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1.
J Anim Sci ; 73(10): 3173-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8617689

RESUMO

Challenges abound for academia, industry, and animal agriculture. Universities, especially land-grant universities, are losing their credibility with the public on whom they depend for support. Industries have gone and continue to go through wrenching restructuring, driven by the realities of the marketplace. On the farm and in the classrooms, laboratories, and field research stations of land-grant universities, agriculturalists face a major challenge-society's growing resistance to science and technology. Technology, especially biotechnology, has become suspect in the minds of many people. Solutions to these and other challenges for effective technology transfer in the future will not depend on a single institution, company, or program. Perhaps the most challenging issue is simply how to unite groups and individuals who have been accustomed to having their own separate programs. In the future, "business as usual"; won't work. Academia and industry are being held to new and higher standards of accountability by their clientele (customers). Academia and industry will need to join forces to increase U.S. agriculture's competitiveness in a global environment that demands that the lag time between discovery and adoption of appropriate technology be shortened.


Assuntos
Criação de Animais Domésticos/educação , Biotecnologia/educação , Indústrias/métodos , Transferência de Tecnologia , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/tendências , Animais , Biotecnologia/métodos , Biotecnologia/tendências , Indústrias/economia , Indústrias/tendências , Estados Unidos
2.
J Dairy Sci ; 69(8): 2140-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3760301

RESUMO

Forty multiparous cows beyond peak production were fed forage ad libitum behind Calan doors and grain at 1 kg/2.5 kg milk through a computer controlled feeder, and 40 similar cows were fed a total mixed ration balanced for 32 kg milk behind Calan doors ad libitum. Based on mean milk production from d 16 through 21 of a preliminary period, cows were balanced into two groups within each group of 40 cows. Both groups received the originally assigned ration during d 22 through 49. During d 50 through 77, 20 cows were switched abruptly to the other ration and 20 remained on the original. Cows fed forage and grain separately had milk yields similar to those fed total mixed ration. Dry matter intake was lower for cows fed forage and grain separately from d 22 through 49 due to reduced forage intake and was also lower from d 50 through 77 due to decreased grain intake. Four percent fat-corrected milk production efficiency was higher for cows fed forage and grain separately. Abruptly changing cows from one feeding system to another did not influence milk yield, milk composition, or body weight gain. The computer controlled feeder system is an effective method to allot grain according to milk production requirements in freestall housing.


Assuntos
Bovinos/fisiologia , Dieta , Lactação , Análise de Variância , Ração Animal , Animais , Peso Corporal , Computadores , Feminino , Leite/análise , Gravidez
3.
J Dairy Sci ; 69(7): 1871-83, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3745586

RESUMO

Holstein calves were assigned to one of three regimens from d 4 to 35 of age, then abruptly weaned (program 1): A) conventional, all-milk protein milk replacer fed individually twice daily; B) ad libitum feeding of cold, acidified milk replacer to calves housed and fed individually in pens, and C) same as B, except calves were housed and fed in group pens. From d 36 of age to 136 kg of body weight calves were in group pens by treatment. Program 2 utilized the same treatments; however, acidified milk replacer calves were gradually weaned starting d 22 of age. For program 1, calves fed acidified milk replacer for ad libitum intake consumed more dry matter from liquid and less from grain than those fed conventionally. Calves fed acidified milk replacer showed improved gains of 8.7 and 8.4 kg up to d 35 of age. For program 2, dry matter intake from liquid was higher, and grain was lower for calves fed acidified milk replacer; however, differences were not as large as in program 1. Body weight gains were 1.1 and 2.8 kg higher for calves fed acidified milk replacer through d 35 of age. No mortality occurred with either program during preweaning. In both programs, fecal consistency was more fluid for calves fed acidified milk replacer; however, days calves were treated were less. Regardless of preweaning program, calves on all treatments reached 136 kg of body weight in approximately the same number of days.


Assuntos
Ração Animal , Bovinos/crescimento & desenvolvimento , Leite , Animais , Alimentos Formulados , Concentração de Íons de Hidrogênio , Desmame
4.
J Dairy Sci ; 69(3): 734-44, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3711405

RESUMO

One hundred fifty-six Holstein cows were balanced prior to drying off to one of three diets offered during the dry period (dry matter basis): A) forage only (50% corn silage:50% alfalfa silage), B) forage as A plus a standard dairy grain mix (1.73% calcium), and C) same as B except a low calcium grain mix (.35% calcium). Grain feeding started 3 wk prepartum. Cows from each dry treatment were assigned to one of two treatments during the first 21 d postpartum: total mixed ration (dry matter basis); 50% grain:50% corn silage; or 50% grain:25% corn silage:25% alfalfa silage. Dry period feeding program had no effect on postpartum dry matter intake, milk yield, or composition. Prepartum grain feeding resulted in increased body weight gain during the last 3 wk of the dry period. Feeding corn silage postpartum as the sole forage resulted in higher dry matter intakes (15.0 vs. 14.1 kg/d), milk production (31.3 vs. 29.7 kg/d), and less body weight loss (36 vs. 58 kg) during the first 21 d postpartum than feeding a 50% corn silage:50% alfalfa silage mixture. However, differences varied depending on dry cow feeding program. All dry cow treatments resulted in a high incidence of milk fever (11.5, 11.5, and 15.5% for A, B, and C, respectively). Dry cow rations containing as little as 50% alfalfa silage appear to predispose cows to increased incidence of milk fever.


Assuntos
Ração Animal , Bovinos/fisiologia , Comportamento Alimentar/fisiologia , Lactação , Animais , Peso Corporal , Feminino , Leite/análise , Gravidez
5.
J Dairy Sci ; 67(2): 319-33, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6715627

RESUMO

Holstein calves (159) were assigned alternately to one of seven regimens through, day 45: nurse dam for 12 to 24 h, dam's milk to 96 h, milk replacer with all milk protein; low (less than or equal to 45 mg/ml) immunoglobulin colostrum to 96 h, then either colostrum, replacer with all milk, or soy protein; high (less than 60 mg/ml) immunoglobulin colostrum to 96 h, then replacer all milk; replacer all milk protein from birth; or saleable milk from birth. Colostrum immunoglobulin was estimated by colostrometer and colostrum was frozen. Starter and water were offered free choice on day 5. Calves deprived of colostrum gained poorly and suffered severe and long scour episodes and high mortality. No differences of body weight gains were observed between calves that nursed compared with those hand fed. Calves fed colostrum with high immunoglobulin gained weight from birth to day 4 while those fed low lost weight. Overall severity and duration of scours were less for calves fed colostrum with high compared to low immunoglobulin. Calves fed undiluted colostrum (5 to 45 days) had more severe scours longer than those fed milk replacer. Serum protein and immunoglobulin were higher for calves hand fed high immunoglobulin compared to low immunoglobulin colostrum or nursing at 12 to 24 h and 4 days after birth. A positive relationship developed between serum protein and immunoglobulin at 12 h to 24 h, 4 and 11 days. Mortality was low for all calves receiving colostrum.


Assuntos
Proteínas Sanguíneas/metabolismo , Peso Corporal , Bovinos/fisiologia , Colostro , Ração Animal , Animais , Animais Recém-Nascidos , Animais Lactentes , Colostro/imunologia , Feminino , Imunoglobulinas/análise , Masculino , Leite
6.
J Dairy Sci ; 66(12): 2533-43, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6668377

RESUMO

Seventy-two Holstein cows (16 first lactation) were assigned to four treatments: A) normal-grind limestone (800 to 1000 mu) added to provide .77% calcium (total ration dry basis); B) fine-grind limestone (less than 150 mu) at .77% calcium; C) normal-grind at 1.15% calcium; and D) fine-grind limestone at 1.15% calcium. Cows fed diets containing .77% calcium had higher percent milk fat and fat yield than those fed 1.15% calcium diets, and cows fed fine-grind limestone had greater percent fat and fat yield than those fed normal-grind limestone. Four percent fat-corrected milk was higher for cows fed .77% calcium diets. Trends were similar for heifers in first lactation. Dry matter intake was higher for cows fed .77% calcium diets, and nutrient efficiency for milk synthesis favored cows fed fine-grind 1.15% calcium. Fecal pH was higher during wk 4 on treatment for cows fed high calcium diets; however, 8 wk were not different. Fecal starch and calcium and phosphorus in plasma were not different between treatments: however, heifers fed fine-grind 1.15% calcium showed a decrease of fecal starch with time.


Assuntos
Carbonato de Cálcio/administração & dosagem , Cálcio da Dieta/administração & dosagem , Bovinos/fisiologia , Lactação , Leite/metabolismo , Animais , Peso Corporal , Feminino , Metabolismo dos Lipídeos , Proteínas do Leite/metabolismo , Tamanho da Partícula , Gravidez
7.
J Dairy Sci ; 66(5): 1108-18, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6875059

RESUMO

During 3 yr, 289 Holstein cows prior to being dried off were assigned randomly to one of three diets: all long hay, 50% hay and 50% corn silage, and limit-fed corn silage plus 1.1 kg liquid protein supplement added per cow per day. Body weights, condition scores, and calving difficulties were recorded. Calf weights were recorded at birth. All cows were distributed across eight postpartum experiments. Body condition was similar for all cows at termination of dry period. Cows fed limited corn silage plus liquid supplement gave birth to heavier calves and had greater calving difficulty. Diet for dry period had little effect on health in the subsequent lactation. Cows fed long hay while dry consumed more dry matter, produced more milk with lower milk fat percent, and were not different for 4% fat-corrected milk compared to cows fed the other two diets in dry period. Days open were greater for cows fed long hay while dry. In general, as long as the ration is nutritionally balanced and fed in amounts to achieve or maintain adequate body condition, forage programs ranging from all hay to all corn silage can be fed successfully during the dry period.


Assuntos
Bovinos/fisiologia , Dieta , Lactação , Leite/metabolismo , Prenhez , Reprodução , Animais , Peso Corporal , Doenças dos Bovinos/epidemiologia , Feminino , Gravidez
8.
J Dairy Sci ; 66(3): 505-13, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6302147

RESUMO

Eighty animals (16 first lactation) were assigned alternately at calving to one of four treatments: A) corn silage, B) corn silage + 1.5% sodium bicarbonate and .5% magnesium oxide in the grain mix, C) 50% hay crop silage and 50% corn silage, and D) 50% hay crop silage and corn silage plus 1.5% sodium bicarbonate and .5% magnesium oxide. All rations contained 50% forage and 50% concentrate (dry) fed as a total mixed ration. During the first 8 wk of lactation no differences were detected in mean performance or in weekly patterns for forage programs alone or buffer treatments alone on average daily intake of dry matter, body weight loss, milk yield, or composition. Addition of buffers to hay crop silage and corn silage rations resulted in a milk yield profile with a smaller increase beyond wk 3 postpartum. Cows fed all corn silage rations yielded more milk on the average than cows on hay crop silage and corn silage, regardless of buffer treatments. From wk 9 through 12 of lactation, buffers either were added or withdrawn. Addition or withdrawal of buffers did not alter significantly patterns of milk yield or composition.


Assuntos
Bicarbonatos/farmacologia , Bovinos/fisiologia , Lactação , Óxido de Magnésio/farmacologia , Leite/metabolismo , Animais , Bicarbonatos/administração & dosagem , Feminino , Aditivos Alimentares , Óxido de Magnésio/administração & dosagem , Gravidez , Silagem , Bicarbonato de Sódio , Zea mays
9.
Cornell Vet ; 70(2): 113-24, 1980 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7408493

RESUMO

A study was made of the relative effectiveness of including various feed supplements or selenium injections on increasing the blood level of selenium in pregnant Holstein cows. The dietary treatment included the addition of soft coal fly ash, western grown grains, high selenium sweet clover or sodium selenite to the rations. Whereas each of the treatments caused a progressive increase in blood selenium the addition of 4% by weight of fly ash to the ration raised the concentration of selenium in blood the highest. Increases in the concentration of selenium in milk as a result of the treatments were very small.


Assuntos
Bovinos/sangue , Selênio/sangue , Administração Oral , Ração Animal/análise , Animais , Bovinos/fisiologia , Feminino , Injeções Intramusculares , Leite/análise , Gravidez , Selênio/administração & dosagem , Selênio/análise , Triticum/análise
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