RESUMEN

A cetose, conhecida também como acetonemia, é um distúrbio metabólico que afeta principalmente vacas leiteiras de alta produção. A elevação anormal de corpos cetônicos nos tecidos e fluidos corporais do animal ocorre devido a um déficit de energia. A quantidade de alimento/nutrientes ingeridos não é suficiente para suprir a demanda corporal do mesmo, assim como a eficiência reprodutiva que está diretamente ligada à saúde, condição corporal e sua capacidade de produção. Animais de alta produção possuem um desafio muito grande de aumentar a produção a cada lactação, com isso, estão susceptíveis a mudanças metabólicas, entre elas a cetose, clínica ou subclínica. Tal enfermidade ocorre devido a uma má adaptação metabólica do animal a sua nova condição de lactante. A elevada incidência de doenças uterinas no pós-parto de vacas leiteiras é responsável por inúmeros prejuízos para a atividade, principalmente pela redução da eficiência reprodutiva das vacas acometidas por infecções. Contudo, visto que a cetose subclínica prevalece nos rebanhos leiteiros de alta produção, o objetivo desta revisão de literatura é apresentar a patogenia e os efeitos que esse distúrbio metabólico têm sobre a reprodução das vacas de aptidão leiteira no após o parto, utilizando de indicadores como taxa de prenhez, taxa de concepção, retorno a ciclicidade, intervalo entre partos e intervalo entre parto e estro.(AU)

Ketosis, also known as acetonemia, is a metabolic disorder that primarily affects high-yielding dairy cows. The abnormal elevation of ketone bodies in the animal's tissues and body fluids occurs due to an energy deficit. The amount of food/nutrients ingested are not enough to supply the body's demand, as well as the reproductive efficiency that is directly linked to health, body condition and its production capacity. High production animals have a very big challenge to increase production with each lactation, therefore, they are susceptible to metabolic changes, including clinical or subclinical ketosis. Such a disease occurs due to a poor metabolic adaptation of the animal to its new lactating condition. The high incidence of uterine diseases in the postpartum period of dairy cows is responsible for numerous losses to the activity, mainly for the reduction of the reproductive efficiency of cows affected by infections. However, since subclinical ketosis prevails in high production dairy herds, the objective of this literature review is to present the pathogenesis and the effects that this metabolic disorder has on the reproduction of dairy cows in the postpartum period, using indicators such as pregnancy rate, conception rate, return to cyclicity, calving interval and calving-estrus interval.(AU)

Asunto(s)

RESUMEN

Ketosis can seriously impair cow performance. This study detected changes in prepartum blood metabolic parameters for predicting postpartum ketosis occurrence in dairy cows. Body condition score (BCS) was assessed before and after delivery. Blood samples of 63 cows were collected from 10 days before calving to 10 days after calving to measure metabolic parameters including ß-hydroxybutyric acid (BHBA), non-esterified fatty acid (NEFA), glucose (GLU), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL), total protein (TP), albumin (ALB), globulin (GLO), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). There was a postpartum subclinical ketosis incidence of 42.25%. Compared with prepartum, plasma, levels of BHBA, AST, and NEFA significantly increased postpartum, and prepartum AST (R=0.57) and NEFA (R=0.45) showed a significant positive correlation with ketosis postpartum. Plasma GLU level significantly decreased postpartum and was significantly negatively correlated with ketosis (R=-0.21). Receiver operating characteristic curve analysis revealed prepartum BSC < 2.88, and prepartum plasma AST > 68.0 U/L, GLU < 3.97mmol/L, NEFA > 0.27mmol/L, and BHBA > 0.43mmol/L, indicating a high risk of subclinical ketosis postpartum. These levels can be used as risk indicators to predict the occurrence of subclinical ketosis in postpartum cows.(AU)

A cetose pode trazer sérios prejuízos ao desempenho da vaca. Este estudo detectou alterações nos parâmetros metabólicos do sangue pré-parto para prever a cetose pós-parto que ocorre em vacas leiteiras. O escore de condição corporal (ECC) foi avaliado antes e após o parto. Foram coletadas amostras de sangue de 63 vacas entre 10 dias antes e 10 dias após o parto para medir os parâmetros metabólicos, incluindo ácido ß-hidroxibutírico (BHBA), ácido graxo não esterificado (NEFA), glicose (GLU), bilirrubina total (TBIL), bilirrubina direta (DBIL), bilirrubina indireta (IBIL), proteína total (TP), albumina (ALB), globulina (GLO), alanina aminotransferase (ALT) e aspartato aminotransferase (AST). Houve uma incidência de cetose subclínica pós-parto de 42,25%. Em comparação com o pré-parto, o plasma, os níveis de BHBA, AST e NEFA aumentaram significativamente no pós-parto, e AST no pré-parto (R = 0,57) e NEFA (R = 0,45) mostraram uma correlação significativa positiva com cetose pós-parto. O nível plasmático de GLU diminuiu significativamente no pós-parto e foi negativamente correlacionado com a cetose de forma significativa (R = -0,21). A análise da curva característica de operação do receptor revelou BSC pré-parto <2,88 e AST plasmático pré-parto> 68,0 U / L, GLU <3,97mmol / L, NEFA> 0,27mmol / L e BHBA> 0,43mmol / L, indicando um alto risco de cetose subclínica pós-parto. Esses níveis podem ser usados ​​como indicadores de risco para prever a ocorrência de cetose subclínica em vacas no pós-parto.(AU)

Asunto(s)

RESUMEN

The aims of the present study were to investigate (1) the risk factors that influence the occurrence of clinical ketosis (CK; blood ß-hydroxybutyrate > 3.0 mmol/L) and (2) to determine the influence of subclinical ketosis (SCK; 1.2 ≤ ß-hydroxybutyrate ≤ 2.9 mmol/L) and CK on reproductive performance and milk yield in high-yielding Holstein cows in a hot environment. Cows (n = 345) were blood sampled from 6 to 15 days postpartum for ß-hydroxybutyrate (BHB) determination with a hand-held meter. Cows calving in spring had 3.7 increased odds of having CK (20.7% incidence) than cows calving in summer (3.9% incidence) and autumn (9.4% incidence). Temperature-humidity index < 83 was associated with 1.6 times higher risk for CK compared with cows calving in warmer days. First-service conception rate was 12 and 16 percentage point higher (P < 0.05) in nonketotic cows compared with cows with SCK and CK, respectively. Actual 305-day milk yields for healthy, SCK, and CK cows were 9991 ± 1411, 10,123 ± 1442, and 10,386 ± 1435 kg (mean ± SD), respectively, with no difference (P > 0.05) between groups. In conclusion, this study documented that ketosis was seasonal with lower incidence of this metabolic disease during hot seasons and with increased ambient temperature at calving. Also, 305-day milk yield of Holstein cows was not related to blood BHB content early in lactation in this hot environment. However, elevated circulating BHB was negatively associated with conception rate at first service and fetal losses.

Asunto(s)

RESUMEN

The purpose of this study was to estimate the prevalence of Subclinical ketosis (SCK) between 4 and 19 days in milk (DIM) in a grazing production system and investigate the importance of potential risk factors for SCK. This cross-sectional study was conducted in dairy cows (n = 107), which had more of two parities. The concentration of ß-hydroxybutyric (BHB) in blood was quantified through a hand-held meter. Potential risk factors evaluated were calving interval (CI), milk yield in previous lactation, metritis, dystocia, calf sex (male), parity (≤3 vs. ≥4) and pre-partum body condition score (BCS ≤ 3.5 vs. ≥3.75). Prevalence of SCK was 10.3% (95% CI 4.7-15) between 4 and 19 DIM. Risk factors identified were the occurrence of both metritis and pre-partum BCS ≥ 3.75. Cows with metritis had 4.9 (95% CI 1.17-20.98) times more risk of developing SCK than cows without metritis. And the cows with pre-partum BCS ≥ 3.75 had 5.25 (95% CI 1.32-21.11) times more risk of developing SCK than cows with pre-partum BCS ≤ 3.5. Metritis could induce a lower feed intake and promote the development of SCK. High pre-partum BCS could induce a greater mobilization of body reserves altering liver function and aggravating post-partum NEB. The results are indicative of the expected prevalence of SCK in grazing production system. Factors associated could help to identify cattle at risk of SCK and improve the management of strategies to limit the effects.

Asunto(s)