Risk factors of calf diseases The epidemiological determinants or risk factors of diseases of calves under one month of age include:(1) Vigor and health of the calf at birth, (2) The level of colostral immunity achieved in the calf, (3) Management practices of the personnel caring for the calves , (4)Nutritional program including the quality of milk replacers. (5) Herd size, (6) Adequacy of the housing and environment, and (7)Season of the year. (I) Vigor and health of the calf at birth Several factors can affect the vigor and health of the calf immediately after birth and some of which are described below:
- If the nutritional status of the dams is adequate, nutritional deficiencies at birth are usually rare.
- Calves borne from dams affected with any disease associated with prolonged anorexia, fever or septicemia may be weak.
- Morbidity and mortality in calves arc associated with difficulty calving in first-calf heifers.
- Dystocia is affected by several nongenetic and genetic factors including age and parity of the dam, size of the calf, season of the year and degree of birth difficulty.
- The correlations between dystocia and calf mortality have been about 0.7.
- Small size cow has difficulty calving at early parities.