 0% added fat, 3.5% animal-vegetable fat blend (AV) or 3.5% dry fat product (DF). In Experiment II with turkey hens, 2 holding diets and 4 breeder diets were investigated. The holding diets contained either 0% added fat or 5% of AV. The breeder diets contained 0% added fat of 5% of one of the following: AV, corn oil (CO) or olive oil (OO). In Experiment III with Japanese quail, 3 pre-breeder (PB) and 3 breeder diets (BD) were studied. They contained either 0, 3.5 or 7% added AV. In Experiment IV with Japanese quail, all diets contained 97% of a semi-purified basal diet and 3% of one of the following: corn starch (CS), corn oil (CO), palmitic acid (PA), oleic acid (OA), linoleic acid (LA) or linolenic acid (LN). The fatty acid composition of plasma and yolk lipids of both turkeys and quail was influenced by the fatty acid composition of the diets. Quail fed a CO diet deposited more linoleic acid in the egg than did those on a LA diet. (Abstract shortened by UMI.)

No description available.

The aim of the thesis was to evaluate the feeding parameters of hybrid B.U.T. 6 at selected farm. Six batches of tom turkeys were evaluated in this study. The growth intensity analysis was performed based on weekly weighing. The average live weight was 21.83 kg at the age of 21 weeks. The highest value was in the 3rd batch (22.18 kg) and the lowest value was in the 2nd and the 6th batch (21.62 kg). In comparison with the "Management guide", the differences in average weight from the 5th week of age to the end of fattening were evaluated as statistically significant. The average feed conversion ratio was registered 2.73 kg. The highest feed conversion was in the 1st batch (2.82 kg) and the lowest was in the 5th batch (2.62 kg). The average inflection point was reached in the 14th week (12.1 kg). First the inflection point was achieved in the 1st and 2nd batch (13.6 weeks; 11.7 kg and 13.7 weeks; 11.4 kg) and at the latest in the 4th batch (15.5 weeks; 13.6 kg). The average maximum daily gain was reached 203.1 g (13.6 weeks). The highest was in the 3rd batch (204.9 g; 13.6 weeks) and the lowest was in the 4th batch (195.3 g; 14.3 weeks). The average mortality rate was found 6.39%. The highest mortality rate was in the 6th batch (8.44%; 858 pcs) and the lowest was in the 4th batch (4.50%; 457 pcs).

Turkey raising has become big business. During the period 1942 to 1946, the average annual return in Utah amounted to about nine and one half million dollars (4). This amount would have been increased considerably if the death loss among poults had been lower. As an example, using the percentages of mortality given by Miner (9, P. 5), it is estimated that the death-loss of turkeys in 1944 resulted in a loss of gross income by the farmers of Utah of more than four million dollars provided that the price the farmer received had remained the same.

Studies investigating the effects of feeding diets containing the yeast, Saccharomyces cerevisiae var. boulardii (SCB), and a yeast culture (YC) containing S. cerevisiae were conducted in market turkeys and Medium White turkey breeder hens. Increased utilization of dietary gross energy, N, Ca, P, B, K, Mg, and Mn were observed in poults fed a diet containing 1% YC when compared to the control and 1% inactivated YC diets at 4 weeks of age (WOA). It was concluded that the YC must be "biologically active" in order to affect nutrient retention in poults. Feeding day-old poults diets containing varying amounts of SCB resulted in increased body weights at 3 WOA. Greater body weights and a decrease in the number of mucous-secreting goblet cells per mm of villus height and a decreased crypt depth were observed in poults receiving .02% SCB from 3 to 5 WOA. No dietary differences were observed for either villus height or width. Results indicated that feeding SCB to poults increased body weight and altered gut morphology. Experiments conducted to evaluate the effects of .25% YC on market male turkey performance resulted in contradictory responses. Supplemental YC increased body weights of turkeys at 5, 8, 11, and 14 WOA in one trial, while no differences and depressed body weights from 2 through 17 WOA were observed in two subsequent trials, respectively. Similarly, feed to gain ratios were improved from day-old to 5 WOA in one trial, while no differences and a higher feed to gain ratio was observed from 2 to 5 WOA in the second and third trials, respectively. Results indicated that unelucidated factors may influence the response of market male turkeys fed dietary YC. Consistent results have been observed in two trials on the hatchability of fertile eggs (HFE) from hens of three genetic lines fed .5% dietary YC. Early embryonic mortality (0-10 d of incubation) was reduced when hens were supplemented with YC and the HFE was increased in eggs stored less than 9 days in select hen genotypes. Results indicated that the breeder hen's genotype and pre-incubation storage time are factors to be considered when evaluating a YC in turkey breeder hen diets. / Graduation date: 1994