The goal of this study was to examine the development of the reticulum, rumen, omasum and abomasum in six calves from birth to 100 days of age by means of six serial ultrasonographic examinations. The examinations were carried out in standing animals using a 5 MHz-transducer as described previously. The calves were primarily fed milk until examination 4 and then they were weaned. The reticulum ...

The objective of the study was to measure net AA flux rates across the portal-drained viscera (PDV) and liver in the presence and absence of abomasal glucose infusion. Decreasing the fraction of AA metabolized by the mucosal cells may increase the fraction of AA being released into the blood. A potential mechanism to reduce AA catabolism by mucosal cells is to provide an alternative source of e...

1. Three experiments were conducted to determine the flow of nitrogen through the rumen and abomasum when cows, steers and lambs were totally nourished on volatile fatty acids infused into the rumen. 2. In two dairy cows (650-700 kg) and two large steers (370-405 kg) the daily flow of non-ammonia-N (NAN) from the rumen was 50.7 and 58 mg/kg live weight (W)0.75 respectively. 3. The flows of NAN ...

Subacute ruminal acidosis can result in increased flow of fermentable substrates to the hindgut, which can negatively affect animal health and productivity. However, animal responses to increased hindgut fermentation independent of subacute ruminal acidosis have rarely been evaluated. This study determined the impact of abomasal dosage of a fermentable carbohydrate on animal performance and blo...

Management of gastrointestinal parasites is a critical issue for sheep producers worldwide. Increases in the prevalence of drug-resistant worms have complicated parasite control and increased economic losses. Therefore, other methods of parasite control need to be assessed, including the use of genetically resistant animals in breeding programs. Hair sheep breeds such as the St. Croix have grea...

Two studies were conducted to evaluate the effects of abomasal carbohydrate infusion on nutrient digestibility and fecal measures. In Exp. 1, 5 Holstein steers were assigned to a Latin square with 1-wk periods and were abomasally infused on a single day at the end of each period with water alone, a single pulse dose of water with 1 g/kg BW oligofructose or cornstarch, or 4 pulse doses of water ...

Holstein steers were used in two 5 x 5 Latin square experiments to evaluate the sparing of methionine by alternative sources of methyl groups (betaine and choline). Steers were housed in metabolism crates and limit-fed a soybean hull-based diet high in rumen degradable protein. To increase energy supply, ruminal infusions of volatile fatty acids and abomasal infusions of glucose were provided. ...

I . Two experiments were carried out with sheep and cattle receiving high-concentrate rations to estimate the amount of digestion taking place in the rumino-reticulum and omasum. Two techniques were used for the collection of samples of abomasal contents. In the experiment with sheep, animals were slaughtered at different times after feeding and samples of digesta were collected. In the experim...

The objective of this experiment was to assess ruminal outflow and apparent total-tract digestibility using digesta samples from 3 sites (reticulum, omasum, and abomasum) and 3 marker methods (single marker: indigestible NDF [iNDF; sample without separation]; double marker: iNDF + Co-EDTA [filtered sample]; and triple marker: iNDF + ytterbium [Yb] acetate + Co-EDTA [filtered and centrifuged]) i...

Sternbauer, K. 2005. Metabolic studies in cattle using the hyperinsulinemic euglycemic clamp technique. Doctoral dissertation. ISSN 1652-6880, ISBN 91-576-7037-4. Hyperinsulinemic euglycemic clamp, HEC, originally developed for determing insulinmediated glucose disposal and insulin sensitivity in humans, was used and evaluated in cattle. In the present study the following investigations were pe...