کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8501362 1553840 2018 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of repeated subacute ruminal acidosis challenges on the adaptation of the rumen bacterial community in Holstein bulls
ترجمه فارسی عنوان
اثرات چالش های اسیدوز رحم مکرر بر تطبیق باکتری های شکمی در گاوهای هلشتاین
کلمات کلیدی
جامعه باکتریایی، گاو چالش اسیدوز رامیکال زیر تکرار مکرر، شکمبه
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
چکیده انگلیسی
We investigated the effect of repeated subacute ruminal acidosis (SARA) challenges on the pH, fermentative function, and bacterial community in the rumen. Four rumen-cannulated Holstein bulls were fed a high-forage diet for 7 d (HF period) followed by a high-grain diet for 7 d (HG period). Four SARA challenges were carried out consecutively (first, second, third, and fourth challenges). The ruminal pH was measured continuously during the experiment, and rumen fluid samples during the first to fourth challenges were collected at 0800, 1400, and 2000 h on the last days of each feeding period for analysis; volatile fatty acid components, NH3-N, and lactic acid concentrations were measured. Bacterial community structure was analyzed at 0800 h during the first and fourth challenges on the last days of each period. The 24-h mean ruminal pH was decreased during the transition from high-forage to high-grain diet and tended to differ between the HF and HG periods. During the HG period, ruminal pH <5.6 was maintained for a longer period in the first and second challenges (350 and 405 min/d, respectively) than in the third and fourth challenges (both 120 min/d). A marked increase in total volatile fatty acid and NH3-N concentrations during the HG period was observed in the later challenges. In addition, lower and higher proportions of acetic and butyric acids, respectively, were observed during the HG period than during the HF period. A total of 37 core bacterial genera were found in all samples; however, the relative abundance of several genera differed significantly between the HF and HG periods (Prevotella, Ruminococcus, Eubacterium, and Oscillibacter) and between the first and fourth challenges (Eubacterium and unclassified Clostridiaceae). During the HG period, lower relative abundances of Prevotella, Eubacterium, and Oscillibacter and higher relative abundance of Ruminococcus were detected compared with during the HF period. The relative abundances of Eubacterium and unclassified Clostridiaceae were lower in the first challenge than in the fourth challenge. Bacterial diversity was greater during the HF period than during the HG period and was greater during the fourth challenge than during the first challenge. Interestingly, diversity indices during the HG period of the fourth challenge were higher than those during the HF period of the first challenge. These results suggested that rumen fermentation in Holstein cattle can adapt to repeated SARA challenges by minimizing the adverse changes in ruminal pH. Moreover, the composition and diversity of the ruminal bacterial community may be affected by ruminal pH and vice versa.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Dairy Science - Volume 101, Issue 5, May 2018, Pages 4424-4436
نویسندگان
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