Rumen development in the calf

Abstract

I . Twenty-four Ayrshire bull calves were reared on either high-concentrate or high-roughage diets to study the effect of diet on the subsequent ability of the calf to digest either concentrates or hay when given alone. The rearing diets were known to produce different types of rumen development. 2. Although there were significant differences between the apparent digestibility coefficients of the high-concentrate and high-roughage rearing diets and between concentrates and hay when given alone, the subsequent ability of the calf to digest either concentrates or hay was unaffected by the type of diet given during the rearing period to 13 weeks of age. 3. The amount of nitrogen retained was significantly greater in calves reared on the highconcentrate diet than in those given the high-roughage diet, but similar amounts of N were retained/Ioo g gain in body-weight in both groups. After the change in diet, the amount of N retained was significantly greater in calves given concentrates after a rearing diet high in concentrates than in those given concentrates after a rearing diet high in roughage, although in both groups 32% of the N intake was retained. Four of the six calves given hay after a rearing diet high in concentrates were in negative N balance, but only one calf lost weight. Only 19% of the N intake was retained in calves given hay after being reared on a highroughage diet. 4. The concentration of total volatile fatty acids (VFA) in the rumen contents rose to reach peak levels at about 3 h after food was offered; the concentration then declined. VFA concentrations tended to be higher in calves given the rearing diet high in concentrates than in those given the one high in roughage, and differences reached significance when the diet was changed to one of all concentrates or all hay, with no obvious carry-over effect of the rearing diet. The proportion of propionic, butyric and higher acids tended to be greater in calves given high levels of concentrates than in those given high levels of hay and also tended to rise, irrespective of diet, as the concentration of total VFA rose. 5. A change of diet at 14 weeks from one high in concentrates to one consisting entirely of hay resulted in a significant decline in the viable counts of streptococci, lactobacilli and coliform organisms in the rumen liquor at 16 weeks. The numbers of bacteria were unaffected by the other dietary changes. 6. The concentration of total VFA in plasma of peripheral blood tended to be higher in calves given the high-roughage or all-hay diets. A fall in the concentration of plasma VFA occurred when calves were changed from a high-roughage diet to an all-concentrate diet and a rise in concentration was observed when an all-hay diet replaced one containing a high proportion of concentrates. 7. During the initial rearing period the mean blood plasma glucose concentration was 92.8 mg/Ioo ml in calves given the high-concentrate diet, a value significantly higher than the mean value of 64.5 mg/roo ml found in calves given the high-roughage diet....

Rumen Development, Intestinal Growth and Hepatic Metabolism In The Pre- and Postweaning Ruminant

“…A mixture of SCFA salts (propionate and butyrate included) fed as 10% (wt/wt) of a concentrate starter ration resulted in increased incidence of ruminal parakeratosis, and in all treated animals a thickening of the stratum corneum was reported in calves (Gilliland et al, 1962) and lambs (Rickard and Ternouth, 1965). Increasing amounts of concentrate in the diet resulted in no change in rumen muscularity but did result in increased papillae density and papillae height in calves (Stobo et al, 1966) and lambs (Rickard and Ternouth, 1965). None of these studies were able to definitively distinguish the mechanism responsible for the induction of papillary development.…”

Review: How Forage Feeding Early in Life Influences the Growth Rate, Ruminal Environment, and the Establishment of Feeding Behavior in Pre-Weaned Calves

“…These authors reported that as the concentrate intake increased, the hay intake decreased linearly [5,36], while live and empty body weight (BW) and rumen development were improved [36]. This is probably because concentrates result in more VFA production, especially propionate and butyrate [12], which enhances papillae development [13,36]. Collectively, these early studies suggested that in a high roughage feeding system, the addition of a bulky forage in the diet might decrease the consumption of energy-dense concentrates, leading to less rumen fermentation and lower degradation rates, and subsequently lower total nutrient intake and calf growth.…”

“…For example, cellulolytic microbes, such as Ruminococcus flavefaciens and Ruminococcus albus, are more prevalent in animals fed high forage diets, which increase fiber degradation and elevates the proportion of acetate in the rumen [42,52]. Both propionate and butyrate stimulate and enhance rumen epithelial development [12,13,99], with butyrate serving as the preferred energy source as well as modulating the gene expression in the rumen epithelium [96]. A low proportion of these two VFA may limit the growth of rumen papillae [42,52].…”

“…Concentrates, high in rapidly fermentable carbohydrates, produced more butyrate and propionate [12]. Therefore, higher proportions of concentrates could enhance the development of rumen papillae [13]. Furthermore, as fiber had lower digestibility than starch and sugar, many studies claimed that roughage increased gut fill because of low ruminal fermentation rate, thus curbing the consumption of starter feed which had higher energy density [5,14,15].…”

Effects of starch content of calf starter on growth and rumen pH in Holstein calves during the weaning transition

“…From our data, SARA does not appear to negatively affect feed intake and growth performance of calves during the weaning transition. It has previously been suggested that low rumen pH may be advantageous during rumen epithelial development (Stobo et al, 1966), as decreased luminal pH can depress epithelial intracellular pH in vitro (Müller et al, 2000). Modest acidification of intracellular pH to 7.0 prevented cellular apoptosis in kidney cells (Akimova et al, 2006), and activated mitogen-activated protein kinase signaling pathways, leading to cell proliferation (Sarosi et al, 2005).…”