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1.
J Dairy Sci ; 103(5): 4681-4690, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32197846

RESUMO

Regrouping occurs when dairy cows are moved between pens, and this can negatively affect cow behavior and production. Pen changes occur frequently around calving, a time when cows are vulnerable to health problems. Regrouping cows along with a familiar conspecific after calving may make social integration easier, but little work has tested this hypothesis. The objective of this study was to compare lying behavior, feeding behavior, social behavior, and fecal cortisol metabolite concentrations (a physiological indicator of stress) between cows regrouped individually and cows regrouped with a familiar partner after calving. Holstein (n = 8) and Jersey (n = 26) cows were monitored from approximately 2 wk before until 7 d after calving. Cows were held in 1 of 2 identical maternity pens until they calved. After calving, cows were held in a transition pen for 3 d before being regrouped into the main lactation pen (regrouping of interest). On d 3 postpartum, cows were assigned to a treatment, balancing for parity and breed: regrouped into the lactation pen alone (individual; n = 17) or with a familiar partner (paired; n = 17). A familiar partner was defined as a cow that spent 3 d in the transition pen with the focal cow. Using live observation, we quantified the time cows spent feeding, standing or lying in the lying stalls, grooming, and standing in different locations in the pen during the 1 h immediately after regrouping. The frequency of competitive interactions at the feed bunk was also measured during this observation period. Lying behavior was monitored from 2 d before until 5 d after regrouping using a data logger. Fecal samples were collected for 5 d beginning on the day of regrouping to assess fecal cortisol metabolite concentrations (11,17-dioxoandrostane, 11,17-DOA). We found no effects of regrouping treatment on behaviors observed during the 1-h period immediately following regrouping. Cows that were regrouped with a partner had more lying bouts than cows moved individually (9.2 ± 0.4 bouts/d vs. 7.5 ± 0.4 bouts/d) and shorter lying bout durations (66.6 ± 3.9 vs. 78.1 ± 3.5 min/d); however, we also observed these differences during the day before regrouping, suggesting that the differences in lying behavior could not be explained by the regrouping treatment alone. Individually regrouped primiparous cows had higher 11,17-DOA concentrations than individually regrouped multiparous cows but we found no differences in 11,17-DOA between parities when cows were moved with a familiar partner. In addition, 11,17-DOA was higher in primiparous cows moved alone compared with primiparous cows moved with a partner. More research is needed to understand the mechanisms by which social familiarity affects behavior and the physiological stress response following regrouping; this may provide new insight into how to better transition cows into new environments.


Assuntos
Comportamento Animal , Bovinos/fisiologia , Comportamento Alimentar , Hidrocortisona/metabolismo , Animais , Indústria de Laticínios , Fezes/química , Feminino , Lactação , Paridade , Período Pós-Parto , Gravidez , Comportamento Social , Fatores de Tempo
2.
Crit Care Med ; 23(6): 1106-11, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7774223

RESUMO

OBJECTIVE: The sodium/hydrogen ion (Na+/H+) antiporter system of brain cells is responsible for reducing intracellular acid loads and regulating cellular volume. Activation of this system during reperfusion following cardiac arrest may contribute to cerebral edema and subsequent brain damage. Therefore, we wished to determine whether administration of methyl isobutyl amiloride, a known inhibitor of the Na+/H+ antiporter system, would cross the blood brain barrier and delay the return of brain intracellular pH to normal values during reperfusion after cardiac arrest in rats. DESIGN: a) Prospective sequential evaluation of the regional brain blood flow and 3H-methyl isobutyl amiloride extraction fraction in rats; b) prospective sequential evaluation of brain intracellular pH in rats treated with methyl isobutyl amiloride compared with untreated control rats. SETTING: A research laboratory. SUBJECTS: Thirteen male Wistar rats: a) three rats to study regional brain blood flow and 3H-methyl isobutyl amiloride cerebral extraction; and b) ten rats to study the effect of methyl isobutyl amiloride on brain intracellular pH after cardiac arrest and reperfusion. INTERVENTIONS: a) Rats were injected with 14C iodoantipyrine and 3H-methyl isobutyl amiloride, and their brains were subsequently analyzed to determine regional cerebral blood flow and percent of cerebral extraction of methyl isobutyl amiloride. b) Cardiac arrest was induced with potassium chloride followed by resuscitation 7 mins later in untreated control rats and rats treated with methyl isobutyl amiloride. MEASUREMENTS AND MAIN RESULTS: a) Regional cerebral blood flow (mL/100 g/min) determined with 14C iodoantipyrine and percent of cerebral extraction of 3H-methyl isobutyl amiloride were evaluated in various regions of the brain. Mean +/- SD values were 167 +/- 15 and 7 +/- 1 for the frontal cerebral cortex; 159 +/- 10 and 7 +/- 2 for the parietal cerebral cortex, 130 +/- 17 and 8 +/- 1 for the hippocampus, 154 +/- 33 and 13 +/- 4 for the cerebellum and 166 +/- 27 and 6 +/- 1 for the striatum (mL/100 g/min). These values were determined by a dual label indicator fractionation method. b) Brain intracellular pH was measured by neutral red histophotometry after 15 mins of reperfusion following cardiac arrest. As compared with untreated control rats, methyl isobutyl amiloride-treated animals had significantly lower brain intracellular pH values after 15 mins of reperfusion. Mean +/- SD pH values were 6.78 +/- 0.18 for the rats treated with methyl isobutyl amiloride vs. normal intracellular pH of 7.11 +/- 0.07 for the untreated control rats. CONCLUSIONS: a) Methyl isobutyl amiloride crosses the blood brain barrier of rats. b) The Na+/H+ antiporter system is operative during reperfusion after cardiac arrest in rats.


Assuntos
Amilorida/análogos & derivados , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Parada Cardíaca/tratamento farmacológico , Trocadores de Sódio-Hidrogênio/efeitos dos fármacos , Amilorida/farmacocinética , Amilorida/farmacologia , Animais , Encéfalo/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Parada Cardíaca/metabolismo , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Masculino , Reperfusão Miocárdica , Estudos Prospectivos , Ratos , Ratos Wistar
3.
J Med Educ ; 60(9): 669-76, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-4032440

RESUMO

Debate over the level of indirect cost reimbursement associated with federally funded research projects continues to grow. With the increasing federal budget restraints, one recurring proposal arising from federal legislators, the executive branch, and the National Institutes of Health to cut costs and sustain direct project support has been to reduce indirect cost reimbursement. Using a system dynamics simulation model, the authors in this paper analyze the long-term economic impacts of such cutbacks on an academic medical center. The significant negative multiplier effects, due to the required diversion of institutional funds, are indicative of those that any research oriented university would experience.


Assuntos
Centros Médicos Acadêmicos/economia , Custos e Análise de Custo , Apoio à Pesquisa como Assunto/economia , National Institutes of Health (U.S.) , Pesquisa , Estados Unidos
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