Comparison of Rumen Fluid pH by Continuous Telemetry System and Bench pH Meter in Sheep with Different Ranges of Ruminal pH

Abstract

We aimed to compare the measurements of sheep ruminal pH using a continuous telemetry system or a bench pH meter using sheep with different degrees of ruminal pH. Ruminal lactic acidosis was induced in nine adult crossbred Santa Ines sheep by the administration of 15 g of sucrose per kg/BW. Samples of rumen fluid were collected at the baseline, before the induction of acidosis (T 0) and at six, 12, 18, 24, 48, and 72 hours after the induction for pH measurement using a bench pH meter. During this 72-hour period, all animals had electrodes for the continuous measurement of pH. The results were compared using the Bland-Altman analysis of agreement, Pearson coefficients of correlation and determination, and paired analysis of variance with Student's t-test. The measurement methods presented a strong correlation (r = 0.94, P < 0.05) but the rumen pH that was measured continuously using a telemetry system resulted in lower values than the bench pH meter (overall mean of 5.38 and 5.48, resp., P = 0.0001). The telemetry system was able to detect smaller changes in rumen fluid pH and was more accurate in diagnosing both subacute ruminal lactic acidosis and acute ruminal lactic acidosis in sheep.

Avaliação hemogasométrica, bioquímica e hematológica de ovinos suplementados com melão

“…Os animais do G25% não manifestaram alterações sanguíneas evidentes após o súbito oferecimento de melão, que deve ter provocado acidose ruminal por ACC (subaguda) durante a 3ª a 6ª hora, como pode ser observado pelo valor do pH ruminal na Tabela 1. No G75%, todos os ovinos apresentaram alterações sanguíneas indicativas de acidose láctica ruminal aguda, com pH ruminal inferior a 5,0 a partir do T6 até o final do estudo (Reis et al, 2014).…”

“…Existem dois tipos de acidose ruminal. A primeira é de grau mais leve, causada por excesso de ácidos de cadeia curta (ACC), em especial pelo ácido propiônico, também denominada de acidose ruminal subaguda, cujo pH ruminal diminui abaixo dos valores considerados normais (5,9 -7,2), permanecendo o pH entre 5,6 a 5,1 quando nem sempre são constatados sintomas clínicos evidentes (Owens et al, 1998;Krause et al, 2006;Nagaraja e Titgemeyer, 2007;Reis et al, 2014).…”

Clinical evaluation of unadapted sheep submited to sudden intake of melon with high levels of sugar

“…Based on the pH of the ruminal fluid and according to the classification ruminal acidosis (REIS et al, 2014), it can be assumed that the G25% sheep had subacute ruminal acidosis for 6 hours after the melon offer, which was caused by excess chain fatty acids (SCFA). However, this change did not produce any obvious clinical symptoms in the sheep.…”

“…This disease results from an excessive intake of soluble carbohydrates, especially in nonadapted animals, and it may manifest as acute ruminal lactic acidosis (ARLA); subacute ruminal acidosis (SARA), or it may be chronic (BRAUN et al, 1992;LASKOSKI et al, 2014;LETTAT et al, 2010;REIS et al, 2014). Administering a concentrate to animals reduces the dietary fiber content, which decreases rumination and salivary buffering.…”

Characterization of Oligofructose-Induced Acute Rumen Lactic Acidosis and the Appearance of Laminitis in Zebu Cattle

“…Among the changes in rumen pH values, acute rumen acidosis (ARA) is caused by the abrupt consumption of a large amount of soluble carbohydrate, causing a sudden reduction in rumen pH to values below five, favoring the growth of gram-positive bacteria such as Streptococcus bovis, which produce lactic acid [4][5][6]. When the ruminal pH drops below 4.5, the Streptococcus bovis population dies, and the environment favors the population growth of Lactobacillus that produce more lactate [7][8][9].…”