Structural growth, feed consumption, rumen development, metabolic response, and immune response were studied in Holstein calves fed milk through either a conventional method or a step-down (STEP) method. In the conventional method, calves (n = 20) were fed colostrum and then milk at a rate of 10% of their BW for the entire period of 44 d. In the STEP method, calves (n = 20) were given colostrum and then milk at a rate of 20% of their BW for 23 d, which was reduced (between d 24 to 28) to 10% of their BW for the remaining 16 d. The calves on both methods were weaned gradually by diluting milk with water between d 45 and 49. After weaning, feed consumption, structural growth, and body weight gain were monitored until calves were 63 d of age. At d 63, twelve calves (6/treatment) were euthanized and rumen papillae length, papillae width, rumen wall thickness, and emptied forestomach weight were recorded. At wk 4, 7, and 9, ruminal contents were collected to enumerate rumen metabolites. The STEP-fed calves consumed a greater amount of milk than conventionally fed calves during the pre-STEP (d 1 to 28), post-STEP (d 29 to 49), and preweaning (d 1 to 49) periods. Consumption of starter and hay was greater during the pre-STEP period and lesser during the post-STEP and postweaning (d 50 to 63) periods in calves on the conventional method than on the STEP method. Body weight gain and structural growth measurements of calves were greater on the STEP method than on the conventional method. A hypophagic condition caused by greater milk consumption depressed solid feed intake of STEP-fed calves during the pre-STEP period, and a hyperphagic response caused by a reduced nutrient supply from milk triggered their consumption of solid feed during the post-STEP and postweaning periods. Ruminal pH and concentrations of ammonia, total volatile fatty acids, acetate, propionate, butyrate, and plasma beta-hydroxybutyrate were higher in calves on the STEP method and at weaning and postweaning (d 63) were lower in calves on the conventional method. Emptied weight of the forestomach, rumen wall thickness, papillae length, papillae width, and papillae concentration were higher in calves on the STEP method than in those on the conventional method. Blood glucose was lower, and blood urea nitrogen and beta-hydroxybutyrate at weaning and postweaning were higher in STEP-fed calves. Serum IgG, IgA, and triglycerides for 1, 2, and 3 wk of age were higher in calves on the STEP method than in those on the conventional method. In conclusion, greater feed consumption, BW gain, and structural growth, and a more metabolically and physically developed rumen were observed in calves on the STEP method than in those on the conventional method.
The objective of this study was to investigate the calf death and analyse the causes of the mortality by based on medical records and autopsy findings during 10 years in a large dairy farm. Total of 1,361 calf born and 146 calf dead during the invested period. Mortality rate was 10.7% and showed the big difference by year-specific mortality from 2.8% (4 calves) to 19.2% (28 calves). The highest rate of mortality was 1 week age (18.5%, 27 calves) and followed by 2 week age (11.6%, 17 calves) and mortality of more old calf tended to be reduced. The death less than 4 weeks and 8 weeks of age of the entire mortality accounted for 41.1% (60/146 calves) and 70.0% (102/146 calves), respectively. Causes of calf death were digestive diseases (53.4%), respiratory diseases (17.1%), musculoskeletal disease (8.2%), and systemic disease (8.2%) in order. Specific causes of calf death was highest in enteritis (43.2%), followed by pneumonia (14.4%), sepsis (8.2%) and fractures (3.4%). Seasonally, most of calf death happened in winter (48.6%) and then fall (21.2%). This results showed that enteritis and pneumonia are the main reason of calf death but other reasons were involved in calf death on the based on autopsy finding. On going research relating factors of calf mortality is needed.
OBJECTIVE This study aimed to find the radiographic characteristics for the detection of hypertrophic cardiomyopathy (HCM) and congestive heart failure (CHF) in cats. ANIMALS Healthy cats (n = 35) and HCM cats with (21) and without (22) CHF. METHODS On radiography, the cardiac size using vertebral heart score, left atrium enlargement (LAE), and dilation of the pulmonary vessels were assessed. The sensitivity and specificity of the radiographic characteristics regarding LAE were evaluated with the echocardiographic left atrium to aortic root ratio as a reference. RESULTS In HCM cats, cardiomegaly, LAE, and dilation of the caudal pulmonary artery were found compared with those in healthy cats. The LAE could be predicted using the elevation of the carina with 94.12% specificity but 17.5% sensitivity. When CHF developed, LAE and dilation of the caudal pulmonary vein (PV) were significantly different compared with those in HCM cats without CHF. The distal side of the summated shadow made by the right caudal PV with the ninth rib in HCM cats with CHF was significantly larger than that in HCM cats without CHF and a cut-off value of 5.35 mm was drawn with 75% sensitivity and 100% specificity. CLINICAL RELEVANCE Although there was an overlapping of radiographic findings between healthy and HCM cats, radiographic assessment of LAE can be useful for predicting HCM and the distal side of the summated shadow made by the right caudal PV with the ninth rib can predict CHF in HCM cats.
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