BEHAVIOR OF HOLSTEINS, JERSEYS AND THEIR CROSSES ON PASTURE OF FORT HARE

Time spent on different activities by different genotypes may provide indicators which could result in improved management on pasture. For example, the knowledge of time spent on different activities may assist farmers to buffer the effects that may cause variation in feeding behaviour and total intake of the cows. One outcome could be that farmers can thereby partition resources by designing and implementing effective grazing management systems and by formulating economic supplementation programmes. With this knowledge they may adopt strategies like providing shade, shelter and high quantities and quality of feed to improve body condition, milk yield and welfare of the dairy cows. Having this in mind, the objective of the study of the researchers at Fort Hare (see reference below) was to determine the time spent on different activities related to feeding by Jersey and Holstein cows and their crosses in a pasture-based dairy system and how it affects milk yield.

The time budgets and daily milk yield of Jersey and Holstein cows and their crosses were compared by recording the time spent grazing, drinking, lying, standing and walking in four seasons of the year (cool–dry, hot–dry, hot–wet and post-rainy). Observations were made from 08:00 to 14:00 hours on seven cows per breed. Seven observers monitored the cows at 10-minute intervals for six hours using stop watches.

Time spent standing was higher for Holstein compared to Jersey cows and the crossbred cows during the hot–wet season. Time spent walking differed among the three genotypes with the Jersey spending more time in both the hot–wet and cool–dry seasons. No differences were noted on time spent lying down across the genotypes in the hot–wet season. In the cool–dry season, differences in time spent grazing were noted with the Jersey cows spending more time. The Holstein and the crossbred spent more time lying down than the Jersey cows in the cool–dry season. No time differences were noted for time spent standing in the same season. The Jersey cows spent the longest time walking during the cool–dry period. There were seasonal differences in time spent in all activities. Time spent on grazing was longest in the post-rainy season and lowest in the hot–wet season. Differences were also observed in the time spent lying down. The longest period was observed in the hot–dry season and lowest in the hot–wet season. Daily milk yield varied with breed with the Holstein and Jersey producing higher yields than the crosses. The highest amount was produced in the hot–dry and the least in the hot–wet season. Milk yield and lying down were positively correlated in both Jersey and Holstein cows whereas standing was negatively correlated with milk yield. 

It was concluded that the genotypes show different levels of sensitivity to seasons and that a relationship exists between milk yield and time budgets. Although the numbers of cows used in the study were inadequate to make definite recommendations, the study provides pointers to farmers about the importance of time budgets which they can measure on-farm to optimize feeding behaviour of the cows in different seasons. This could also suggest the provision of shades and shelter to improve milk yield.

Reference:

Madodana S. Dodzi & Voster Muchenje, 2012. Seasonal variation in time budgets and milk yield for Jersey,Friesland and crossbred cows raised in a pasture-based system. Trop Anim Health Prod.44:1395–1401