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Articles 1201 - 1230 of 1242
Full-Text Articles in Animal Sciences
Relationships Among Herd Life, Milk Production, And Calving Interval, Paul Miller, L. Dale Van Vleck, C. R. Henderson
Relationships Among Herd Life, Milk Production, And Calving Interval, Paul Miller, L. Dale Van Vleck, C. R. Henderson
Department of Animal Science: Faculty Publications
Whether to select for longer life in the herd or shorter calving interval depends on the genetic and phenotypic relationships among herd life, amount of milk in first lactation, and calving interval. Herd life and average calving interval are essentially phenotypically uncorrelated. The phenotypic and genetic correlations of herd life and milk in first lactation ranged from .19 to .25 and from .54 to .77, respectively. The phenotypic correlation of average calving interval and milk in first lactation ranged from .19 to .21. Estimates of the heritability of herd life ranged from .05 to .14. This heritability was reduced by …
Plant Vs. Animal Protein As A Source Of Supplemental Protein For The Gilt, Dwane R. Zimmerman, E. R. Peo, Jr., D. B. Hudman
Plant Vs. Animal Protein As A Source Of Supplemental Protein For The Gilt, Dwane R. Zimmerman, E. R. Peo, Jr., D. B. Hudman
Department of Animal Science: Faculty Publications
Protein of animal origin has frequently been suggested to have greater nutritional value for swine reproduction than protein of plant origin. Moustgaard (1952) reported that gilts fed a diet in which the supplemental protein was of animal origin (soured separated milk) reached puberty earlier and had a greater ovulation rate and greater embryo survival and litter size at 26 to 29 days of gestation than gilts fed a diet in which the supplemental animal protein was replaced with protein of plant origin. Most of the advantage of the animal protein diet was eliminated when the all-plant diet was supplemented with …
Effect Of Plane Of Nutrition, Sex And Bodyweight On The Chemical Composition Of Yorkshire Pigs, G. M. Babatunde, W. G. Pond, L. Dale Van Vleck, G. H. Kroening, J. T. Reid
Effect Of Plane Of Nutrition, Sex And Bodyweight On The Chemical Composition Of Yorkshire Pigs, G. M. Babatunde, W. G. Pond, L. Dale Van Vleck, G. H. Kroening, J. T. Reid
Department of Animal Science: Faculty Publications
An experiment was carried out involving the full- vs. limited-feeding of 9 pairs of gilts and 6 of barrows from a population of closely related Yorkshire pigs from approximately 45 kg. live weight up to each of three predetermined slaughter weight groups (79, 90 and 102 kg.). The objective was to determine the effects of level of feed intake, sex and weight on the chemical composition of the empty body, edible carcass and inedible parts (offal) and the fatty acid composition of the mid-back fat. As the slaughter weight increased, the percentages of empty body, carcass and offal protein and …
Availability Of Niacin In Corn And Milo For Swine, W. G. Luce, E. R. Peo, Jr., D. B. Hudman
Availability Of Niacin In Corn And Milo For Swine, W. G. Luce, E. R. Peo, Jr., D. B. Hudman
Department of Animal Science: Faculty Publications
Niacin has been recognized for several years as a dietary essential for swine. Its presence in feedstuffs is well known, but the biological availability of niacin in certain cereal grains commonly fed to swine has not been clearly established. Research has been reported indicating the niacin of white corn and wheat is largely unavailable to the pig (Kodieek et al., 1956; Kodicek et al., 1959 and Luce et al., 1966). Several workers have also obtained evidence that the niacin of corn is in a bound form and largely unavailable to the rat. (Laguna and Carpenter, 1951; Pearson …
Influence Of A Dietary Supplement Of Lysine Feed At Two Levels Of Protein On Growth, Feed Efficiency And Carcass Characteristics Of Swine, M. H. Jurgens, D. B. Hudman, C. H. Adams, E. R. Peo, Jr.
Influence Of A Dietary Supplement Of Lysine Feed At Two Levels Of Protein On Growth, Feed Efficiency And Carcass Characteristics Of Swine, M. H. Jurgens, D. B. Hudman, C. H. Adams, E. R. Peo, Jr.
Department of Animal Science: Faculty Publications
Mertz et al. (1949) demonstrated that lysine is essential in the nutrition of swine. Since then considerable research has been conducted to determine the level of lysine needed to promote optimum growth and feed conversion in swine. Recent investigations (Crum et al., 1964; Wallace et al., 1964; Jensen et al., 1965) have been designed to measure the physical and chemical changes in the animal body which may accompany observed differences in performance due to varying lysine and protein levels.
Effect Of Artificial Insemination On Frequency Of Undesirable Recessive Genes, L. Dale Van Vleck
Effect Of Artificial Insemination On Frequency Of Undesirable Recessive Genes, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Reduction in the frequency of' undesirable recessive genes is examined for several combinations of initial gene frequencies and number of offspring obtained by random mating of young sires to the population. Only sires not having affected offspring are then returned to heavy use. Such selection can very rapidly reduce the number of affected offspring, if the initial gene frequency is high or if the number of tested offspring is 200-500 for lower gene frequencies. For some combinations, frequency of affected offspring in the population is higher after two or three generations of selection than in the first generation of selection. …
Voluntary Intake Of Forage By Holstein Cows As Influenced By Lactation, Gestation, Body Weight, And Frequency Of Feeding, W. L. Johnston, G. W. Trimberger, M. J. Wright, L. Dale Van Vleck, C. R. Henderson
Voluntary Intake Of Forage By Holstein Cows As Influenced By Lactation, Gestation, Body Weight, And Frequency Of Feeding, W. L. Johnston, G. W. Trimberger, M. J. Wright, L. Dale Van Vleck, C. R. Henderson
Department of Animal Science: Faculty Publications
Relationships involving forage appetite and frequency of feeding forage were studied with high-producing Holstein cows, including 60 complete cow lactations and 49 records of the dry period. Significant correlation (r= .59) was obtained between forage dry matter intake and 4% FCM yield in the lactation period. Patterns of forage DM intake were affected strongly by different stages of the lactation and dry periods. Infrequent periods of hot summer weather decreased intake and milk yield by about 10%. Individual cow differences, however, were the most important source of variation in forage DM intake. Age, body weight changes, body condition, and stage …
Relationships Among Some Physical And Chemical Parameters Of Full- Versus Limited-Fed Yorkshire Pigs Slaughtered At Different Live Weights, G. M. Babatunde, W. G. Pond, L. Dale Van Vleck, G. H. Kroening, J. T. Reid, J. R. Stouffer, G. H. Wellington
Relationships Among Some Physical And Chemical Parameters Of Full- Versus Limited-Fed Yorkshire Pigs Slaughtered At Different Live Weights, G. M. Babatunde, W. G. Pond, L. Dale Van Vleck, G. H. Kroening, J. T. Reid, J. R. Stouffer, G. H. Wellington
Department of Animal Science: Faculty Publications
An experiment was designed using 30 Yorkshire pigs to study the influence of slaughter weight and feed restriction on carcass cut-out data and to relate these physical measurements to the chemically-determined proximate components. As slaughter weight increased from 79 to 102 kg., the percent of all lean cuts decreased significantly, while that of fat cuts and back-fat thickness increased significantly. Absolute amounts of both fat and lean cuts increased with slaughter weight. Feed restriction significantly increased most of the lean parameters studied and reduced the fat measurements. It increased percent of head and reduced the percent of offal (gastrointestinal tract …
Paternal Half-Sib Correlations Between Pairs In The Same And Different Herds, L. Dale Van Vleck
Paternal Half-Sib Correlations Between Pairs In The Same And Different Herds, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Correlations were computed between first lactation milk records expressed as deviations from herd-mate averages of pairs of Holstein paternal half-sibs in the same and in different herds. These were compared to the comparable daughter-dam regressions. After correcting the daughter-dam regression for environmental correlation and change in variance from the dam to the daughter generation, both the daughter- dam and paternal half-sib estimates of heritability were about .34, which suggests that maternal genetic variance is. unimportant. This estimate is, however, higher than the .25 found from the paternal half-sib estimate from an analysis for variance components.
The comparison of the half-sib …
Genetic Covariances Among Relatives For Dairy Lactation Records, L. Dale Van Vleck, G. E. Bradford
Genetic Covariances Among Relatives For Dairy Lactation Records, L. Dale Van Vleck, G. E. Bradford
Department of Animal Science: Faculty Publications
Trios of first lactation records of a cow, her dam, and her granddam were analyzed in an attempt to distinguish between additive by additive genetic effects and maternal genetic effects as possible explanations of much higher heritability estimates from daughter-dam regression than from paternal half-sib correlations. The results based on first lactation records expressed as deviations from herdmate averages suggest that additive by additive effects, and probably environmental correlation contribute little or nothing to covariance between daughter and dam records. Genetic maternal effects may account for about 20% and direct additive genetic effects for 23% of within-herd variance for first …
Changes In Milk Production In Relation To Changes In Feeding And Management Practices In Dairy Herd Improvement Association Herds, J. B. Stone, J. D. Burke, H. R. Ainslie, L. Dale Van Vleck
Changes In Milk Production In Relation To Changes In Feeding And Management Practices In Dairy Herd Improvement Association Herds, J. B. Stone, J. D. Burke, H. R. Ainslie, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
All Holstein herds of over 20 cows which had automated data processed dairy herd improvement association (DHIA) records from Cornell laboratory for two consecutive years from 1960 to 1964 were used to determine production, feeding, and management changes. The average number of herds for the four 2-yr comparisons was 2,688, 60% in New York and the remainder in neighboring states. Results in the two locations agreed. The yearly changes and standard deviations of changes per cow for the New York herds were milk production, + 157 ± 400 kg; grain feeding, + 88 ± 241 kg; succulent forage, + 0.13 …
Change In Variance Components Associated With Milk Records With Time And Increase In Mean Production, L. Dale Van Vleck
Change In Variance Components Associated With Milk Records With Time And Increase In Mean Production, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
First-lactation milk records of artificially sired Holstein cows in New York were analyzed by a sire-by-herd variance component analysis separately for each year from 1954 to 1962. The two variables analyzed were 305-day, 2 ×, mature equivalent records and the mature equivalent records expressed as deviations from the average of their herd-mates. The total variance steadily increased with change in time. Most of the increase (r = .97) was accounted for by increase in mean production. The relative increase in the sire component of variance was slightly faster than the increase in residual variance. Thus, heritability estimated from the paternal …
Correlations Among Records Of Unrelated Cows In The Same Herd And The Same And Different Year-Seasons, L. Dale Van Vleck
Correlations Among Records Of Unrelated Cows In The Same Herd And The Same And Different Year-Seasons, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Correlations were computed between pairs of first-lactation milk records of unrelated Holstein cows in New York, where the records were made in the same herd and same year-season of freshening, and in the same herd but different year-seasons of freshening. Records were expressed as deviations from herd-mate averages. The average correlation between pairs in the same herd-year-season was .01. The average correlation when the pair of records was made one season apart was .08, and two seasons apart was .06. The pattern of correlations between a pair of records made more than 3 or 2 yr apart appears to be …
Heritability Estimates Of Milk Production With Different Numbers Of Records Per Sire By Herd Subclass, L. Dale Van Vleck
Heritability Estimates Of Milk Production With Different Numbers Of Records Per Sire By Herd Subclass, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The first-lactation milk records of 20,850 artificially sired Holstein cows and their darns were analyzed by a sire-by-herd, variance components model to determine if unequal numbers of records in the filled subclasses had any effect on the paternal half-sib correlation or the daughter-dam regression. The variance components were estimated with the number per subclass held constant at 1, 2, 3, 4, or 5. The records were also analyzed as deviations from herdmate averages. The analysis of deviations with one observation per subclass gave the highest heritability estimate from daughter-dam regression, .40, and the lowest from paternal half-sib correlation, .23. Analyses …
Environmental Correlations In Sire Evaluation, L. Dale Van Vleck
Environmental Correlations In Sire Evaluation, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Correlations were computed among averages of first lactation deviations from herdmate averages of groups of artificially sired daughters of the same Holstein bulls. The groups were constructed by specifying the time interval between animals in the different groups. Comparison of the actual correlations with the expected correlations suggests that environmental correlations are small or nil among artificially sired halfsibs in New York. The correlations between initial and later groups of 20 or 40 daughter records at different time intervals are so close to the expected correlations that there is no support for the view that accuracy of prediction in sire …
Genetic And Maternal Influence On The First Three Lactations Of Holstein Cows, L. Dale Van Vleck, G. E. Bradford
Genetic And Maternal Influence On The First Three Lactations Of Holstein Cows, L. Dale Van Vleck, G. E. Bradford
Department of Animal Science: Faculty Publications
Milk records of up to the first three lactations of artificially sired Holstein daughters and their dams were used to estimate heritability from both daughter-dam regression and paternal half-sib correlation. The within-herd estimates from records expressed as deviations from herd-mate averages were .37, .30, and .24 from daughter-dam regression for the first three lactations ; and the corresponding estimates from half-sib correlation were .24, .21, and .23. These results suggest a large maternal effect in the first lactation, a small amount in the second, and little in the third lactation. Analysis of the records not as deviations gave the same …
Linearity Of Heritability Of Holstein First-Lactation Milk Production, L. Dale Van Vleck, C. L. Hart
Linearity Of Heritability Of Holstein First-Lactation Milk Production, L. Dale Van Vleck, C. L. Hart
Department of Animal Science: Faculty Publications
The regression of daughter on dam first-lactation milk deviations from herd-mate averages was found to be linear from an analysis of 47,400 Holstein pairs. The linear equation was y=-25.6 + .210 (x -27.6) and the quadratic equation was y=-25.6 + .208 (x -27.6) + .0000222 (x2-44131.4) with correlation coefficients, .18258 and .18268, respectively. These results suggest that selection response can be predicted adequately even with very large selection differentials.
Production Differences Between Registered Cows And Their Nonregistered Herd-Mates, L. Dale Van Vleck, J. D. Burke
Production Differences Between Registered Cows And Their Nonregistered Herd-Mates, L. Dale Van Vleck, J. D. Burke
Department of Animal Science: Faculty Publications
Within-herd contemporary comparisons of the first-lactation production of registered and nonregistered cows in herds enrolled in the New York Dairy Herd Improvement Associations suggest only small genetic differences between registered and nonregistered cows. In general, the registered Holsteins exceeded in production their nonregistered herd-mates, whereas the nonregistered cows had a slight advantage over their registered herd-mates for the Ayrshire, Guernsey, and Jersey breeds.
Artificially sired cows had consistently higher production than their naturally sired herd-mates for all breeds. A definite increase in this advantage was noted for Holsteins in more recent years. No trend was apparent in the comparison of …
Heritability Estimates Of Udder Disease As 5ieasured By Various Tests And Their Relationship To Each Other And To Milk Yield, Age, And Milking Tisies, G. H. Schmidt, L. Dale Van Vleck
Heritability Estimates Of Udder Disease As 5ieasured By Various Tests And Their Relationship To Each Other And To Milk Yield, Age, And Milking Tisies, G. H. Schmidt, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Paternal half-sib heritability estimates oi' milk yield, number of quarters infected with mastitis organisms, and number <>f quarters showing abnormal mill; were obtained from an analysis of milking and mastitis data of 2,865 Holstein cows. The within-herd heritability estimate for daily milk yield was 0.353 and that for the number of quarters infected with Streptococcus agalactiae 0.196. The heritability estimates for the number of quarters infected with organisms other than Streptococcus agalactiae, number of quarters infected, and number of quarters showing abnormal milk were all below 0.1.
Within-herd correlation coefficients were calculated among daily milk yield, milking data, age, …
Luteotropic Properties Of Luteinizing Hormone And Nature Of Oxytocin Induced Luteal Inhibition In Cattle, Lloyd Donaldson, William Hansel, L. Dale Van Vleck
Luteotropic Properties Of Luteinizing Hormone And Nature Of Oxytocin Induced Luteal Inhibition In Cattle, Lloyd Donaldson, William Hansel, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Fifty-three Holstein heifers were used to study the effects of oxytocin administered alone and in combination with various gonadotropins on the weights and progesterone contents of corpora lutea. Pituitary gonadotropin levels were compared in untreated and oxytocin-treated heifers at three stages of the estrous cycle.
Oxytoein injections on Days 2 through 6 significantly reduced the weights and total progesterone contents but not the progesterone concentrations of glands removed on Day 7. The concurrent administration of either purified bovine luteinizing hormone (LH) or human chorionic gonadotropin (HCG) significantly increased these parameters from the oxytocin treatment levels to normal or supra-normal values. …
Litter Size And Proportion Of Females In The Offspring Of Multiparous Rats With Varying Uterine Metabolic Levels, A. B. Schutz
Litter Size And Proportion Of Females In The Offspring Of Multiparous Rats With Varying Uterine Metabolic Levels, A. B. Schutz
Department of Animal Science: Faculty Publications
The rate of TTC reduction by the uterine tissue of rats was determined at specific stages of the oestrous cycle, and in successive cycles at the same stage. Individual females showed a characteristic level of reaction to TTC. Mothers whose uteri had a high reaction rate with TTC produced litters with a higher percentage of female pups than did mothers with a low level of reaction. Previous studies have shown that TTC reduction rate represents a metabolic activity of uterine tissue that is induced by oestrogens.
Statistics In The Design And Analysis Of Physiology Experiments, L. Dale Van Vleck, C. R. Henderson
Statistics In The Design And Analysis Of Physiology Experiments, L. Dale Van Vleck, C. R. Henderson
Department of Animal Science: Faculty Publications
Statistics should be considered as a tool by the animal experimenter in much the same way that a chemical analysis or a radiation counter is used as a tool. Too often statistics is considered as something magical which can restore order out of chaos and perhaps absolve the experimenter from mistakes in logic and procedure. It is true of course that the statistician through his knowledge of statistical procedures can sometimes help salvage some results from an otherwise hopelessly muddled experiment. One point must be made clear at the outset—the statistician is not a tool of the experimenter although statistics …
Effect Of Ferrous Fumarate In The Lactation Diet On Sow Milk Iron, Pig Hemoglobin And Weight Gain, T. L. Veum, J. T. Gallo, L. Dale Van Vleck, J. K. Loosli
Effect Of Ferrous Fumarate In The Lactation Diet On Sow Milk Iron, Pig Hemoglobin And Weight Gain, T. L. Veum, J. T. Gallo, L. Dale Van Vleck, J. K. Loosli
Department of Animal Science: Faculty Publications
Two experiments involving 22 litters were conducted to study the effects of adding ferrous fumarate to the lactation diet on iron level of sow’s milk and on weight gains and hemoglobin levels of suckling pigs. Ferrous fumarate was not effective in increasing iron content of milk, when added to the lactation diet at a level of 1984 mg. of iron per kg. The increase in hemoglobin level observed at 24 days in Experiment I and at 21 days in Experiment II, in litters nursing sows fed ferrous fumarate, was due to the pigs’ obtaining a source of iron from the …
Comparison Of Heritability Estimates From Daughter-Dam Regression And Paternal Half-Sib Correlation, L. Dale Van Vleck, G. E. Bradford
Comparison Of Heritability Estimates From Daughter-Dam Regression And Paternal Half-Sib Correlation, L. Dale Van Vleck, G. E. Bradford
Department of Animal Science: Faculty Publications
Analysis of 60,000 pairs of daughter and dam first-lactation records expressed as deviations from herd-mate averages for five breeds yielded markedly different heritability estimates from daughter-dam regression than from paternal half-sib correlation. These results suggest that 18% of the within-herd variation is due to genetic maternal effects. The same records analyzed as mature equivalent records and not as deviations but by a sire by herd model did not show this difference. Confounding between year and sire effects probably biased the intraclass correlation estimates upward in the latter analysis, since year effects were not included in the statistical model.
Heritability Estimates When Dams And Daughters Are In The Same And Different Herds, L. Dale Van Vleck, C. L. Hart
Heritability Estimates When Dams And Daughters Are In The Same And Different Herds, L. Dale Van Vleck, C. L. Hart
Department of Animal Science: Faculty Publications
The regression of daughter on dam deviations of Holstein first-lactation milk production from herd-mate averages was computed for 38,440 pairs of records made in the same herd and for 10,256 pairs of records where the daughter was in one herd and the dam in another. The corresponding heritability estimates were .42 and .40, respectively, which suggest an environmental covariance of .01 between records of daughters and dams in the same herd. Other analyses were conducted for dams with two daughters with records where 1) both had records in the same herd as the dam, 2) only one had a record …
Differences Among Appraisers In The New York Type Appraisal Program, L. Dale Van Vleck, R. Albrectsen
Differences Among Appraisers In The New York Type Appraisal Program, L. Dale Van Vleck, R. Albrectsen
Department of Animal Science: Faculty Publications
The purpose of the New York type appraisal program is to attempt to rate type traits objectively. Approximately 34 traits are included, of which 25 are rated by the appraiser and 9 by the herd manager. This paper reports differences among 18 appraisers, including S professional judges, 7 New York Artificial Breeders' Cooperative fieldmen, and 3 other sire selection personnel all of whom rated 38 cows in a single herd. There were statistically significant differences (P ≤ .05) among appraisers for all traits. Average scores of the professionals were different from those of the fieldmen for all except six traits. …
Heritability In Relation To Selection Differential In Cattle, G. E. Bradford, L. Dale Van Vleck
Heritability In Relation To Selection Differential In Cattle, G. E. Bradford, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The concept of heritability as generally used, involves the assumption that additive genetic variance is a constant proportion of total variance over the entire range of phenotypes. If this assumption holds, selection response will be linearly related to selection differential. If not, prediction of selection response will not be possible from a knowledge of the phenotypic selection differential and the average proportion of additive genetic variance. Thus the validity of this assumption has a bearing on the design of efficient selection schemes for many situations. In the field of applied animal breeding, for example, this will affect such important questions …
Effect Of Amino Acid Supplementation Of Rations Containing Meat And Bone Scraps On Rate Of Gain, Feed Conversion And Digestibility Of Certain Ration Components For Growing-Finishing Swine, W. G. Luce, E. R. Peo, Jr., D. B. Hudman
Effect Of Amino Acid Supplementation Of Rations Containing Meat And Bone Scraps On Rate Of Gain, Feed Conversion And Digestibility Of Certain Ration Components For Growing-Finishing Swine, W. G. Luce, E. R. Peo, Jr., D. B. Hudman
Department of Animal Science: Faculty Publications
Previous work at this station (Peo and Hudman, 1962) has shown that meat and bone scraps, when fed at levels from 5 to 10% of the total ration, significantly depress rate of gain of growing-finishing swine. Similar results have been reported by Bloss et al. (1953), Terrill et al. (1954), Meade and Teter (1957), and Becker and Jensen (1961).
Genotype And Variability In Dairy Lactation Records, L. Dale Van Vleck, G. R. Barr
Genotype And Variability In Dairy Lactation Records, L. Dale Van Vleck, G. R. Barr
Department of Animal Science: Faculty Publications
In quantitative genetics, the variation of individuals within genetic groups is commonly attributed to environment. The assumption is then made that the environmental variances are similar from one group to another. Complications arise in the application of selection index theory when this assumption is not made. The results reported here indicate that in a population of dairy records, the environmental variance is not similar from one genetic group to another. Johnson (1945) and Wadell, Van Vleck and Henderson (1960) found similar results with fewer data.
Effects Of Management, Strain And Truck Shipment On Albumen Quality Of Eggs, J.L. Adams, J.L. Skinner
Effects Of Management, Strain And Truck Shipment On Albumen Quality Of Eggs, J.L. Adams, J.L. Skinner
Department of Animal Science: Faculty Publications
Very little has been reported on changes in quality of eggs during shipment. Gwin (1952) reported a study involving more than a billion eggs purchased by the Armed Forces of the United States. U.S. Grades were determined by candling and inspection by trained inspectors from the Army Veterinary Corps and the U.S. Department of Agriculture. Quality loss was shown to be related to time in transit, distance or miles in transit and seasonal influences. No data were reported as to the relation of varying physical conditions during transit or position effects within the rail cars. Adams and Milam (1960) studied …