Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Bases de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Anim Physiol Anim Nutr (Berl) ; 107(1): 12-27, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35119129

RESUMO

Our objective was to determine the effects of chemical structure, amount, and site of infusion of long-chain fatty acids (LCFA) in lactating dairy cows. Six multiparous Holstein cows were used in a 6 × 6 Latin square design with 21-d periods. During d 1 to 14, 250 g/d of LCFA and during d 15 to 21, 500 g/d of LCFA were infused continuously into either the rumen or abomasum. Treatments were 1) Control (CONT); 200 g/d of meat solubles plus 12 g/d of Tween 80 in 10 L of water, administered half in the rumen and half in abomasum; 2) control plus mostly saturated LCFA into the abomasum (SFAA); 3) control plus mostly saturated LCFA into the rumen (SFAR); 4) control plus soy (mostly unsaturated LCFA) free fatty acids (FFA) into the abomasum (UFAA); 5) control plus soy triglycerides (TG) into the abomasum (TGA); and 6) control plus soy TG into the rumen (TGR). The first 10 d of each period were for adaptation and washout from the previous treatment. The diet consisted of 30% (dry matter basis) corn silage, 20% alfalfa silage and 50% concentrate. Cows infused with UFAA had lower dry matter intake and milk yield than those infused with SFAA or TGA and reductions were greater at the higher infusion amount. Milk fat yield was decreased by UFAA relative to other treatments. Unsaturated LCFA decreased milk fat yield more than saturated LCFA. All LCFA treatments decreased short- and medium-chain FA in milk relative to CONT, with greatest decreases for UFAA. Apparent total tract digestibilities of nutrient fractions were decreased by UFAA compared with TGA and SFAA and tended to be lower at the higher infusion amount. Apparent digestibility of total fatty acids (FA) was greater for SFAR than for SFAA. Plasma glucagon-like peptide-1 was greater for cows infused with UFAA than SFAA or TGA and increased at the higher amount. Plasma cholecystokinin was greater for cows infused with LCFA compared with CONT. Postruminal unsaturated FFA reduced intake and digestibility of nutrients and FA compared with postruminal TG infusion; saturated FA did not decrease dry matter intake or disrupt nutrient digestion. Glucagon-like peptide-1 may be involved in regulation of feed intake by long-chain fatty acids.


Assuntos
Ácidos Graxos , Lactação , Feminino , Bovinos , Animais , Ácidos Graxos/metabolismo , Lactação/fisiologia , Abomaso , Rúmen/fisiologia , Esterificação , Digestão , Leite/química , Ácidos Graxos não Esterificados , Dieta/veterinária , Triglicerídeos/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia
2.
Am J Vet Res ; 69(12): 1587-94, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19046005

RESUMO

OBJECTIVE: To identify any adverse effects on health or performance in young dairy calves fed clinoptilolite mixed with milk replacer. ANIMALS: 26 male Holstein calves (1 to 7 days old). PROCEDURES: Twice daily for 28 days, calves were fed milk replacer with no clinoptilolite (control group; n=8), 0.5% clinoptilolite (low-dosage group; 9), or 2% clinoptilolite (high-dosage group; 9); each calf consumed approximately 12% of its body weight (based on the replacer solids in the milk replacer mixture)/d. For each calf, subjective health assessments, weight and rectal temperature measurements, and CBC and serum biochemical analyses were performed at intervals. All calves underwent necropsy. RESULTS: 2 calves were euthanized during the experiment because of bronchopneumonia or enteritis. Body weight and average daily gain did not differ among treatment groups. The percentage of monocytes and serum total protein concentration in the low-dosage group were higher than values in the control and high-dosage groups. Compared with values for either clinoptilolite-treated group, BUN concentration was greater in the control group. Serum globulin concentration differed significantly among groups (2.77, 2.50, and 2.36 g/dL in the low-dosage, control, and high-dosage groups, respectively). At necropsy, gross lesions associated with clinoptilolite treatment were not detected in any of the calves. CONCLUSIONS AND CLINICAL RELEVANCE: Even under stressful conditions, clinoptilolite fed at low or high dosages did not affect the performance of dairy calves and had no negative effect on WBC count and blood metabolite concentrations and enzyme activities. Clinoptilolite ingestion was not associated with treatment-specific gross changes.


Assuntos
Doenças dos Bovinos/induzido quimicamente , Substitutos do Leite/química , Zeolitas/efeitos adversos , Ração Animal/efeitos adversos , Animais , Bovinos , Indústria de Laticínios , Imunização Passiva , Imunoglobulinas/sangue , Masculino
3.
Physiol Genomics ; 27(1): 29-41, 2006 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-16757553

RESUMO

Liver metabolism and health in dairy cows during the periparturient period are affected by plane of nutrition prepartum. Long-term adaptations in hepatic gene expression are important for complete understanding of liver function. We examined temporal gene expression profiles during the dry period and early lactation in liver of Holstein cows fed moderate dietary energy ad libitum or restricted during the entire dry period using a microarray consisting of 7,872 annotated cattle cDNA inserts and quantitative RT-PCR. We identified 85 genes with expression patterns that were affected by level of energy intake prepartum over time. Restricted energy intake prepartum resulted in more pronounced upregulation of genes with key functions in hepatic fatty acid oxidation (CPT1A, ADIPOR2), gluconeogenesis (PC), and cholesterol synthesis (SC4MOL). Ad libitum feeding upregulated a number of genes associated with liver triacylglycerol synthesis (DGAT1) and proinflammatory cytokines (TNFAIP3). Genomic responses to ad libitum feeding were accompanied by increased incorporation of palmitate to esterified products in vitro and increased liver triacylglycerol concentration in vivo. Overall, gene expression profiles due to plane of nutrition prepartum partly explained differences in rates of liver palmitate metabolism, blood serum metabolite concentrations, and liver tissue triacylglycerol concentration. Our data show that moderate overfeeding of energy in the dry period, in the absence of obesity, results in transcriptional changes predisposing cows to fatty liver and perhaps compromising overall liver health during the periparturient period. In this context, controlled energy intake may confer an advantage to the cow by triggering hepatic molecular adaptations well ahead of parturition.


Assuntos
Bovinos/metabolismo , Fígado/metabolismo , RNA Mensageiro/metabolismo , Animais , Restrição Calórica , Bovinos/sangue , Bovinos/genética , Indústria de Laticínios , Ingestão de Alimentos , Feminino , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Palmitatos/metabolismo , Parto , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA