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Department of Animal Science: Faculty Publications

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Environmental Correlations In Sire Evaluation, L. Dale Van Vleck Jul 1965

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 …

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Change In Variance Components Associated With Milk Records With Time And Increase In Mean Production, L. Dale Van Vleck Jul 1965

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 …

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Heritability Estimates Of Milk Production With Different Numbers Of Records Per Sire By Herd Subclass, L. Dale Van Vleck Jul 1965

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 …

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Genetic And Maternal Influence On The First Three Lactations Of Holstein Cows, L. Dale Van Vleck, G. E. Bradford Jun 1965

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 …

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Linearity Of Heritability Of Holstein First-Lactation Milk Production, L. Dale Van Vleck, C. L. Hart May 1965

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.

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Production Differences Between Registered Cows And Their Nonregistered Herd-Mates, L. Dale Van Vleck, J. D. Burke Feb 1965

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 …

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Litter Size And Proportion Of Females In The Offspring Of Multiparous Rats With Varying Uterine Metabolic Levels, A. B. Schutz Jan 1965

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.

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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 Jan 1965

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 …

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Statistics In The Design And Analysis Of Physiology Experiments, L. Dale Van Vleck, C. R. Henderson Jan 1965

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 …

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Comparison Of Heritability Estimates From Daughter-Dam Regression And Paternal Half-Sib Correlation, L. Dale Van Vleck, G. E. Bradford Jan 1965

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.

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Differences Among Appraisers In The New York Type Appraisal Program, L. Dale Van Vleck, R. Albrectsen Jan 1965

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. …

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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 Jan 1965

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, …

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Luteotropic Properties Of Luteinizing Hormone And Nature Of Oxytocin Induced Luteal Inhibition In Cattle, Lloyd Donaldson, William Hansel, L. Dale Van Vleck Jan 1965

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. …

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Heritability Estimates When Dams And Daughters Are In The Same And Different Herds, L. Dale Van Vleck, C. L. Hart Jan 1965

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 …

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Heritability In Relation To Selection Differential In Cattle, G. E. Bradford, L. Dale Van Vleck May 1964

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 …

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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 Jan 1964

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).

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Genotype And Variability In Dairy Lactation Records, L. Dale Van Vleck, G. R. Barr Nov 1963

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.

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Effects Of Management, Strain And Truck Shipment On Albumen Quality Of Eggs, J.L. Adams, J.L. Skinner Jan 1963

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 …

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Evaluation Of Sires Available Through Planned Mating, L. Dale Van Vleck, C. R. Henderson, H. W. Carter Jan 1962

Evaluation Of Sires Available Through Planned Mating, L. Dale Van Vleck, C. R. Henderson, H. W. Carter

Department of Animal Science: Faculty Publications

There is some concern that methods of sire evaluation which utilize contemporary stablemate averages can be biased by differential genetic merit of the mates of these sires. A little reflection, however, indicates that even if the cows to which some sires are mated are more highly selected than the mates of other sires, this differential merit will not affect seriously the ranking of sires according to the evaluation of their progeny. Until the present, data have not been readily available with which to study the seriousness of this problem. The present study does not deal with the question generally, but …

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Sire Evaluation From Five-Month Daughter Records, L. Dale Van Vleck Jan 1962

Sire Evaluation From Five-Month Daughter Records, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

The chief advantages of sire evaluation based on five-month daughter records are: 1. Genetic progress is inversely proportional to the turnover rate in testing bulls so that if this interval is shortened by 10%, the rate of genetic progress will be increased by 11%. The turnover period can be shortened with the use of 5-month records from about 50 months to 45 months—a decrease of 10% in time. 2. Genetic progress is also related to how many top bulls are saved and how many poor ones are culled out of all those sampled. In other words, the more bulls tested …

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Effect Of Levels Of Meat And Bone Scraps On Growth Rate And Feed Efficiency Of Growing-Finishing Swine, E. R. Peo, Jr., D. B. Hudman Jan 1962

Effect Of Levels Of Meat And Bone Scraps On Growth Rate And Feed Efficiency Of Growing-Finishing Swine, E. R. Peo, Jr., D. B. Hudman

Department of Animal Science: Faculty Publications

Many investigations have shown that soybean meal when properly supplemented can replace meat and bone scraps as a major source of protein in swine rations (Lepley et al., 1950; Terrill et al., 1954; Rohlf, 1954; Meade and Hanson, 1957; Meade et al., 1958; Becker et al., 1960). The importance of this finding is emphasized by the work of Bloss et al. (1953), Terrill et al. (1954), Meade and Teter (1957) and Becker and Jensen (1961) who reported a significant depression in growth rate and feed efficiency of swine fed rations containing relatively high levels …

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Parameters For Milk Yield And For Percents Of Ash, Dry Matter, Fat And Protein In Sows, W. G. Pond, L. Dale Van Vleck, D. A. Hartman Jan 1962

Parameters For Milk Yield And For Percents Of Ash, Dry Matter, Fat And Protein In Sows, W. G. Pond, L. Dale Van Vleck, D. A. Hartman

Department of Animal Science: Faculty Publications

Milk was collected separately by machine from four to six glands on nine Yorkshire and Berkshire sows 2 or 3 days after farrowing and at weekly intervals throughout 6 weeks of lactation. Milk yield was measured following intramuscular injection of oxytocin, and the percent of ash, dry matter, fat and protein in the milk from each gland was determined. The average milk yield per gland, following a 1-hour period during which the pigs had been removed from the sow reached a peak of 74.6 gm. 3 weeks after farrowing. The ash content was 0.79% 2 or 3 days after farrowing, …

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Components Of Variance Associated With Milk And Fat Records Of Artificially Sired Holstein Daughters, L. Dale Van Vleck, L. H. Wadell, C. R. Henderson Jan 1961

Components Of Variance Associated With Milk And Fat Records Of Artificially Sired Holstein Daughters, L. Dale Van Vleck, L. H. Wadell, C. R. Henderson

Department of Animal Science: Faculty Publications

Components of variance are estimated for the three-way classification analysis of variance of DHIA reported first and second milk and fat records of artificially sired Holstein cows and of Owner-Sampler reported milk and fat records of artificially sired Holstein cows. The total variance of milk and fat records is partitioned into the following components with the approximate percent of total variance: sire, 6%; year-season, 2%; herd, 30%; sire by year-season, 0%; sire by herd, 1–2%; herd by year-season, 6–8%; sire by herd by year-season, 1–7%; and residual, 50%.

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Carcass Characteristics Of Swine As Influenced By Levels Of Protein Fed In Pasture And In Dry Lot, D. B. Hudman, E. R. Peo, Jr. Jan 1960

Carcass Characteristics Of Swine As Influenced By Levels Of Protein Fed In Pasture And In Dry Lot, D. B. Hudman, E. R. Peo, Jr.

Department of Animal Science: Faculty Publications

Several experiments have been conducted to compare the performance of growing-finishing swine fed on pasture and in dry lot. Most of the early experimental research was conducted with rations that were lacking in vitamin and antibiotic supplementation. In these experiments the pigs fed on pasture tended to gain faster and more efficiently than those fed in dry lot. However, more recent research conducted by Hutchinson et al. (1955, 1956), Conrad and Beeson (1957) and Barnhart, Overfield and Lowry (1959) indicates that with supplemental vitamins and antibiotics, pigs fed in dry lot gained slightly faster than pigs fed on pasture.

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Ratios Of Dried Skim Milk And Dried Whey For Pig Starter Rations, D. M. Danielson, E. R. Peo, Jr., D. B. Hudman Jan 1960

Ratios Of Dried Skim Milk And Dried Whey For Pig Starter Rations, D. M. Danielson, E. R. Peo, Jr., D. B. Hudman

Department of Animal Science: Faculty Publications

Lactose and sucrose were reported by Hudman (1956) to be preferred carbohydrates for pig starter rations. Lactose gave the best growth response when fed with soybean oil meal; sucrose with milk protein. From the analysis listed by Morrison (1956), both dried skim milk and dried whey must be considered as a source of lactose since, on an average, these products contain 51.1 and 70.1% lactose, respectively. In addition, both contain a high quality protein.

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The Number Of Daughter-Dam Pairs Needed For Estimating Heritability, L. Dale Van Vleck, S. R. Searle, C. R. Henderson Jan 1960

The Number Of Daughter-Dam Pairs Needed For Estimating Heritability, L. Dale Van Vleck, S. R. Searle, C. R. Henderson

Department of Animal Science: Faculty Publications

The number of observations required to obtain reliable estimates of heritability has been discussed recently for the method which utilizes the intra-class correlation coefficient. Wearden (1959) has made use of the power function to determine the number of progeny per sire needed to estimate heritability. Tallis (1959), utilizing the formula for the variance of the intra-class correlation coefficient as given by Fisher (1952), has discussed the minimum number of offspring necessary for estimating heritability with a given accuracy.

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Supplementation Of Pig Starters With Thyroprotein, E. R. Peo, Jr., D. B. Hudman Jan 1960

Supplementation Of Pig Starters With Thyroprotein, E. R. Peo, Jr., D. B. Hudman

Department of Animal Science: Faculty Publications

It has been reported that both gains and feed efficiency are improved when pigs are fed thyroprotein during the growth period from weaning to market weight (Reineke et al., 1948; Beeson et al., 1949; Perry et al., 1950; Perry et al., 1951). Contrary results have been reported by Braude (1947), Muhrer et al. (1947) and Vander Noot et al. (1948). No similar research has been reported with baby pigs during

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Grain Sorghum For Growing-Finishing Swine, E. R. Peo, Jr., D. B. Hudman Jan 1958

Grain Sorghum For Growing-Finishing Swine, E. R. Peo, Jr., D. B. Hudman

Department of Animal Science: Faculty Publications

Considerable research has been conducted on the feeding value of grain sorghums for swine. Baker and Reinmiller (1939) observed that for the production of gains, grain sorghums were equal to or better than corn but considerable more feed was required to produce a pound of gain with the sorghums. Loeffel (1957) summarized several Nebraska swine experiments and observed that grain sorghum and corn produced approximately the same average daily gain, but, in general, 10 to 20~o more feed was required per pound of gain with the grain sorghum. Similar results have been reported by Aubel (1950, 1954, 1955, 1956) and …

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Protein And Fat Requirements Of Baby Pigs, E. R. Peo, Jr., G. C. Ashton, V. C. Speer, D. V. Catron Jan 1957

Protein And Fat Requirements Of Baby Pigs, E. R. Peo, Jr., G. C. Ashton, V. C. Speer, D. V. Catron

Department of Animal Science: Faculty Publications

Present day research in swine nutrition with its early weaning programs and its use of the baby pig in biological assays has necessitated the determination of the nutritional requirements of the baby pig. The requirements for two of these nutrients (protein and fat) have not been clearly established. Early studies on the protein and fat requirements of baby pigs were conducted with liquid synthetic milk diets, which were formulated generally on the basis of the composition of sow milk.

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Recent Lamb Feeding Investigations At The University Of Nebraska, H. J. Gramlich Oct 1917

Recent Lamb Feeding Investigations At The University Of Nebraska, H. J. Gramlich

Department of Animal Science: Faculty Publications

During the past several years considerable experimental work has been performed at the University of Nebraska in fattening western lambs. The attractiveness of fattening lambs at prices existing during a series of recent years has caused a material increase in the interest in this work, and we have felt justified in experimenting rather extensively to ascertain the most satisfactory combination of feeds to use under our Nebraska conditions.
The objects in view have been chiefly to ascertain the most satisfactory rations where corn and alfalfa hay constituted the basal feeds. We have used these two feeds extensively because of the …

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