اثر جایگزینی سطوح مختلف سبوس برنج روغن کشی شده با کنجاله سویا بر تولید و ترکیبات شیر، نمره وضعیت بدنی و برخی فراسنجه های خونی گاوهای شیری

به منظور تعیین اثرات جایگزینی سطوح مختلف سبوس برنج روغن کشی شده با کنجاله سویا، بر تولید و ترکیبات شیر، الگوی اسیدهای چرب شیر، نمره وضعیت بدنی و برخی فراسنجه های خونی گاوهای شیری، آزمایشی با استفاده از تعداد 12 راس گاو شیرده نژاد سیمنتال دو شکم زایش، با میانگین وزن ابتدای دوره27±630 کیلوگرم، میانگین تولید شیر 1.7 ±35 لیتر در روز و میانگین روزهای شیردهی17± 109روز در قالب طرح کاملاً تصادفی با چهار تیمار و سه تکرار انجام شد. تیمارهای آزمایشی شامل جیره شاهد فاقد سبوس برنج روغن کشی شده و جیره های حاوی سبوس روغن کشی شده جایگزین 50، 75 و 95 درصد از کنجاله سویا بود. نتایج آزمایش نشان داد که جیره های آزمایشی در مجموع اثر معنی داری بر ترکیب و تولید شیر داشتند، طوری که تولید شیر در تیمار حاوی سبوس برنج روغن کشی شده جایگزین شده با 75 درصد از کنجاله سویا، بیش از سایر تیمارهای آزمایشی بود. نمره وضعیت بدنی به طور معنی داری تحت تاثیر جیره های آزمایشی قرار نگرفت. اثر تیمارها روی الگوی اسیدهای چرب شیر معنی دار نبود. همچنین افزودن سبوس روغن کشی شده برنج، تاثیر معنی داری روی فراسنجه های خون داشت، طوری که با افزایش سطح سبوس برنج در جیره تا 75 درصد جایگزین کنجاله سویا، سبب کاهش معنی داری مقادیر فراسنجه های خونی به جز گلوکز شد. با توجه به نتایج حاصل از این آزمایش، سبوس برنج روغن کشی شده جایگزین 75 درصد از کنجاله سویا در جیره نسبت به تیمار شاهد باعث افزایش تولید شیر و کاهش درصد چربی در گاوهای شیری شد.

The Effect of Different Levels of Deoiled Rice Bran Replacement to Soybean Meal on Milk Production and Composition, Body Condition Score and Some Blood Parameters in Dairy Cows

Introduction:;The use of agricultural products that are often less costly has long been considered by researchers, and due to some problems with the direct use of these products in animal nutrition, their processing seems to be necessary in a variety of ways. In the meantime, byproducts derived from cereals, such as wheat bran and rice bran, are especially important due to their high production and low prices. Rice bran can be one of the world 's largest cereal processing byproducts. Considering the significant amount of rice bran production in the northern provinces of Iran, its low price and the possibility of replacing it as part of the ration and, on the other hand, due to the presence of unsaturated oil, it seems that its lubrication It will probably increase the maintenance time and improve its nutritional value. The main problem is the use of rice bran, phosphate phytate, oil and high silica. Considering the significant amount of rice bran production in the northern provinces of the country, its low price and the possibility of replacing it as part of the ration and, on the other hand, due to the presence of unsaturated oil, it seems that its lubrication It will probably increase the maintenance time and improve its nutritional value. The objective of this study was to evaluate the different levels of deoiled rice bran replacement to soybean meal on milk production and composition, the profile of fatty acids in milk, body condition score and some blood parameters of dairy cows.;Material and methods:;An experiment was conducted using 12 of Simmental dairy cows with a mean weight of 630±27 kg, a mean milk yield of 35±1.7 liters per day and an average of 109±17 days of lactation in a completely randomized design with four treatments and three repetitions. The experimental treatments were included control diets without deoiled rice bran and diets containing deoiled rice bran replacing 50, 75 and 90% to soybean meal. The diet used was based on the table of nutrient requirements of NRC, (2001) and the diet was prepared by the NRC, (2001) software. The traits studied in this experiment included milk composition and production, body condition score, profile of milk fatty acids and some blood serum parameters of dairy cows. The oilrice bran used in this experiment was prepared from Mazand factory, located in Mazandaran province, Babolsar city. The data were collected and experimental design was a completely randomized design with four treatments and three replicates using 12 heads of dairy cows with repeat measurement and using the GLM and SAS software (9.1).;Results and discussion:; The experimental results showed that the experimental diets had a significant effect on the composition and production of milk, so that the production of milk in a treatment containing deoiled rice bran replaced with 75% soy meal was more than other experimental treatments. The percentage of milk protein in a treatment containing deoiled rice bran replaced with 50% soy meal was more than other experimental treatments. Also, the results showed that the highest percentage of milk fat in the control treatment and the lowest milk fat in the treatment of deoiled rice bran was replaced with 75% soybean meal, which had a significant difference with other treatments. There was no significant difference in the number of somatic cells between treatments. Body condition scores were no significantly affected by experimental diets. The effect of treatments on milk fatty acids was not significant. Also, the addition of deoiled rice bran had a significant effect on blood parameters, so that by increasing the level of rice bran in the diet, up to 75% of the soybean meal replaces a significant decrease in blood levels other than glucose. In addition, the control treatment had the highest levels of triglyceride and cholesterol and the amount of HDL in treatment containing deoiled rice bran replaced with 75% soy meal was significantly higher than other treatments.;Conclusion:;According to the results of this experiment, the use of 75% of deoiled rice bran replacement to soybean meal in the diet, increased milk yield and reduced fat percentage in dairy cow compared to control treatment. Also, the reduction of cholesterol, triglycerides and HDL levels in dairy cows were observed treatment containing deoiled rice bran replaced with 75% soy meal. It seems that the use of 75% of deoiled rice bran replacement to soybean meal in the diet, showed better performance than the other levels in the production factors of dairy cows in this study.