نوع مقاله : مقاله پژوهشی
1 دانش آموخته، گروه علوم دامی، دانشکده کشاورزی، دانشگاه فردوسی مشهد
2 عضو هیئت علمی- دانشکده کشاورزی دانشگاه فردوسی مشهد
3 استاد، گروه علوم دامی ، دانشکده کشاورزی، دانشگاه فردوسی مشهد
عنوان مقاله [English]
Background and objective: In order to increase efficiency and productivity, the need to use high-energy concentrate in dairy cows rations seems to be essential. This type of feed increases the risk of subacute ruminal acidosis, which leads to reduced dry matter intake, milk production and fat content. Therefore, different types of buffers are used to reduce the above consequences. Most buffers used in livestock farms include sodium carbonate, potassium bicarbonate, potassium carbonate, potassium bicarbonate, magnesium oxide, magnesium carbonate and bentonite. Scientific reports on ration containing buffers has a significant effect of fermentation parameters such as volume of gas production, potential and consistent rate of gas production.
Materials and Methods: In this study, three types of rations for dairy cows compose 50:50, 40:60 and 30:70 forage to concentrate rations and 4 types of buffers and alkalizer including sodium bicarbonate, sodium carbonate, potassium carbonate and magnesium carbonate were examined by in vitro technique. The squence of this experiment included determining the initial pH, buffering capacity and buffering value index, determining the effect of buffers on the rate of fermentation parameters, microbial production and utilizable crude protein at the duodenum of different diets in terms of forage to concentrate ratios.
Results: The results of this experiment showed that the highest acidogenicity value was related to the treatment of low forage rations containing sodium bicarbonate buffer, which was significantly di
fferent from the control treatment. The rate of microbial protein production, in gas technique,indicated that highest amount of microbial protein was produced in the low-forage ration containing sodium bicarbonate buffer. In the microbial protein production experiment, it could be used in the small intestine. The highest amount of protein that could be used in the small intestine at eight and Twenty-four hours was related to the treatment of low forage feed containing sodium bicarbonate buffer.
Conclusion: The results of treatments indicated that the buffering capacity of sodium carbonate, potassium carbonate and magnesium carbonate was significantly higher than sodium bicarbonate. The use of sodium bicarbonate and potassium carbonate buffers in low forage diets increases gas production and increases microbial protein. The amount of utilizable crude protein at the duodenum was the highest when using sodium bicarbonate and potassium carbonate buffers. It seem by usingthe componds with higher buffering capacity, the fate of ruminal nitrogen alter via increasing of microbial protein production and utilizable crude protein at the duodenum. It is better to use the mixture of these buffers based on the buffering capacity on in vivo.