Processing ruminal ingesta to release bacteria attached to feed particles

Abstract

A comparison was made of different methods of processing ingesta to release bacteria attached to solid particles, prior to making viable counts. Initially processing was performed under a stream of anaerobic gas and counts were made using the roll tube technique. Later, processing was done in an anaerobic cabinet and counts were made using the plating technique. On long hay diets counts of total culturable and lactateutilizing bacteria were twice as high with the Stomacher and Ultra-Turraxt reatment of ingesta when compared with the Minimal treatment. On the chopped hay and high concentrate diets there was little difference between the processing methods in respect of counts of these two groups of bacteria. Counts of cellulolytic bacteria which are attached to ingesta particles were higher with the Minimal treatment than with the other two methods. In contrast, counts of the ciliate protozoa showed a marked difference owing to processing. Results from the later experiments done in the anaerobic cabinet showed that poor anaerobiosis was responsible for at least some of the lethal action of the Ultra-Turraxa ndStomacher. 

'n Vergelykendes tudie is gedoenv an die verskillende behandelingsv an verteringsmateriaaol m baterie€ wat vassit aan die vaste deeltjies te bevry voordat lewensvatbare tellings gedoenw ord. Oorspronkliki s die behandelingo nder'n stroom ana6robe gas gedoen en tellings is in rolbuise gedoen. Later is die behandelingsi n 'n ana6robek abinetg edoene n die tellings is volgens die plaattegniek gedoen. Op rantsoene van lang hooi was die tellings van die totale telbare en die melksuur-benuttendeb aterie6 twee maal so hoog vir die 'Stomacher'e n die 'Ultra-Turraxb' ehandelinga, s vir die Minimum behandelingO. p die gemaaldeh ooi en ho€ konsentraat rantsoene was daar baie min verskil tussen die behandelingst en opsigtev an tellings van die twee groepe bakterie€.T ellingsv an die sellulolitieseb akterie€w at vassit aan die deel t j iesw as ho€rv i r die Minimumb ehandel inga s vi r die ander twee metodes. In teenstelling hiermee, het die tellings van die siliaat protoso€ merkbare verskille getoon ten opsigte van die behandelings. Resultatev an lateree ksperimentew at in die ana6robe kabinet gedoen is, het getoon dat swak ana6robiose verantwoordelik was vir ten minste sommige van die nadelige uitwerkingv an die 'Ultra-Turraxe' n die 'Stomacher'.

Keywords: Ruminal bacteria, ciliate protozoa, processing ruminal ingesta, viable counts