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Full-Text Articles in Dairy Science
Resynchronization Of Ovulation And Conception In Nonpregnant Dairy Cows And Heifers (2006), M.A. Portaluppi, D.E. Tenhouse, Jeffrey S. Stevenson
Resynchronization Of Ovulation And Conception In Nonpregnant Dairy Cows And Heifers (2006), M.A. Portaluppi, D.E. Tenhouse, Jeffrey S. Stevenson
Kansas Agricultural Experiment Station Research Reports
Our objectives were to determine various factors influencing upfront single and multiple ovulation in response to GnRH in a timed arti-ficial insemination (TAI) protocol and subse-quent fertility after altering timing of the sec-ond GnRH injection and AI relative to PGF2αinjection. Replacement heifers (n = 86) and 613 lactating cows previously inseminated were diagnosed not pregnant at biweekly in-tervals to form 77 breeding clusters spanning 36 months. At not-pregnant diagnosis (day 0), females received 100 μg of GnRH, and they received 25 mg of PGF2α7 days later. Females in 2 treatments received GnRH 48 hr (G48) after PGF2αinjection and TAI at …
Delaying Injection Of Prostaglandin F2Α In An Ovsynch Protocol (2006), M.A. Portaluppi, D.E. Tenhouse, Jeffrey S. Stevenson
Delaying Injection Of Prostaglandin F2Α In An Ovsynch Protocol (2006), M.A. Portaluppi, D.E. Tenhouse, Jeffrey S. Stevenson
Kansas Agricultural Experiment Station Research Reports
Our objective was to determine whether delaying the PGF2αinjection by 24 or 48 hr after the first GnRH injection in an Ovsynch protocol (from a standard 7 days) altered ovar-ian characteristics in lactating dairy cows. Es-trous cycles were synchronized in 36 Hol-steins after removal of a progesterone-releasing controlled internal drug release (CIDR) insert and injection of PGF2α. On day 6 of the estrous cycle, cows were administered 100 μg of GnRH (81 ± 2 days postpartum) and assigned randomly to receive a treatment in-jection of PGF2α7, 8, or 9 days later. Timed artificial insemination (TAI) was performed at 48 hr …
Fresh Cow Health Issues, Jerry D. Olson
Fresh Cow Health Issues, Jerry D. Olson
Kansas Agricultural Experiment Station Research Reports
The post-calving period is a critical time in a cow's life. The first few weeks post-calving pose the highest risk period for a number of diseases including milk fever, mastitis, metritis, pneumonia, retained fetal membranes, ketosis, and displaced abomasum. Post-calving diseases adversely affect dry matter intake, peak milk production, and reproductive performance, in addition to increasing the risk of involuntary culling and death. Consequences of disease can be costly. The ideal strategy is to minimize losses associated with disease by preventing their occurrence. However, even with the best management practices in place, it is impossible to prevent all post-calving diseases. …
Transition Cow Nutrition And Management, John E. Shirley
Transition Cow Nutrition And Management, John E. Shirley
Kansas Agricultural Experiment Station Research Reports
Dairy cows are generally provided with a 60-day dry period. The first part of the dry period is called the "far-off dry period" beginning at dry off and continuing until 21 days before projected calving date. The second part of the dry period is called the "close-up dry period" beginning at 21 days before projected calving date and ending at parturition. Diets formulated for far-off dry cows are generally high in forage and are designed to support body maintenance and fetal growth. Rumen function and microbial populations adjust to these diets by the end of the far-off period and require …
Changes In Ruminal Microbial Populations In Transition Dairy Cows, A.F. Park, Evan C. Titgemeyer, R.C. Cochran, J.M. Defrain
Changes In Ruminal Microbial Populations In Transition Dairy Cows, A.F. Park, Evan C. Titgemeyer, R.C. Cochran, J.M. Defrain
Kansas Agricultural Experiment Station Research Reports
We used four ruminally fistulated, multiparous, pregnant Holstein cows to delineate microbial adaptations in dairy cows as they experienced the transition from one lactation to the next. Diets consisted of typical far-off and close-up diets, a late lactation diet containing wet corn gluten feed (20% DM) and an alfalfa hay-corn silage based early lactation diet. Calculated NEL (Mcal/lb), measured crude protein (%), and diet digestibilities (%; based on steers fed at 2% of BW) were: 0.78, 18.7, 74.1; 0.70, 11.5, 66.2; 0.74, 15.6, 71.0; 0.73, 18.4, 70.7 for late lactation, far-off dry, close-up dry, and early lactation, respectively. Microbial samples …
Characteristic Changes Of Ruminal Fermentation In Transition Dairy Cows (2002), A.F. Park, Evan C. Titgemeyer, R.C. Cochran, J.M. Defrain
Characteristic Changes Of Ruminal Fermentation In Transition Dairy Cows (2002), A.F. Park, Evan C. Titgemeyer, R.C. Cochran, J.M. Defrain
Kansas Agricultural Experiment Station Research Reports
Four-ruminally fistulated, multiparous, pregnant Holstein cows were used to delineate changes in ruminal fermentation in dairy cows as they experienced the transition from one lactation to the next. Diets consisted of typical far-off and close-up diets, a late lactation diet containing wet corn gluten feed (20% DM) and an alfalfa hay-corn silage based early lactation diet. Calculated NEL (Mcal/lb), measured crude protein (%), and diet digestibilities (%; based on steers fed at 2% of BW) were: 0.78, 18.7, 74.1; 0.70, 11.5, 66.2; 0.74, 15.6, 71.0; 0.73, 18.4, 70.7 for late lactation, far-off dry, close-up dry, and early lactation diets, respectively. …