Comparison of Techniques for Measurement of Rumen pH in Lactating Dairy Cows

Abstract

Subacute rumen acidosis is thought to be a common condition in early lactating dairy cattle; however, diagnosis is difficult. There are currently only two techniques available for measuring rumen pH under field conditions: rumenocentesis and oral stomach tube. Sixteen rumen-fistulated cows were sampled in four sites of the rumen (cranial-ventral, caudal-ventral, central, and cranial-dorsal) with a rumen cannula. Rumen pH results were compared to those obtained at the same time with rumenocentesis and with an oro-ruminal (Geishauser) probe. Rumen fluid was obtained between 6 and 12 wk of lactation. Samples were analyzed for pH, lactate, bicarbonate, sodium, potassium, and chloride. Rumen pH results were also compared to those obtained from 24-h continuous rumen pH measurement using indwelling rumen pH probes. Oro-ruminal probe samples had the highest pH values and the highest bicarbonate concentrations. Rumenocentesis samples had the lowest pH values and the lowest bicarbonate concentrations. Small differences in electrolyte concentrations were noted among rumen fluid collection techniques in the different rumen sites. The highest correlations of rumen pH were obtained between rumenocentesis and rumen cannulation (cranial-ventral), and between rumen cannulation (cranial-ventral) and the 24-h indwelling pH meter. Compared with samples obtained from the cranial-ventral rumen, rumenocentesis was more sensitive than the oro-ruminal probe in the measurement of low rumen pH; both techniques were moderately specific. The most accurate field technique was rumenocentesis. Improved field techniques are required for better on-farm diagnosis of subacute rumen acidosis.

Design, implementation and interpretation of in vitro batch culture experiments to assess enteric methane mitigation in ruminants—a review

“…Access to surgically-modified animals is not universal, and therefore less invasive techniques, such as oral stomach probing, have been used as an alternative. In the relatively few studies that have compared sampling through the rumen cannula or by stomach probing, differences in fermentation profile and microbiota have been reported in some (e.g., Geishauser and Gitzel, 1996;Duffield et al, 2004) but not all cases (e.g., Lodge-Ivey et al, 2009;Shen et al, 2012;Terré et al, 2013). Part of the discrepancy between studies may reflect differences in the procedures used to avoid salivary dilution and contamination, the type of samples collected and rumen sampling site.…”

Ruminal pH and temperature, papilla characteristics, and animal performance of fattening calves fed concentrate or maize silage-based diets

“…The pH values tend to peak in the moments before feed intake, begin to fall afterward, and reach the minimum between 3 and 6 h after feed intake depending on the ration (Duffield et al, 2004;Marden et al, 2005;Palmonari et al, 2010). As acid production decreases, volatile fatty acid absorption and rumen buffer capacity (mainly from saliva) increase, and pH begins to recover initial values; this process is estimated to last approximately 18 h (Whitelaw et al, 1970;Maekawa et al, 2002;Palmonari et al, 2010).…”

Subacute ruminai acidosis in dairy cows

“…Για τη μέτρηση του pH του στομαχικού περιεχο μένου των αγελάδων περιγράφονται δύο μέθοδοι στη διεθνή βιβλιογραφία: 1) Στιγμιαία μέτρηση, μετά από λήψη περιεχομένου με στομαχικό καθετήρα ή, προ τιμότερα, με παρακέντηση της μεγάλης κοιλίας και μέτρηση του pH με κατάλληλη συσκευή και 2) συνεχής (μακροχρόνια) μέτρηση, με τοποθέτηση ειδικής συσκευής-πομπού στη μεγάλη κοιλία (μετά από χει ρουργική επέμβαση και δημιουργία μόνιμου συριγ γίου) που αποστέλλει τις μετρήσεις του ρΗτου περιε χομένου της σε ειδικό δέκτη, συνδεδεμένο με ηλε κτρονικό υπολογιστή, καταγράφοντας έτσι τις τιμές του pH ολόκληρο το 24ωρο (Duffield et al 2004). Η τελευταία μέθοδος βρίσκει εφαρμογή για ερευνητι κούς σκοπούς και όχι στην κλινική πράξη.…”