"Experientia docet" - Experience is the best teacher
Voluntary intake of hay and silage: The role of intake related rumen characteristics
Experiments were conducted to examine the difference in intake between hay and silage made from lucerne (Medicago sativa) and whether these differences could be accounted for in terms of physical rumen characteristics. Voluntary intake was lowest on lucerne hay ensiled…
Influence of roughages on rumen retention time of concentrates
The effect of roughages on the retention time of concentrates in the rumen was studied in cattle and sheep fed diets with different concentrate:roughage ratios. The organic matter retention times were calculated from the ratio, OM content in the rumen/mean…
An enzymatic approach to cell wall structure
Ruminococcus albus was incubated with isolated alfalfa cell wall material for 72 h in batch culture. Cellulose in the cell walls was digested to a somewhat greater extent (88%) than were the fermentable sugars of the hemicellulose fraction (62 -…
Processing ruminal ingesta to release bacteria attached to feed particles
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…
Media lacking rumen fluid for enumeration of rumen bacteria
A medium without rumen fluid but containing trypticase, hemin and volatile fatty acids was developed for the enumeration of rumen bacteria. Counts of total culturable and amylolytic bacteria were as high or higher than those obtained using medium CC (Zeigler-Leedle…
Nutritionally fastidious Ruminococcus flavefaciens strains
The majority of Ruminococcus flavefaciens strains isolated in our laboratories failed to grow or grew poorly both in rumen fluid medium and in a chemically defined medium containing all the nutrients reported to be required for good growth of this…
Bacterial flora, protozoal fauna and volatile fatty acids in the rumen of the water buffalo (Bubalus bubalis) in tropical Asia
The composition of the ruminal flora and the VFA concentration were surveyed in the water buffalo found in tropical Asia. The results showed that the average concentration of VFA in rumen contents was 57 mM and the number of bacteria…
Distribution of urease producing bacteria in the rabbit caecum
The distribution of urease-producing bacteria was examined in lumenal and mucosal-associated populations of the rabbit caecum. The total number of bacteria recovered on a nonspecific, semi-defined medium were 1,7 x 109 per g from lumen contents and 2,0 x 105…
Rumen fungal degradation of Digitaria pentzii
The intake of Digitaria pentzii grown with sulphur fertilizer (0,14%; + S) was almost 50% higher than that of unfertilized forage (0,08%; - S). Results showed no differences in plant anatomy or in rumen bacterial populations in sheep fed +…
Colorimetric determination of in vitro feed protein degradation
A colorimetric method for determining protein degradation using a diazonium chromophore was compared with the Dacron bag technique. Diazotized fish meal, maize gluten meal and soya-bean were incubated with strained rumen fluid and a suitable growth medium. Only 49% and…
Estimation of protein degradation in rumen by three methods
The rumen degradability of protein in diets containing maize straw, fish meal and 0, 30 and 60% maize grain was estimated in three ways: (i) from the difference between the total non-ammonia N and microbial N entering the duodenum over…
Adaptation effects of ionophores on rumen fermentation
The effect of monensin on the in vitro degradation of cellulose was investigated using ruminal fluid obtained from sheep adapted and unadapted to the antibiotic. In vivo ruminal adaptation to monensin was also examined over a six-week treatment period. Results…
Effect of diet and physiological state on recycling of urea in Merino ewes
The recycling of urea to the rumen was studied in Merino ewes during different physiological states using radioactive tracers. The results showed that although the proportion of urea recycled differed, similar amounts were recycled in dry and pregnant sheep over…
A comparison of lipolysis and lipogenesis in sheep and rats
Hormone sensitive lipase is thought to be the rate-limiting enzyme of lipolysis; phosphatidate phosphohydrolase that of lipogenesis. Both these enzyme systems were studied in vitro with the addition of epinephrine. The results show that: (a) hormone sensitive lipase is four…
Homeorhetic hormones, metabolites and accelerated growth
Six newly weaned karakul ewes, three with fat tails and three without tails, were used to investigate the metabolic and hormonal changes during accelerated growth. Two lambs acted as controls, while the remaining four were Subjected to a maintenance diet…
Integration of metabolism and digestion in the hyrax
Metabolic adaptations and digestive ability were integrated to explain the ecological efficiency of the hyrax (Procavia capensis). Metabolic rate was shown to decrease linearly with a drop in ambient temperature, but at a lower rate than an animal of equivalent…
