Effect of season and roughage : concentrate ratio on weight gain of young buffalo

 

Dao Lan Nhi, Mai Van Sanh and Le Viet Ly

National Institute of Animal Husbandry, Hanoi

 

Abstract

Sixteen male buffaloes at 18 - 21 months of age with 170 - 190 kg liveweight were allocated to two treatments (roughage : concentrate ratio) in two seasons (wet and dry season) to investigate the effect on weight gains. For each treatment, 8 buffaloes were divided into 2 groups with similar age and body weight. The buffaloes were fed indoors with exercise daily. Each treatment was carried out for 90 days at the Centre for Livestock Research and Development in the mountainous region of Thai Nguyen province. The average daily gain was lower in the dry season (364 g/day) than in the wet season (620 g/day).  Feed conversion rates were 18.2 and 9.3 kg dry matter/kg gain for dry and wet seasons.   Liveweight gain was 364 g with 100% roughage  and 572 g with  70% roughage and 30% concentrate. Comparable data for feed conversion were 16.8 and 10.4 for the two diets, respectively. It is recommended that fattening of young buffalo should  be done in the wet season to increase quantity and quality of meat.

Keywords: Buffaloes, season, fattening, concentrate: roughage 

Introduction

The swamp buffalo is a dual purpose animal which can give good quality meat. In 1998, the population of buffalo was 2.95 million in the whole country and supplied 35% of total beef in the market.  The buffalo can consume a large amount of roughage which is usually of low nutritional value.  In the mountainous area, the roughage sources such as natural grass, rice straw are available around the year but are not yet used fully for buffalo production.

 

The aim of this experiment was to study the effects of season and roughage:concentrate ratio on weight gain of fattening young buffalo from 18 - 21 months of age.

 

Materials and methods

Location

The experiments were carried out at the Centre for Livestock Research and Development in the mountainous region of Thai Nguyen province, where the average temperature is 22 ºC and the average humidity 80 - 88%.

 

Treatments

The experiment was carried out on 16 male buffaloes (18 - 21 months of age with liveweight of 170 - 190 kg) allocated to two roughage: concentrate ratios (R100 and R70) in two seasons: rainy and dry season.  In each treatment, 8 buffaloes were divided into 2 groups with similar age and body weight. They were fed indoors with exercise daily for a few hours.

 

Feeding system

Roughages were ad libitum urea-treated (4%) rice straw in the dry season with 6 kg/day natural grasses and in the wet season natural grasses ad libitum (Table 1). The concentrate was fresh cassava roots and rice bran.  The buffaloes were weighed monthly on 2 consecutive days, before feeding and drinking, for determining the liveweight. The buffaloes in treatment  R00 were slaughtered at the end of the rainy season.

 

Measurements

Samples of feeds were analysed for proximate constitutents  (AOAC 1990). Data were analyzed by the ANOVA program in the Minitab software (version 11). The feeding periods were for 90 days (excluding the adaptation time of 10 days for getting accustomed to  the experimental diets).

   
Results and discussion

Feed  intake

There were no differences in dry mater intake  between the dietary treatments (Table 2). This is similar to the findings of  Wanapat and Wachirapakorn (1990) when they fattened buffaloes at the same age with rice straw and concentrate within 9 months.

 

 

 

The crude protein content of the diet in the dry season was lower than in the rainy season, and less than the level considered to be necessary for adequate rumen function (Preston and Leng 1987). In the rainy season, the buffaloes consumed 20 - 26 kg natural green grass per day which provided more crude protein than the urea-treated straw and restricted grass given in the dry season.

 

Weight gain

The buffaloes grew faster in the wet than in the dry seasons and on the diet with the higher ratio of concentrates (Table 3).  Feed conversion was  related to the rate of weight gain and favoured the wet over the dry season and the higher ratio of concentrates. These responses can be explained by the effects of the treatments on the nutritive value of the diet (Table 2).

 

 

Meat percentage and quality

The data on two of the buffaloes slaughtered from each of the dietary treatments (Table 5) for the wet season study indicated that the carcass yield was not affected by diet, but that yiled oif lean meat and fat was higher on the diet with the higher level of concentrates.

 

 

The carcass yields are lower than those reported by Wanapat (1990) and  Dahlan (1996), which were 48.3 and 50.0%, respectively for swamp buffalo and by Han Zhengkang (1990) for crossbred buffaloes (56.1%). 

 

Conclusions

• Season affected fattening performance of buffaloes because of the ready availability of grass in the wet season whereas urea-treated rice straw had to be used in the dry season with only a limited (6 kg) supply of grass.  Growth rates were 360 and 570 g/day in the wet and dry seasons.
• Replacing 30% of the roughage with 6 kg fresh cassava roots and 0.5 kg rice bran increased growth rate from 360 top 570 g/day.
• Feed conversions were 16.9 and 10.4 kg dry matter per 1 kg liveweight gain for the diets with and without concentrates.

 

References