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Full-Text Articles in Agriculture

Motion And Time Studies Of Milking Parlors And Routines, R. D. Appleman, C. F. Micke Mar 1973

Motion And Time Studies Of Milking Parlors And Routines, R. D. Appleman, C. F. Micke

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

This study defines and describes the parameters of milking in both the elevated side-opening and herringbone style milking parlor. Included in this "motion and time" study are measurements of differences in milking routines or techniques, as well as the probable contribution of certain mechanical aids, including both crowd gates and group-washing systems. Milker (men) differences are also identified. Detailed measurements of time requirements for specific milking activities or chores are expensive to obtain. Very limited data are found in the scientific literature. This bulletin is published to supply resource data which may be used in planning milking parlors or as …


Calf Diarrhea (Scours): Reproduced With A Virus From A Field Outbreak, C. A. Mebus, N. R. Underdahl, M. B. Rhodes, M. J. Twiehaus Mar 1969

Calf Diarrhea (Scours): Reproduced With A Virus From A Field Outbreak, C. A. Mebus, N. R. Underdahl, M. B. Rhodes, M. J. Twiehaus

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Neonatal calf diarrhea typical of that seen in field cases was produced in colostrum-deprived calves by inoculating either feces or bacteria-free filtrates via the duodenum, orally, or by a spray (aerosol). Three calves, kept free of E. coli, developed severe diarrhea following inoculation with a bacteria-free filtrate. Intense fluorescence in the epithelium of sections of small intestine from two experimental calves was observed following staining with ftuorescein-labeled gamma globulin produced with viral antigen prepared from the feces of two experimental diarrhetic E. coli-free calves. Fluorescing cells were also present in the feces of experimental and field cases of neonatal …


Relationship Between Measures Of Semen Quality And Fertility In Bulls Mated Under Natural Conditions, J. N. Wiltbank, W. W. Rowden, J. E. Ingalls Dec 1965

Relationship Between Measures Of Semen Quality And Fertility In Bulls Mated Under Natural Conditions, J. N. Wiltbank, W. W. Rowden, J. E. Ingalls

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

An evaluation of the relationship between several measures of semen quality and fertility of bulls mated under natural conditions has been conducted over a three-year period. Semen was collected three different times with an electro-ejaculator from bulls used in the fertility tests. Collections were made at weekly intervals. Fertility was evaluated by mating bulls to heifers starting about three days after the last collection. Semen quality refers to the percent abnormals and the percent motility evaluated at the time of collection. Fertility was measured by the proportion of heifers that settled at natural service. Several multiple regression equations were calculated. …


A Histological Study Of The Postnatal Development Of The Bovine Testis, R. G. Fossland, A. B. Schultze May 1961

A Histological Study Of The Postnatal Development Of The Bovine Testis, R. G. Fossland, A. B. Schultze

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A limited number of detailed studies on the development of the bovine testis from birth to sexual maturity have been reported. Further study of bovine testis development appears desirable to furnish additional observations and to note variations that may occur during the developmental process. Information on the process of spermatogenesis should furnish a basis for experimental work designed to promote increased spermatogenic activity in the postpubertal testis as well as for work directed toward promoting complete spermatogenesis at an earlier than usual age. This report is a study of the histological picture of the testes from 56 bulls varying from …


Relation Of Heart Girth To Weight In Holsteins And Jerseys, H. P. Davis, W. W. Swett, W. R. Harvey Jan 1961

Relation Of Heart Girth To Weight In Holsteins And Jerseys, H. P. Davis, W. W. Swett, W. R. Harvey

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Body weight is the one measurement most extensively used to evaluate growth, condition, and value for beef, and as a basis for calculating feed requirements for cattle. Weight can be determined readily by scales but unfortunately scales of a capacity adequate for weighing cattle are not always available. Thus there is a real need for a basis of estimating weight from some body measurement that can be obtained easily and at a minimum of cost and time. It is the aim of this study to utilize additional data now available to increase further the accuracy and reliability of estimating weight …


Growth Measurements Of Holstein, Ayrshire, Guernsey And Jersey Males, H. P. Davis, I. L. Hathaway Jul 1959

Growth Measurements Of Holstein, Ayrshire, Guernsey And Jersey Males, H. P. Davis, I. L. Hathaway

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

This study was based on monthly observations of all Holstein, Ayrshire, Guernsey and Jersey males born in the University of Nebraska dairy herd between 1922 and 1942. There were varying numbers of animals for the different months of age for the several breeds. Measurements of weight, slope of the rump, thickness of skin, and 13 linear measurements were taken monthly, from birth to disposal of the animals. The linear measurements were of heights at withers, hooks and rump; of lengths-diagonal (shoulder point to pinbone), body and rump; of widths at chest, hooks and pinbones; of depths at chest and barrel; …


Forty Years Of Dairy Cattle Breeding At The North Platte Experiment Station, Mogens Plum, Myron G.A. Rumery May 1956

Forty Years Of Dairy Cattle Breeding At The North Platte Experiment Station, Mogens Plum, Myron G.A. Rumery

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

In 1913 the Nebraska Legislature appropriated $17,500 to establish a Dairy Department at the North Platte Experiment Station. The department's herd was to be used in demonstrating management and breeding practices and as a source of breeding stock. Since the North Platte herd was started, research in the field of animal breeding has developed new concepts in many phases of dairy cattle breeding and selection. The purpose of the present study is to analyze the progress made under a system of dairy cattle breeding and selection carried out according to the principles that dominated 40 years ago. The results of …


Comparative Measurements Of Holstein, Ayrshire, Guernsey, And Jersey Females From Birth To Seven Years, H. P. Davis, I. L. Hathaway Mar 1956

Comparative Measurements Of Holstein, Ayrshire, Guernsey, And Jersey Females From Birth To Seven Years, H. P. Davis, I. L. Hathaway

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Body measurements are important for a proper understanding of how growth takes place in animals. Unfortunately, few growth data other than for weight have been published concerning dairy cattle. This is a report of measurements of females in the University of Nebraska dairy herd made as part of a long-time growth study. During the period 1922 to 1942 each animal born into the herd was weighed and measured at regular intervals. Presented here are the data for weight, height, length, width, depth, girth and hide thickness for females of the Holstein, Ayrshire, Guernsey, and Jersey breeds. The average body measurements …


Growth Measurements Of Holstein Females From Birth To Seven Years, H. P. Davis, I. L. Hathaway Nov 1955

Growth Measurements Of Holstein Females From Birth To Seven Years, H. P. Davis, I. L. Hathaway

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Measurements of growth, to be meaningful, must be taken of various parts of the body, at regular intervals, under standardized environmental conditions, from birth through the growth span of the animal. From these measurements skeletal growth standards may be prepared for the several ages. Such standards can be used to measure growth at any age period. They will serve the research worker as a guide for experimental procedure and will provide the livestock raiser a basis with which his animals may be compared. Present standards of growth for dairy cattle are based mostly upon live weight, although considerable data are …


The Influence Of Length Of Storage Of Bovine Semen On Conception Rate Under Field Conditions, A. B. Schultze, H. P. Davis, C. T. Blunn, M. M. Oloufa May 1948

The Influence Of Length Of Storage Of Bovine Semen On Conception Rate Under Field Conditions, A. B. Schultze, H. P. Davis, C. T. Blunn, M. M. Oloufa

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

It is the purpose of this study to determine whether under conditions of routine handling in artificial breeding associations there is a decline in semen fertility from day to day and also to determine the magnitude of this decline. Tabulation of such data will not only be of value in determining the effect of frequent semen collection on the over-all artificial breeding results but will also serve as a basis of comparison in investigational work directed toward increasing the efficiency of artificial breeding.


Breeding Efficiency In Dairy Cattle From Artificial Insemination At Various Intervals Before And After Ovulation, George W. Trimberger Jan 1948

Breeding Efficiency In Dairy Cattle From Artificial Insemination At Various Intervals Before And After Ovulation, George W. Trimberger

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The length of estrus and the time of ovulation were determined for 46 heifers and 86 cows of the Ayrshire, Guernsey, Jersey, and Holstein breeds by testing for end of estrus and ovulation at 2-hour intervals. Services were given by artificial insemination at various intervals before and after ovulation to determine the influence of this factor on the rate of conception. No significant breed or seasonal differences were found for length of estrus and ovulation time after end of estrus among the four dairy breeds represented in the experiment.


Distillers' By-Products And Soybean Meal In Dry Calf Starters For Calves On Limited Quantities Of Milk, H. P. Davis, G. W. Trimberger Mar 1946

Distillers' By-Products And Soybean Meal In Dry Calf Starters For Calves On Limited Quantities Of Milk, H. P. Davis, G. W. Trimberger

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Whole milk is recognized to be very satisfactory as the principal source of nutrients for young growing calves. But the price of milk and its importance as food for human beings has tended to introduce the use of substitutes. Skim milk has been demonstrated to be a satisfactory substitute when fed with grain after the first few weeks of feeding; but since skim milk, too, has become of increased usefulness for human nutrition, this experiment, one of a series, was designed to determine whether or not combinations of various grains, when fortified with vitamins, could be substituted for the solids …


Carotene Content Of Native Nebraska Grasses, I. L. Hathaway, H. P. Davis, F. D. Keim Oct 1945

Carotene Content Of Native Nebraska Grasses, I. L. Hathaway, H. P. Davis, F. D. Keim

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The carotene content of twenty-four grasses native to Nebraska were determined at approximately monthly intervals from June to November. While the carotene concentration of most of the grasses was moderately high during the growing season, it declined to a rather low point by late November. With the exception of Switchgrass, Hairy Grama, Little Bluestem and Prairie Dropseed, all of the grasses contained enough carotene to supply the needs of range cattle until late November. However, only eighteen of the grasses still contained enough carotene by the latter part of September to furnish the carotene required by dairy cows. Even as …


Protein Supplements In Dry Calf Starters For Calves On Limited Quantities Of Milk, George W. Trimberger, Herbert Perry Davis Aug 1944

Protein Supplements In Dry Calf Starters For Calves On Limited Quantities Of Milk, George W. Trimberger, Herbert Perry Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

This experiment was undertaken to determine the usefulness of various high protein concentrates of animal and plant sources in comparison with dried skim milk in calf starters during the early stages of calf growth.


The Use Of Dried Whey And Blood Meal In The Raising Of Calves On Limited Amounts Of Milk, I. L. Hathaway, G. W. Trimberger, H. P. Davis Oct 1943

The Use Of Dried Whey And Blood Meal In The Raising Of Calves On Limited Amounts Of Milk, I. L. Hathaway, G. W. Trimberger, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The use of substitutes for milk in the raising of calves is always of interest to the progressive dairyman, since there are a number of circumstances in which it is advantageous to reduce the milk feeding period. Producers of market milk often desire to raise their calves on as little milk as possible in order to have more milk available for market. When the demand for milk is good, dairymen who usually market cream only may prefer to sell milk and raise their calves on starters or other milk substitutes. Dairy farmers may wish to use the skim milk generally …


Conception Rate In Dairy Cattle By Artificial Insemination At Various Stages Of Estrus, George W. Trimberger, H. P. Davis Apr 1943

Conception Rate In Dairy Cattle By Artificial Insemination At Various Stages Of Estrus, George W. Trimberger, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A breeding experiment with 295 dairy cows and heifers of the Jersey, Guernsey, Ayrshire, and Holstein breeds was conducted in the University of Nebraska dairy herd. The females were given artificial services at various stages of estrus to determine the effect of time of service upon conception. The results obtained indicate the potential benefits in higher percentage of conception in females bred during the middle of estrus, toward the end of estrus, and those bred in full heat and rebred in 24 hours. The latter is usually not very practical, especially in artificial breeding rings, but there are occasions when …


Influence Of Age Of Dairy Cattle And Season Of The Year On The Sex Ratio Of Calves And Services Required For Conception, R. F. Morgan, H. P. Davis Aug 1938

Influence Of Age Of Dairy Cattle And Season Of The Year On The Sex Ratio Of Calves And Services Required For Conception, R. F. Morgan, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The present study was based on records of the dairy herd of the University of Nebraska for the period 1896 to 1934, and covers five breeds, Holsteins, Jerseys, Guernseys, Ayrshires, and milking Shorthorns. In all, 2,090 cows have been included. The purpose was to determine the influence of the age of the bull, the age of the cow, and the season of the year upon the number of services required for conception, and to determine also the influence of these factors upon the sex ratio of calves born, number of twins born, and the percentage of abortion.


The Vitamin A Content Of Soybean Silage And Of A.I.V., Molasses, And Common Corn Silages, And The Effect Of Feeding These Materials Upon The Vitamin A Content Of Milk, I. L. Hathaway, H. P. Davis, J. C. Brauer Jun 1938

The Vitamin A Content Of Soybean Silage And Of A.I.V., Molasses, And Common Corn Silages, And The Effect Of Feeding These Materials Upon The Vitamin A Content Of Milk, I. L. Hathaway, H. P. Davis, J. C. Brauer

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A study was made of the vitamin A content of soybean silage, and of A.l.V., molasses, and common corn silage. The silages were fed to groups of cows and the vitamin A content of their milk determined. The vitamin A determinations were made by feeding the silage or the milk to groups of rats whose body stores of this vitamin had been depleted by being fed a vitamin-A-deficient ration. Approximately 780 rats were used in these experiments. There were no apparent ill effects of feeding as much as 3.2 grams of the A.l.V. silage per rat per day for eight …


Relation Of Height At Withers And Chest Girth To Live Weight Of Dairy Cattle Of Different Breeds And Ages, H. P. Davis, R. F. Morgan, Samuel Brody, A. C. Ragsdale Jul 1937

Relation Of Height At Withers And Chest Girth To Live Weight Of Dairy Cattle Of Different Breeds And Ages, H. P. Davis, R. F. Morgan, Samuel Brody, A. C. Ragsdale

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The size of a dairy cow is important from the standpoint of feed consumption and economy of production and also as an indication of the expected size of offspring. The ultimate disposal of dairy cattle is for beef, and the measure of returns is based upon size and condition. A method for the determination of the approximate weights of dairy females, where scales are not available, is needed. Measurements of dairy cattle which show development and skeletal growth by ages in relationship to weight are presented here for four different dairy breeds.


The Effect Of Pregnancy And Parturition On The Weight Of Dairy Cows, R. F. Morgan, H. P. Davis Mar 1936

The Effect Of Pregnancy And Parturition On The Weight Of Dairy Cows, R. F. Morgan, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A study was made of the effect of pregnancy and parturition upon the weight cycle of dairy cows of the Ayrshire, Guernsey, Holstein, and Jersey breeds according to gestation periods from data accumulated from records for the period 1922 to 1934 of the dairy herd of the Dairy Husbandry Department of the University of Nebraska. The weights of the cows were obtained from three consecutive weighings made at the middle of each month and daily weighings beginning at the 265th day of pregnancy and continuing for 30 days after calving. A total of 656 separate gestation periods were tabulated according …


The Vitamin E Content Of Certain Dairy Feeds, I. L. Hathaway, H. P. Davis Aug 1934

The Vitamin E Content Of Certain Dairy Feeds, I. L. Hathaway, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A study was made of the vitamin E content of each of the ingredients of our dairy herd ration, excepting the salt, lime, and bone meal. Female rats which were able to conceive but unable to reproduce when fed a diet deficient in vitamin E were fed the various feeds as a source of vitamin E during a second breeding period. The presence of vitamin E in a feed was thus shown by the ability of the female to cast a litter. The vitamin E content of bran, shorts, linseed oil meal, hominy feed, white corn, yellow corn, cottonseed meal, …


The Vitamin A Content Of Skimmilk, Standardized Milk, And Cream From Different Breeds Of Cows, I. L. Hathaway, H. P. Davis Dec 1933

The Vitamin A Content Of Skimmilk, Standardized Milk, And Cream From Different Breeds Of Cows, I. L. Hathaway, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A study was made of the vitamin A content of skimmilk, of milk standardized by the addition of separated milk, and of cream. Rats whose body stores of vitamin A had been depleted by being fed a vitamin A deficient ration were fed either skimmilk, standardized milk, or cream as a source of vitamin A. Approximately 750 rats were used in nine experiments. From the results of these experiments the following conclusions were drawn: (1) that the vitamin A content of milk is associated largely with the butterfat and that separated milk containing a small quantity of fat contains only …


The Influence Of Number Of Daily Milkings On The Production Of Dairy Cows, R. F. Morgan, H. P. Davis Sep 1931

The Influence Of Number Of Daily Milkings On The Production Of Dairy Cows, R. F. Morgan, H. P. Davis

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

High-producing Holstein, Jersey, Ayrshire, and Guernsey cows of various ages milked three times daily produced from 39.69 to 52.26 per cent more fat and from 44.98 to 65.18 per cent more milk than cows milked twice daily. When high-producing cows of all breeds milked four times daily were compared with cows milked twice daily, the fat production for the several age classes varied from 110.19 to 127.53 per cent and the milk production from 149.08 to 160.31 per cent greater for those milked four times. Milking high-producing cows four times as compared with three times daily showed an increased fat …


The Vitamin A Content Of The Milk Of Holstein, Ayrshire, Jersey, And Guernsey Cows, H. P. Davis, I. L. Hathaway Feb 1931

The Vitamin A Content Of The Milk Of Holstein, Ayrshire, Jersey, And Guernsey Cows, H. P. Davis, I. L. Hathaway

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

A comparative study of the vitamin A content of milk produced by Holstein, Ayrshire, Jersey, and Guernsey cows was made by comparing the growth produced by 560 rats receiving milk from these breeds as their only source of vitamin A. The results showed some slight irregular differences in the gains produced by the milk from the different breeds. When these differences were considered in view of the individual variation of the experimental animals, they appeared negligible. This conclusion was substantiated by a statistical examination of the data. From the results of this study in which the experiments were duplicated, it …


Economic Aspects Of Contagious Abortion In A Dairy Herd, Department Of Animal Husbandry May 1930

Economic Aspects Of Contagious Abortion In A Dairy Herd, Department Of Animal Husbandry

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The object of this study is to present the measurable losses due to abortion in a dairy herd of high-producing ability over a period of approximately one-third of a century. The records available provide a rather complete history of what has taken place.