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RESUMEN Objetivo. Determinar la prevalencia de cetosis bovina según las concentraciones séricas (mmol/Lt) de beta-hidroxibutirato (βHB) y estimar su asociación con enfermedades del posparto temprano en vacas lecheras. Materiales y métodos. Se llevó a cabo un estudio epidemiológico de corte transversal con información individual de los niveles sanguíneos de βHB y presentación clínica de enfermedades puerperales de n=1149 animales; además se evaluó la eficiencia de la prueba como predictora de enfermedad posparto. Posteriormente, se realizó X 2 y un modelo de regresión logística final para explorar los factores asociados con hipercetonemia. La relación entre βHB sanguíneo, la presentación de cetosis y la ocurrencia de enfermedades puerperales se calculó analizando Característica Operativa del Receptor (Receiver Operating Characteristic -ROC). Resultados. Según los niveles de -3HB, la prevalencia de cetosis fue de 7.9%, cetosis clínica 0.6% y cetosis subclínica 7.3%. La prueba fue predictora de enfermedad puerperal (LR+ del 13.6). La condición corporal ≥3.5, número de partos igual a 2 y ≥3, la presentación de retención de placenta, fiebre de leche y la enfermedad posparto, son factores de riesgo de cetosis. El análisis de la curva ROC mostró que la medición de βHB (≥1.2 mmol/Lt) en sangre sirve para diagnosticar cetosis (p<0.0001). Conclusiones. La medición de niveles sanguíneos de βB permitió determinar que la presentación de cetosis es baja, es una alerta no solamente para esta enfermedad sino para las enfermedades del posparto temprano. Los resultados de este estudio confirman lo reportado en estudios previos sobre los factores de riesgo de cetosis.
ABSTRACT Objective. Determine the prevalence of bovine ketosis based on serum concentrations (mmol/Lt) of beta-hydroxybutyrate (βHB) and estimate its association with early postpartum diseases in dairy cows. Materials and methods. An epidemiological cross-sectional study was carried out with individual information on blood levels of βHB and clinical presentation of puerperal diseases in 1149 animals; In addition, the efficiency of the test was evaluated as a predictor of postpartum disease. Subsequently, univariate analysis and a final logistic regression model were performed to explore the factors associated with hyperketonemia. The association between blood βHB, the presentation of ketosis and the occurrence of puerperal diseases was calculated by analyzing the Receiver Operating Characteristic -ROC. Results. According to βHB levels, the prevalence of ketosis was 7.9%, clinical ketosis 0.6% and subclinical ketosis 7.3%. The test was a predictor of puerperal disease (LR+ of 13.6). Body condition score ≥3.5, number of births 2 and ≥3, presentation of retained fetal membranes, milk fever and postpartum disease, are risk factors for ketosis. The analysis of the ROC curve showed that the measurement of βHB (≥1.2 mmol/Lt) in blood serves to diagnose ketosis (p<0.0001). Conclusions. The measurement of βHB blood levels allowed to determine that ketosis presentation is low, it is an alert not only for this disease but for early postpartum diseases. The results of this study confirm risk factors observed in previous studies.
Asunto(s)
Bovinos , Ácido 3-Hidroxibutírico , Periodo Posparto , Cetosis , Oportunidad RelativaRESUMEN
RESUMEN Con el objetivo de evaluar el potencial lipotropics de metionina-colina en vacas lecheras durante el periodo de transición, dosis de 20 g/d de una Fuente Comercial Protegida de la Degradación Ruminal (FCPDR) de metionina y sus combinaciones con una FCPDR de colina en dosis de 60 y 120 g/d se suministraron a vacas entre el día 260 de gestación y el día 20 posparto. Estas pastoreaban kikuyo (Cenchrus clamdestinus) y recibieron un complemento alimenticio. En los días 270 de gestación y 10 y 20 posparto se cuantificaron las concentraciones plasmáticas de ácidos grasos no esterificados (AGNES), β-Hidroxibutirato (BHB) y triglicéridos (TG), así como las concentraciones hepáticas de triacilglicéridos, de colina, carnitina total, carnitina libre y acil carnitina. Durante el preparto se presentaron los valores significativamente más altos (p < 0.05) de TG plasmáticos y los significativamente más bajos (p < 0.05) de AGNES y BHB. Las concentraciones hepáticas de TG, de colina y de las diferentes formas de carnitina no difirieron significativamente entre periodos de muestreo y no se vieron afectadas por la suplementación con metionina-colina. Por su parte, las concentraciones plasmáticas de BHB aumentaron significativamente (p < 0.05) con la suplementación conjunta de metionina y colina, lo que sugiere un aumento en la oxidación de ácidos grasos. Se concluye que con concentraciones bajas de AGNES la metionina y colina no son nutrientes limitantes para la exportación de TG desde el hígado a la sangre. Bajo esta condición no se observó lipidosis hepática y como consecuencia la suplementación con metionina-colina no ocasionó efectos significativos sobre las concentraciones hepáticas de TG.
ABSTRACT In order to evaluate the lipotropic potential of methionine-coline in dairy cows during the transition period, the effect of supplementation with 20 g / d of a Ruminal Degradation Protected Commercial Source (FCPDR) of methionine was evaluated, and their combinations with a choline FCPDR in doses of 60 and 120 g / day. Cows grazed kikuyo (Cenchrus clandestinus) and received a nutritional supplement between day 260 of gestation and day 20 postpartum. On day 270 of gestation and on days 10 and 20 postpartum blood samples and liver biopsy were taken, in which were quantified: Non-esterified Fatty Acids (NEFAS), β-Hydroxybutyrate (BHB) and Triglycerides; And hepatic concentrations of triacylglycerides, choline, total carnitine, free carnitine and acyl carnitine. The highest values (p < 0.05) of plasma triglycerides and the significantly lower values (p < 0.05) of AGNES and BHB were presented during the prepartum. Hepatic concentrations of triglycerides, choline and different forms of carnitine did not differ significantly between sampling periods, and were unaffected by methionine-choline supplementation. Plasma concentrations of BHB increased significantly (p < 0.05) with co-supplementation with methionine and choline, suggesting an increase in fatty acid oxidation. At relatively low concentrations of AGNES, methionine and choline are not limiting nutrients for the exportation of triglycerides from the liver to the blood, therefore under this condition no hepatic lipidosis was observed and consequently methionine-choline supplementation did not cause significant effects on hepatic triglyceride concentrations.
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Avaliou-se o efeito do fornecimento de monensina sódica no desempenho de vacas leiteiras em fase inicial de lactação, cuja alimentação, em sua dieta total no cocho, compôs-se em 81,4% de silagem de milho e 18,6% de concentrado, em que se fez uso de maior proporção de silagem de milho de que concentrado. Foram utilizadas 14 vacas multíparas 7/8 Holandês, aos 20±10 dias pós-parto aproximadamente, com média de 22±0,5kg vaca-1 dia-1 de leite, em delineamento de blocos casualizados, adotando-se o esquema de parcelas subdivididas no tempo, em modelo de medidas repetidas. Os tratamentos nas parcelas foram diferenciados pela presença (200mg animal-1dia-1) ou ausência da monensina na ração e, nas subparcelas, pelos diferentes períodos de avaliação. Não se observaram diferenças no consumo em matéria seca da dieta, conversão alimentar, produção de leite in natura e corrigida e peso vivo nas médias diárias de cada período. No entanto, a produção de sólidos totais foi superior para os tratamentos com o ionóforo, sinalizando que a administração da monensina sódica para vacas no início de lactação modifica o rendimento em produção de leite.
The effect on the performance of early lactation cows when supplying them with sodium monensin was evaluated, whose power in their overall diet in the trough, was composed of 81.4% of corn silage and 18.6% of concentrate in which use was made of a higher proportion of corn silage to concentrate. Fourteen multiparous 7/8 Dutch cows were used, approximately 20±10 days post-labor, with the average weight of 22±0.5kg cow-1 day-1 of lactation, in randomized blocks, adopting the scheme of subdivided portions in time and repetitive measurement model. The treatments in portions were differentiated by the presence (200mg.animal-1day-1) or absence of monensin in the food and, in the sub-portions, different evaluation periods were used. The animals were fed with their total diet in the feeder composed of 81.4% of corn silage and 18.6% of concentrate. No difference was found in the consumption of diet dry matter, alimentary conversion, in natural and corrected production of milk and live weight in the daily averages of each period. However, the production of total solids was superior for treatments with ionophore, signalizing that the administration of sodium monensin in early lactation cows changes the milk production performance.
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The aim of this study was to investigate the variations of rumen pH and fatty acids (acetic acid, propionic acid, iso-butyric acid, n-butyric acid, iso-valerianic acid, n-valerianic, caproic acid and total fatty acids) in 245 early lactating dairy cows under different temperature and humidity conditions. The animals were divided into six groups and rumen fluid was collected by rumenocentesis on 22 dairy cows in April (Group A), 33 in May (Group B), 43 in June (Group C), 48 in July (Group D), 36 in September (Group E) and 60 in October (Group F). One-way analysis of variance (ANOVA), followed by the Bonferroni’s test, showed a significant effect of environmental variations on all studied parameters (P<0.0001). Changes in studied parameters can be explained in relation to the microbial population and shift in the optima for rumen conditions associated with variations of environmental conditions. We can affirm that the microbial assemblages that underlie energy and protein supply to wild ruminant are evident especially in relation to temperature and humidity conditions.
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In early lactation dairy cattle suffer metabolic alterations caused by negative energy balance, which predisposes to fatty liver and ketosis. The aim of this study was to evaluate the metabolic condition of high yielding dairy cows subjected to three treatments for preventing severe lipomobilization and ketosis in early lactation. Fifty four multiparous Holstein cows yielding >30 L/day were divided into four groups: control (CN= no treatment), glucose precursor (PG= propylene-glycol), hepatic protector (Mp= Mercepton®), and energy supplement with salts of linolenic and linoleic faty acids (Mg-E= Megalac-E®). Treatments were administrated randomly at moment of calving until 8 weeks postpartum. Blood samples were collected on days 1, 7, 14, 21, 28, 35, 42 and 49 postpartum. Body condition score (BCS) was evaluated at the same periods and milk yield was recorded at 2nd, 4th, 5th, 6th, 7th, and 8th weeks of lactation. Concentrations of non-esterified fatty acids (NEFA), albumin, AST, ß-hydroxybutyrate (BHBA), cholesterol, glucose, total protein, urea and triglycerides were analyzed in blood samples. Cut-off points for subclinical ketosis were defined when BHBA >1.4 mmol/L and NEFA >0.7 mmol/L. General occurrence of subclinical ketosis was 24 percent during the period. An ascendant curve of cholesterol and glucose was observed from the 1st to the 8th week of lactation, while any tendency was observed with BHBA and NEFA, although differences among treatments were detected (p<0.05). BCS decreased from a mean of 3.85 at 1st week to 2.53 at 8th week of lactation (p=0.001). Milk yield was higher in the Mg-E group compared with the other treatment groups (p<0.05) Compared with the CN group, the treatments with Mp and PG did not show significant differences in blood biochemistry and milk yield. Cows receiving PG and Mg-E showed higher values of BHBA and NEFA (P<0.05), indicating accentuated lipomobilization. Supplementation with Mg-E also resulted in significant higher concentrations of cholesterol, BHBA, urea, AST and lower values of glycemia. This performance may be explained by the highest milk yield observed with this treatment. Treatments with PG and Mp did not improve milk yield, compared with control cows, but did not show metabolic evidence of ketosis, fat mobilization or fatty liver. These results suggest that treatment with Mg-E improves milk production but induces a higher negative energy balance leading to moderated lipomobilization and ketone bodies production, increasing the risk of fatty liver.
Durante o início da lactação as vacas leiteiras sofrem transtornos metabólicos causados pelo balanço energético negativo, o que predispõe a infiltração gordurosa hepática e cetose. O objetivo deste estudo foi avaliar o status metabólico de vacas leiteiras de alta produção submetidas a três tratamentos para prevenir severa lipomobilização e cetose no início da lactação. Cinquenta e quatro vacas de raça Holandesa multíparas produzindo >30 L/dia foram divididas em quatro grupos: controle (CN= sem tratamento), precursor de glicose (PG= propileno-glicol), protetor hepático (Mp= Mercepton®) e suplementação com sais de ácidos linolênico e linoléico (Mg-E= Megalac-E®). Amostras de sangue foram coletadas nos dias 1, 7, 14, 21, 28, 35, 42 e 49 do pós-parto. A condição corporal foi avaliada nos mesmos períodos e a produção de leite foi registrada nas semanas 2, 4, 5, 6, 7 e 8 de lactação. As concentrações de ácidos graxos não esterificados (AGNE), albumina, AST, ß-hidroxibutirato (BHB), colesterol, glicose, proteína total, uréia e triglicerídeos foram determinadas nas amostras de sangue. Pontos de corte para diagnosticar cetose subclínica foram definidos quando BHB >1,4mmol/L e AGNE >0,7mmol/L. A ocorrência geral de cetose subclínica foi de 24 por cento durante o período. Uma curva ascendente de colesterol e de glicose foi observada desde a 1ª até a 8ª semana de lactação, enquanto que nenhuma tendência foi observada com BHB e AGNE, embora diferenças entre os tratamentos foram detectadas (p<0,05). A condição corporal diminuiu de uma media de 3,85 na 1ª semana até 2,53 na 8ª semana de lactação (p=0,001). A produção de leite foi superior no grupo de Mg-E comparado com os demais tratamentos. Comparado com o grupo CN, os tratamentos de Mp e PG não mostraram diferenças significativas na bioquímica sanguínea nem na produção de leite (p<0,05) As vacas que receberam PG e Mg-E mostraram maiores valores de AGNE, indicando uma acentuada lipomobilização. A suplementação com Mg-E também resultou em maiores concentrações de colesterol, BHB, uréia, AST e menores valores de glicemia. Este resultado pode ser explicado pela maior produção de leite observada com este tratamento. Os tratamentos com PG e Mp não melhoraram a produção de leite, comparados ao grupo CN, mas também não mostraram evidências metabólicas de cetose, alta lipomobilização nem infiltração gordurosa hepática. Os resultados sugerem que o tratamento com Mg-E melhora a produção de leite, mas induz um balance energético negativo maior levando a moderada lipomobilização e produção de corpos cetônicos, aumentando o risco de fígado gorduroso.