Document Type : Complete scientific research article
Authors
1
PhD, Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156–83111, Iran.
2
Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156–83111, Iran.
3
Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan 84156–83111, Iran
4
Department of Animal Science, Faculty of Agriculture and Natural Resources, Arak University, Arak, Iran.
Abstract
Background and objectives: In recent years, the issue of rearing suckling calves in cattle herds has been highly considered. Corn processing in the form of steam flaked (using high temperature and humidity) causes gelatinization of the semi-crystalline form of starch, which facilitates access to starch and thus improves starch digestion and rumen development. Also, the weaning protocol is a vital factor in the physiological and morphological development of the calf's rumen. Several studies have been conducted to identify the appropriate method of weaning. The results of past studies show that weaning method is affected by rumen development. Therefore, the aim of the present study was to investigate the interaction effect of corn grain processing method (steam flaked and finaly ground) with weaning method (gradual and abrupt) on blood metabolites, health and nutritional behavior of Holstein calves.
Materials and method: The present study conducted with using 48 Holstein calves with 38.2 ± 1.60 kg body weight (12 in each treatment, 6 males and 6 females) at the age of 3 days. The experimental design was a 2 × 2 factorial arrangement, resulting in four treatment groups: 1) steam-flaked corn and gradual weaning, 2) steamed flaked corn and abrupt weaning, 3) ground corn and gradual weaning, and 4) ground corn and abrupt weaning were allocated. Abrupt weaning was don on day 68 and 69 with daily reduction 3.5 liters of milk, while gradual according to reduction plan weaning was don between days 60 and 69. Weaning was performed on day 70 in all treatments and the experiment continued until day 90.In order to investigate the effect of experimental treatments on blood parameters, blood samples were taken from the calves on days 40, 60 and 80. Feeding behavior activities were recorded for three consecutive days on days 70 to 72. Also, health indicators were recorded on a daily basis.
Results: The results of the present study showed that the concentration of total protein (P=0.02) and albumin (P=0.04) in blood was higher in calves that were weaned abruptly than in calves that were weaned gradually. The interaction between corn processing type and weaning method for aspartate aminotransferase was significant (P=0.01), and calves receiving ground corn and weaned abruptly had higher concentrations of this enzyme compared to calves receiving steam-flaked corn and weaned abruptly. Calves receiving steam-flaked corn had lower respiratory scores (P=0.01) and general health status scores (P=0.01) than calves receiving ground corn. The interaction between corn grain processing method and weaning schedule on rectal temperature was significant (P=0.01), such that in calves receiving ground corn, abrupt weaning led to an increase in rectal temperature of calves.Except for feeding time (P=0.01), calf behavior was not affected by the experimental treatments. Gradual weaning of calves resulted in longer feeding time compared to abrupt weaning.
Conclusion: Based on the results obtained from this study, the use of steam-flaked corn decreased the level of blood urea nitrogen, which is probably due to the improvement of nitrogen utilization. Gradual weaning method decreased rectal temperature, albumin concentration, and also increased spent time for eating, which indicates stress reduction. In general, feeding the suckling calves with steam-flaked corn in combination with the gradual weaning method improved the performance of the suckling calves.
Keywords
Main Subjects
)