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Articles 1141 - 1170 of 1242
Full-Text Articles in Animal Sciences
Genetic Value Of Sexed Semen To Produce Dairy Heifers, L. Dale Van Vleck, R. W. Everett
Genetic Value Of Sexed Semen To Produce Dairy Heifers, L. Dale Van Vleck, R. W. Everett
Department of Animal Science: Faculty Publications
Economic value of sexed semen due to increased intensity of selection on cows to produce replacements can be determined from a slight modification of a procedure used to predict net worth of semen of different costs from sires of different transmitting abilities. Table values corresponding to precision of sexing (selection intensity allowed for cows), discount rate, investment period, and conception rate are used in simple equations to determine the economic value of sexed or regular semen. The additional price that can be paid for sexed semen as compared to regular semen also can be determined. For example, sexed semen resulting …
Reproductive Efficiency Of Jerseys, Red Sindhis, And Crossbreds, R. E. Mcdowell, B. F. Hollow, J. K. Camoens, L. Dale Van Vleck
Reproductive Efficiency Of Jerseys, Red Sindhis, And Crossbreds, R. E. Mcdowell, B. F. Hollow, J. K. Camoens, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Ten measures related to breeding efficiency were used for comparisons among pure Jerseys and Red Sindhis and crossbreds with ¾, ½, or ¼ European dairy inheritance (Brown Swiss, Holstein, or Jersey) at two locations. Jerseys and crossbreds were common to both herds with Sindhis only at Jeanerette. Means for age at puberty (first estrus after 12 mo) were 425 ± 4.2, 434 ± 6.9, 459 ± 6.9, 504 ± 14.1, and 717 ± 40.4 days for Jerseys, crosses of ¾, ½, or ¼ and Sindhi. The increase in age of puberty was additive but not entirely. The ¾and ½ tended …
Influence Of Exercise On Performance And Carcass Parameters Of Confinement Reared Swine, G. M. Weiss, E. R. Peo, Jr., R. W. Mandingo, B. D. Moser
Influence Of Exercise On Performance And Carcass Parameters Of Confinement Reared Swine, G. M. Weiss, E. R. Peo, Jr., R. W. Mandingo, B. D. Moser
Department of Animal Science: Faculty Publications
Fifty-six crossbred growing and finishing swine were used to determine the effect of treadmill exercise on several performance and carcass parameters When housed in confinement on 100% slatted floors. The exercised swine were subjected to walking 1.6 km/hr for 1 hr 5 days per week. The mean experimental duration was 71 days. Jugular vein blood samples and gracilus muscle biopsy samples were obtained prior and following completion of exercise. Exercise had no major influence on average daily gain, daily feed intake or gain/feed ratio. Bone breaking strength of the left fourth metatarsal was significantly (P <.01) greater for exercised pigs than non exercised. However, right third and fourth metatarsal and left third metatarsal bone breaking strengths were not influenced by exercise.
Maternal Heterosis In Swine: Reproductive Performance And Dam Productivity, R. K. Johnson, I. T. Omtvedt
Maternal Heterosis In Swine: Reproductive Performance And Dam Productivity, R. K. Johnson, I. T. Omtvedt
Department of Animal Science: Faculty Publications
The objectives of this study were to estimate the heterosis of crossbred gilts for ovulation rate and the maternal heterosis of crossbred gilts for dam productivity. A total of 470 gilts were saved for breeding of which 72 were considered reproductive failures. Estimates of heterosis were made from 193 pregnant gilts slaughtered 30 days postbreeding (106 crossbred and 87 purebred)and 192 litters farrowed (98 three-breed and 94 two-breed cross). The reproductive failure rate for all gilts was 15.3% with there being very little difference~ between purebred and crossbred gilts. Estimates of heterosis for ovulation rate were not significantly different from …
Effects Of Source On Copper Uptake By Swine, G. L. Zoubek, E. R. Peo, Jr., B. D. Moser, T. Stahly, P. J. Cunningham
Effects Of Source On Copper Uptake By Swine, G. L. Zoubek, E. R. Peo, Jr., B. D. Moser, T. Stahly, P. J. Cunningham
Department of Animal Science: Faculty Publications
Four catheterized crossbred (Y x H) barrows were used in a 4 x 4 latin square arrangement of treatments in a completely randomized block design, to determine the effect of source on copper uptake as determined by serum Cu concentration changes over a 7.5-hr sampling period.
Oestrus, Lh, Ovulation And Fertility In Beef Heifers, R. K. Christenson, S. E. Echternkamp, D. B. Laster
Oestrus, Lh, Ovulation And Fertility In Beef Heifers, R. K. Christenson, S. E. Echternkamp, D. B. Laster
Department of Animal Science: Faculty Publications
The pregnancy rate resulting from matings at a single oestrus in beef cattle averages 70% for natural mating (Turman, Laster, Renbarger & Stephens, 1971) and 60% for artificial insemination (Laster, Glimp & Gregory, 1972). The sources and causes of low pregnancy rates have not been defined, but might include variation in time of ovulation relative to deposition of spermatozoa in the female reproductive tract, fertilization failure, ovum transport, abnormal ova and blastocyst development, and implantation failure. The interval from onset of oestrus to ovulation in dairy cattle has been reported to average 29±6hr with a range from 16 to 42 …
Relationship Of Various Measures Of Performance With Ovulation Rate And Number Of Embryos 30 Days After Breeding In Gilts, L. D. Young, I. T. Omtvelt, R. K. Johnson
Relationship Of Various Measures Of Performance With Ovulation Rate And Number Of Embryos 30 Days After Breeding In Gilts, L. D. Young, I. T. Omtvelt, R. K. Johnson
Department of Animal Science: Faculty Publications
This study involved the records of 241 purebred Duroc, Hampshire and Yorkshire gilts and 103 two-breed cross gilts resulting from all possible crosses among the purebreds. In purebred gilts, the number of corpora lutea was correlated (P < .05) with average daily gain (r = 0.15), age at 100 kg(r =-.17), breeding weight (r = 0.23) and days from 100 kg to breeding(r= 0.20). In two-breed cross gilts, the number of corpora lutea was correlated (P < .05) with birth weight (r = 0.25), weaning weight (r = 0.28), average daily gain (r = 0.20), age at 100 kg (r = -.20) and breeding weight (r = 0.46). The size of the litter the gilt was born or weaned in, her birth weight, average daily gain, age at 100 kg, and backfat probe were not significantly correlated with the number of embryos she had 30-days postbreeding regardless of the type of breeding of the embryo. The correlation between the gilt's weaning weight and number of embryos was significant (P<.05) for gilts with three-breed cross embryos but not for gilts with purebred or two-breed cross embryos (r = 0.35, 0.02 and 0.11, respectively). Breeding age and days from 100 kg to breeding were correlated (P<.05) with the number of embryos for gilts with two-breed cross embryos (r = 0.17 and 0.15, respectively) but these correlations were not significant for gilts with purebred embryos (r = -.13 and -.05, respectively) or for gilts with three-breed cross embryos (r = -.05 and 0.14, respectively). The correlation between breeding weight and number of embryos was significant for gilts with two-breed cross and three-breed cross embryos (r = 0.15 and 0.41, respectively) but not for gilts with purebred embryos (r = -.03). Ovulation rate accounted for 13.7, 5.8 and 23.0% of the variation in the number of purebred, two-breed cross and three-breed cross embryos, respectively (P < .05).
Influence Of Nutritional Regime On Age At Puberty In Gilts, P. J. Cunningham, C. H. Nabor, Dwane R. Zimmerman, E. R. Peo, Jr.
Influence Of Nutritional Regime On Age At Puberty In Gilts, P. J. Cunningham, C. H. Nabor, Dwane R. Zimmerman, E. R. Peo, Jr.
Department of Animal Science: Faculty Publications
Age at puberty was determined for 205 Gene Pool gilts; 68 fed a 10% protein diet (HLC) consisting of high-lysine corn, minerals and vitamins and 137 fed a 14% protein corn soybeam meal diet (CS). Gilts fed the CS diet reached puberty 18.7 days earlier than gilts fed the HLC diet. Use of post-weaning daily gain as a covariable reduced the difference between diets to 9 days. The pooled within diet regression of age at puberty on post-weaning gain was -22.75 days per kilogram. The correlation between pubertal age and daily gain was significantly higher on the HLC diet (-.30 …
Effect Of Dietary Calcium And Phosphorus Level Upon Calcium, Phosphorus And Nitrogen Balance In Swine, P. E. Vipperman, Jr., E. R. Peo, Jr., P. J. Cunningham
Effect Of Dietary Calcium And Phosphorus Level Upon Calcium, Phosphorus And Nitrogen Balance In Swine, P. E. Vipperman, Jr., E. R. Peo, Jr., P. J. Cunningham
Department of Animal Science: Faculty Publications
Three metabolism trials were conducted to determine the effects of dietary calcium and phosphorus level upon calcium, phosphorus and nitrogen balance in growing swine. The nine pigs in each trial averaged 22.6, 25.2 and 26.5 kg initially for trials 1, 2 and 3, respectively. The diets contained three levels of calcium and three levels of phosphorus and were rotated among the pigs in the three trials. Feed intake was adjusted to metabolic size.
Reproductive Efficiency Of Purebred And Crossbred Dairy Cattle, R. E. Mcdowell, J. A. Velasco, L. Dale Van Vleck, J. C. Johnson, G. W. Brandt, B. F. Hollow, B. T. Mcdaniel
Reproductive Efficiency Of Purebred And Crossbred Dairy Cattle, R. E. Mcdowell, J. A. Velasco, L. Dale Van Vleck, J. C. Johnson, G. W. Brandt, B. F. Hollow, B. T. Mcdaniel
Department of Animal Science: Faculty Publications
Nine measures related to breeding efficiency were used for comparisons among purebred Ayrshires, Brown Swiss, Holsteins, and Jerseys and between purebreds and 32 crossbred groups representing 2-breed, 3-breed, 5/8, and backcrosses by purebred sires and progeny of crossbred sires. There were four herds with Holsteins common to all, Brown Swiss and Jerseys in three herds and Ayrshires in one herd. Four 2-breed, two 3-breed, and two backcross groups were common to two or more herds. Among purebreds, breed effects were significant in 16 of 72 tests, but there was no consistent trend favoring one breed. Generally, Jerseys were better than …
Evaluation Of Purebreds And Two-Breed Crosses In Swine: Reproductive Performance, R. K. Johnson, I. T. Omtvedt
Evaluation Of Purebreds And Two-Breed Crosses In Swine: Reproductive Performance, R. K. Johnson, I. T. Omtvedt
Department of Animal Science: Faculty Publications
The data included records on 440 purebred sows and gilts of Duroc, Hampshire and Yorkshire breeding mated in all combinations to produce purebred and two-breed cross litters. A total of 119 purebred gilts (39 with purebred litters and 80 with crossbred litters) were slaughtered 30-days postbreeding and their reproductive tracts evaluated for number of corpora lutea and early embryo development. Farrowing records included 89 purebred and 161 two-breed cross litters produced at the Ft. Reno Experiment Station during the spring and fall of 1971 and the summer of 1972. Reproductive failures (females not exhibiting estrus or open at slaughter or …
Parameters Of Growth Of Holstein-Friesian Bulls, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Parameters Of Growth Of Holstein-Friesian Bulls, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Department of Animal Science: Faculty Publications
Growth records of 504 pedigree selected Holstein-Friesian bulls by 120 sires collected for progeny testing at the American Breeders Service, Inc., DeForest, Wisconsin from 1964 to 1971, were studied to determine the shape of the growth curve, relationships among body weights and growth rates at various ages and to estimate heritability of growth. Body weight and average/daily gain were consistently higher than the previous growth standards for Holstein-Friesian bulls. Bulls weighed about 480 kg at 15 months, which was 46% of average mature weight. Average daily gain ranged from 1.3 to 0.8 kg between 6 and 18 months of age. …
Effect Of Amino Acids On Non-Protein Nitrogen Utilization By G-F Swine, P. D. Platter, E. R. Peo, Jr., P. E. Vipperman, P. J. Cunningham
Effect Of Amino Acids On Non-Protein Nitrogen Utilization By G-F Swine, P. D. Platter, E. R. Peo, Jr., P. E. Vipperman, P. J. Cunningham
Department of Animal Science: Faculty Publications
Two metabolism and one feeding experiment were conducted with a total of 118 crossbred pigs to determine the effect of amino acids on non-protein nitrogen (NPN) utilization by G-F swine.
Reproductive Efficiency In Aged Female Rabbits Given Supplemental Progesterone And Oestradiol, Larry L. Larson, C. H. Spilman, H. O. Dunn, R. H. Foote
Reproductive Efficiency In Aged Female Rabbits Given Supplemental Progesterone And Oestradiol, Larry L. Larson, C. H. Spilman, H. O. Dunn, R. H. Foote
Department of Animal Science: Faculty Publications
The reproductive efficiency of twenty-eight aged does, 49 to 72 months old, was compared with that of eighteen young does, 6 to 13 months old. Fertilization rate and development in vitro of fertilized ova from rabbits induced to superovulate were not influenced by the doe's age. Ovulation rates following natural mating were only slightly reduced with age. However, the number of embryos per doe was much greater in young than in old does at 12 and 24 days post coitum. All young does had viable embryos, whereas the percentages of aged does with detectable implantation sites and viable embryos were …
Subjective Evaluation Of Teat Canal Anatomy, R. D. Appleman
Subjective Evaluation Of Teat Canal Anatomy, R. D. Appleman
Department of Animal Science: Faculty Publications
Since radiographic techniques have shown that streak canals with larger diameters tend to milk-out faster and are more susceptible to new intramammary infections, a practical visual test was sought to provide easier determination of cows with either extremely narrow (slow milking) or extra wide (susceptible to new infections) streak canals.
A subjective teat classification scheme was developed to describe five different teat-end shapes in 159 Holstein and Brown Swiss cows in the University of Nebraska dairy herd. Approximately one-fourth of the cattle had pointed or round teat ends, one-half had fiat or near flat, and one-fourth were either disk or …
Evaluation Of Purebreds And Two-Breed Crosses In Swine: Feedlot Performance And Carcass Merit , R. K. Johnson, I. T. Omtvedt, L. E. Walters
Evaluation Of Purebreds And Two-Breed Crosses In Swine: Feedlot Performance And Carcass Merit , R. K. Johnson, I. T. Omtvedt, L. E. Walters
Department of Animal Science: Faculty Publications
Feedlot performance of 941 barrows and gilts and carcass traits of 190 barrows of purebreds and crossbreds of the Duroc, Hampshire and Yorkshire breeds were evaluated for differences between purebreds and reciprocal crosses and for heterosis. Purebred and crossbred litters were farrowed contemporaneously at the Ft. Reno Experiment Station in the 1971 spring and fall farrowing seasons. Rather distinct differences between the pure breeds were evident for most traits. In general, Durocs gained weight more rapidly than Hampshires and Yorkshires while Yorkshires were the most efficient pure breed. Hampshire barrows had less backfat, more loin eye area and more total …
Relationship Between Weight And 40K Count In Steers , R. K. Johnson, L. E. Walters, J. V. Whiteman
Relationship Between Weight And 40K Count In Steers , R. K. Johnson, L. E. Walters, J. V. Whiteman
Department of Animal Science: Faculty Publications
Thirty-six Angus-Hereford steers were fed four diets of different potassium concentration for 2-week periods such that each steer received each diet for a 2-week period. The relationship between 40K count loss and weight loss during a 24-hr. shrink period was evaluated by regression analysis. At the end of each of the four feeding periods the steers ,were weighed and 40K counted unshrunk and again after 24-hr. shrink. The mean weight loss during shrink was similar for all treatments (overall mean of 22.8 kg), however the mean 40K count loss was larger for the high potassium diets than …
Effect Of A Combination Of Diethylstilbestrol And Methyltestosterone And Protein Level In The Diet On Performance And Carcass Traits In An Unselected Line Of Swine, L. E. Lucas, E. R. Peo, Jr., A. J. Svajgr
Effect Of A Combination Of Diethylstilbestrol And Methyltestosterone And Protein Level In The Diet On Performance And Carcass Traits In An Unselected Line Of Swine, L. E. Lucas, E. R. Peo, Jr., A. J. Svajgr
Department of Animal Science: Faculty Publications
Two experiments involving 372 barrows were conducted to evaluate the effects of orally administered diethylstilbestrol (DES) and methyltestosterone (MT) with varying levels of dietary protein.
Gain, Feed Conversion And Carcass Traits Of Swine Fed Under Two Nutritional Regimes, P. J. Cunningham, T. E. Socha, E. R. Peo, Jr., R. W. Mandingo
Gain, Feed Conversion And Carcass Traits Of Swine Fed Under Two Nutritional Regimes, P. J. Cunningham, T. E. Socha, E. R. Peo, Jr., R. W. Mandingo
Department of Animal Science: Faculty Publications
Data involving 505 Gene Pool boars, barrows and gilts and 126 Hampshire boars and gilts fed two nutritional diets were presented. One diet consisted of high lysine corn, minerals and vitamins (10% protein) while the other diet was a 14% protein corn-soy diet.
Factors For Extending In-Progress Lactation Records To A 305-Day Equivalent, Jeffrey F. Keown, L. Dale Van Vleck
Factors For Extending In-Progress Lactation Records To A 305-Day Equivalent, Jeffrey F. Keown, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Paper for Presentation at the 64th Annual Meeting of the American Society of Animal Science. The data consisted of 204,558 complete Holstein lactations in 2,100 herds compiled by the New York Dairy Records Processing Laboratory from 1959 to 1969. All lactation records had to have a 9th or 10th test day present to be regarded as complete. The generalized least squares analysis used a model including effects due to the mean, herd-year and season-age-stage of freshening which were assumed to be fixed. The error term included the random effects due to the cow and residual. Generalized least squares estimates for …
Reproductive Efficiency And Viability In Two Bos Indicus And Two Bos Taurus Breeds In The Tropics Of India And Colombia, L. (Lemka) Hamed, R. E. Mcdowell, L. Dale Van Vleck, H. Guha, J. J. Salazar
Reproductive Efficiency And Viability In Two Bos Indicus And Two Bos Taurus Breeds In The Tropics Of India And Colombia, L. (Lemka) Hamed, R. E. Mcdowell, L. Dale Van Vleck, H. Guha, J. J. Salazar
Department of Animal Science: Faculty Publications
Records from two herds in India and two in Columbia representing respectively two breeds of Bos indicus (Hariana and Deshi) and two Bos taurus breeds—Blanco Orejinegro (BON) and Costeño Con Cuernos (CCC) were evaluated for breeding efficiency and viability. Average age at first calving was 52.1, 46.3, 39.5 and 40.7 months for Hariana, Deshi, CCC and BON. Season of birth did not influence age at calving. Ranking for calving interval was similar, average 479, 418, 396 and 382 days with season effects significant (P<.05) for only Deshi. BON and CCC had fewer days open but much shorter lactation periods, average 73 and 157, thus days carried calf in lactation were similar for all breeds. Percent of time dry per calving interval was high for all breeds, 44.2, 36.7, 64.1 and 81.0 for Hariana, Deshi, BON and CCC. Average annual mortality of females by 12 months of age was 23.6% for Hariana, 17.0% Deshi and 27.0% BON. In the same herds 46.4%, 51.1% and 49.0% of females born alive lived to first calving and annual losses among cows were 18.0%, 17.0%, and 21.0%; therefore, affording little opportunity for selection among females. Temperament, as determined by response to the milking process with and without the calf present, showed all the breeds were similar in this respect. Environmental effects were most important for all traits but genetic differences were indicated for age at first calving and milk yield. On a theoretical basis little gain could be expected in net dairy merit from crosses between the Columbian and Indian breeds.
Genetic Aspects Of Beef Production Among Holstein-Friesians Pedigree Selected For Milk Production, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Genetic Aspects Of Beef Production Among Holstein-Friesians Pedigree Selected For Milk Production, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Department of Animal Science: Faculty Publications
To explore the potential of cattle to produce both milk and beef, the genetic aspects of beef production among Holstein-Friesian bulls pedigree selected for milk were studied. The data included growth records of 504 bulls (DPT) by 120 sires (SPT) pedigree selected for progeny testing by American Breeders Service, 1964 to 1971. DPT bulls with proofs had an average predicted difference for milk (PMD) of +180 kilograms. The daughter average was 7,273 kg per lactation under varying herd conditions. Sires accounted for 10% of the variation in average daily gain (ADG), 10% in daily gain per 100 kg body weight …
Simultaneous Selection For Milk And Beef Production Among Holstein-Friesians, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Simultaneous Selection For Milk And Beef Production Among Holstein-Friesians, L. L. Calo, R. E. Mcdowell, L. Dale Van Vleck, P. D. Miller
Department of Animal Science: Faculty Publications
A selection index combining milk and beef production traits, such that progress in aggregate economic value is maximized, was constructed for Holstein bulls. The index for milk was IM = 1.11X1 + .997X2 while the index for beef trait was IB = .008X1 + .619X2 where X1 is the daughters' average lactation yield (kg) and X2, bulls' body weight at 15 mo (kg).
The relative genetic progress from simultaneous selection for milk and beef traits with different emphasis was estimated. Expected genetic progress in beef production (body weight at 15 mo) …
Importance Of Different Levels Of Potassium In The Diet On Whole-Body 40K Count And Muscle And Blood Potassium , R. K. Johnson, L. E. Walters, J. V. Whiteman
Importance Of Different Levels Of Potassium In The Diet On Whole-Body 40K Count And Muscle And Blood Potassium , R. K. Johnson, L. E. Walters, J. V. Whiteman
Department of Animal Science: Faculty Publications
The influence of three levels (1.31, 1.03 T and 0.29% K) of dietary potassium on 40K count, blood serum and muscle tissue potassium was determined using 36 crossbred Angus-Hereford steers. A balanced 3 x 3 latin square experimental design was utilized which allowed estimates of carry-over effects of diets to be evaluated. Diets were fed for 2-week periods and appropriate samples and measurements were collected at 14-day intervals over a 60-day period. Measurements were made on steers unshrunk and after 24 hr. off feed and water. Carry-over effect means were nonsignificant for each trait. The steers on the high …
Extending Lactation Records In Progress To 305-Day Equivalent, J. F. Keown, L. Dale Van Vleck
Extending Lactation Records In Progress To 305-Day Equivalent, J. F. Keown, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The data consisted of 204,558 complete Holstein lactations in 2,100 herds compiled by the New York Dairy Records Processing Laboratory from 1959 to 1969 All lactation records had to have a 9th or 10th test day to be complete. The generalized least squares analysis used a model including mean, herd-year, and season-age-stage as fixed effects. The error term included random effects of con, and residual variation. Means for specified stages of lactation for milk and fat were estimated for lactations 1, 2, 3, and 4 or greater which were grouped by age of freshening, two age groups for the first …
Association Of Type Traits With Reasons For Disposal, L. Dale Van Vleck, H. D. Norman
Association Of Type Traits With Reasons For Disposal, L. Dale Van Vleck, H. D. Norman
Department of Animal Science: Faculty Publications
Reasons for disposal of 3,475 cows from 188 New York Holstein herds were compared with type appraisal and milk yield in first lactation to study the relationship between type traits measured early in life and later reasons for disposal. Reasons for disposal were grouped as production (32%), udder (22%), reproduction (27%), inabilities or disease (8%), workability (3%), type (3%), and other (5%). Few traits measured before 49 months of age had any significant value in predicting the reason for a cow's eventual disposal. These results in addition to earlier studies of heritability suggest that type traits measured in the first …
Potential Of Deshi Cattle Of India For Dairy Production, S. K. Moulick, R. E. Mcdowell, L. Dale Van Vleck, H. Guha
Potential Of Deshi Cattle Of India For Dairy Production, S. K. Moulick, R. E. Mcdowell, L. Dale Van Vleck, H. Guha
Department of Animal Science: Faculty Publications
There were 1,405 lactation records of 336 cows at the Central Livestock Research- cum-Breeding Station, Haringhata, India from 1958 to 1968 used to estimate the potential dairy merit of Deshi cattle. This breed is native to northeast India and one of the smallest breeds in India (mature females 200 kg and males 250 kg).
Averages and standard deviations for milk yield (exclusive of that suckled), age of first calving, calving interval, lactation length, days open, and days dry were 412 ± 178 kg, 44.5 ± 6.8 months, 419 ± 90 days, 264 ± 81 days, 135 ± 86 days, and …
A Biopsy Technique For Sampling The Gracilis Muscle In The Baby Pig, B. D. Moser, E. R. Peo, Jr., D. R. Zimmerman, P. J. Cunningham
A Biopsy Technique For Sampling The Gracilis Muscle In The Baby Pig, B. D. Moser, E. R. Peo, Jr., D. R. Zimmerman, P. J. Cunningham
Department of Animal Science: Faculty Publications
In research it is often desirable to measure body composition at different stages of growth. Ideally, if the same animal could be sampled several times during the growing-finishing period, critical information about tissue growth could be obtained. Thus, the development of a simple procedure to obtain tissue samples would be an asset to the researcher.
Comparison Of Estimated Daughter Superiority From Pedigree Records With Daughter Evaluation, L. Dale Van Vleck, H. W. Carter
Comparison Of Estimated Daughter Superiority From Pedigree Records With Daughter Evaluation, L. Dale Van Vleck, H. W. Carter
Department of Animal Science: Faculty Publications
Daughter superiorities of 240 Holstein bulls of the American Breeders Service and Eastern Artificial Insemination Cooperative (EAIC) were estimated from records of paternal sisters of the sire, dam's records, and records of daughters of the maternal grandsire. Estimated daughter superiority (EDS) was then compared with the U.S. Department of Agriculture's predicted difference for American Breeders Service bulls and with the Northeast Sire Comparison for EAIC bulls. The regression equation on estimated daughter superiority was [-84 + .561(EDS)] kg for American Breeders Service bulls and [-227 + .654(EDS)] kg for EAIC bulls. The response is not as large as theoretically predicted …
Estimation Of Heritability Of Threshold Characters, L. Dale Van Vleck
Estimation Of Heritability Of Threshold Characters, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Many traits of dairy cattle such as disease resistance and type breakdown scores may have an underlying distribution of values which are approximately normal but must be measured on a yes or no basis. Theory from literature suggests that heritability estimated from such binomial data is only z2/p(1-p) as large as heritability if it could be measured on the normal scale where z is the ordinate on the normal distribution at the threshold point corresponding to a fraction p of the population having the character. Data were generated from a pseudo-normal distribution to test this theory for estimates …