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9. Energy requirements of cattle for standing and for ingestion, estimated by a ruminal emptying technique

Author

Susenbeth, A., Dickel, T., Sudekum, K.-H., Drochner, W., and Steingass, H.

Subjects
Animal feeding and feeds, Cattle, Zoology and wildlife conservation
Abstract

Energy requirements for ingestion and standing were determined in open-circuit respiration chambers with four ruminally cannulated German Red Pied steers weighing 617 [+ or -] 53 kg of BW (mean [+ or -] SD). The requirement for standing over lying was derived by regressing heat production on time spent standing within 2-h periods when no feed was offered to avoid any interference with eating activity, and amounted to 14 kJ/(d*kg of BW). The energy requirement for ingestion was determined by calculating the difference between heat production during a 2-h period without feed and during a consecutive 2-h period in which straw of different particle sizes, fresh and conserved grass, or rolled barley were offered for ad libitum intake. Before measurements, the rumens of the steers were emptied, washed, and filled with a buffer solution to avoid heat production by metabolism of absorbed nutrients from the feed ingested during the experimental periods. The mean value for all feeds tested was 20 J/(min of ingestion * kg BW). Relating heat production to the amount of DM or fiber ingested did not decrease variation among feeds. This confirms the observations of earlier studies, that energy requirement for ingestion is mainly determined by time spent eating. Results of additional measurements, in which the same amounts of the respective feeds ingested in preceding periods were put into the emptied rumens via the cannulas, showed that the presence of the feed in the rumen did not increase heat production, indicating that the increment of heat production during eating is mainly caused by ingesting and chewing the feed. Further measurements in the same animals with an ingesta-filled rumen showed that ingestion of straw led to an increase in heat production per minute of chewing similar to those with emptied rumens, which confirms the validity of the experimental procedure using ruminally emptied animals to determine the energy requirement for ingestion. Key Words: Cattle, Energy Cost of Activities, Energy Requirements, Ingestion, Rumen

Published
2004

25. Effect Of Feeding Hordeum jabatum Hay Supplemented With Leucaena leucocephala On Nutrient Digestibility In Sheep

Author

Osakwe, I I and Drochner, W

Abstract

The fermentation profiles and nutrient digestibility of Leucaena leucocephala as a supplement to Hordeum jabatum hay was investigated using twelve castrated sheep averaging 24.4 ± 2.2 kg body weight (BW). Six of the sheep were fistulated at the rumen and used for ruminal pH, ammonia and volatile fatty acid determination in rumen fluid. Dried leaves of Leucaena leucocephala were offered as supplement at two levels, 25% (diet 2) and 50% (diet 3) of dry matter intake (DMI), replacing Hordeum jabatum hay diet. The basal hay diet without supplementation was diet 1. Rumen lquor was sampledone hour before, and one, three and five hours after the morning feeding. The sheep were subjected to digestibility trial. Sheep on diet 3 had higher (P

Published
2008

27. Steigerung des Gehaltes an nutzbarem Protein bei Körnerleguminosen mittels ökologisch konformer technischer Bearbeitungsverfahren zur Förderung von Gesundheit und Leistungsfähigkeit von Hochleistungskühen im ökologischen Landbau

Author

Bissinger, C., Steingaß, H., and Drochner, W.

Subjects
Feeding and growth, Dairy cattle
Abstract

Ziel dieses Projekts war durch ökologisch konforme Behandlungsmethoden den Anteil an pansenstabilem Protein bei Körnerleguminosen zu erhöhen, um so einem Defizit an nutzbarem Rohprotein am Dünndarm vorzubeugen. Dafür wurde die thermische Behandlung von Erbsen, der Zerkleinerungsgrad von Lupinen und die Wirkung zweier Ackerbohnensorten mit unterschiedlichem Tanningehalt untersucht. Es konnten z.T. positive Effekte bei den in vitro und in situ Untersuchungen nachgewiesen werden, die sich jedoch wenig auf die tierische Leistung auswirkten. Durch die Hitzebehandlung von Erbsen konnte eine Steigerung der Milchleistung um 1,36 kg erreicht werden, ohne Rückgang der Milchinhaltsstoffe. Es zeigte sich jedoch, dass dieser Leistungsanstieg eher auf eine bessere Energieverfügbarkeit zurückzuführen war. So ergab sich beim in situ Rohproteinabbau nur eine geringe Reduzierung der Abbaubarkeit durch die Behandlung. In vitro erhöhte sich der Anteil an pansenstabilem Protein, der Gehalt blieb jedoch insgesamt niedrig. Bei unterschiedlichem Zerkleinerungsgrad von Lupinen wurden Milchleistung und Milchinhaltsstoffe kaum beeinflusst und auch in den Stoffwechselversuchen zeigten sich nur geringe Unterschiede. Die Verdaulichkeit der Rohfaser war bei der Ration mit den gequetschten Lupinen höher, was u.a. an besseren Bedingungen für die zellulolytischen Bakterien gelegen haben mag durch den im Vergleich höheren und stabileren pH-Wert. Bei dem Vergleich zweier Ackerbohnensorten zeigte sich ein starker Einfluss der Sortenwahl auf das Pansenmilieu der Kühe, welches bei der Ration mit der tanninhaltigen Sorte Samba stabiler war. Dennoch waren Milchleistung und Fettgehalt für beide Rationen gleich. Es kam dagegen zum Anstieg des Eiweißgehalts bei der tanninfreien Sorte Valeria und der insgesamt hohe Harnstoffgehalt der Milch war bei der Sorte Valeria signifikant erhöht.

Published
2004

29. Modeling the Adequacy of Dietary Fiber in Dairy Cows Based on the Responses of Ruminal pH and Milk Fat Production to Composition of the Diet

Author

Zebeli, Q., Dijkstra, J., Tafaj, M., Steingass, H., Ametaj, B.N., Drochner, W., Zebeli, Q., Dijkstra, J., Tafaj, M., Steingass, H., Ametaj, B.N., and Drochner, W.

Abstract

The main objective of this study was to develop practical models to assess and predict the adequacy of dietary fiber in high-yielding dairy cows. We used quantitative methods to analyze relevant research data and critically evaluate and determine the responses of ruminal pH and production performance to different variables including physical, chemical, and starch-degrading characteristics of the diet. Further, extensive data were used to model the magnitude of ruminal pH fluctuations and determine the threshold for the development of subacute ruminal acidosis (SARA). Results of this study showed that to minimize the risk of SARA, the following events should be avoided: 1) a daily mean ruminal pH lower than 6.16, and 2) a time period in which ruminal pH is

Published
2008

30. Effects of Varying Dietary Forage Particle Size in Two Concentrate Levels on Chewing Activity, Ruminal Mat Characteristics, and Passage in Dairy Cows

Author

Zebeli, Q., Tafaj, M., Weber, I., Dijkstra, J., Steingass, H., Drochner, W., Zebeli, Q., Tafaj, M., Weber, I., Dijkstra, J., Steingass, H., and Drochner, W.

Abstract

The objective of this study was to investigate the effects of varying dietary forage particle size on chewing activity, ruminal mat characteristics, passage, and in situ ruminal and total tract digestion in dairy cows at a low- and high-concentrate inclusion. The experiment was designed as a 4 x 4 Latin square with a 2 x 2 factorial arrangement of treatments. Four ruminally cannulated late-lactating dairy cows were restrictively fed (17 kg of dry matter/d), in four 23-d periods, 1 of 4 different diets varying in the theoretical particle size (6 and 30 mm) of hay (56.6% NDF of dry matter) and in the levels (approximately 20 and 60%, dry matter basis) of a cereal-based concentrate. Ingredients of the ration were offered separately to the cows; dietary hay and low-level concentrate were offered twice daily at 0800 and 1600 h, whereas concentrate of the high-level treatment was offered in 4 meals a day at 0800, 1200, 1600, and 1900 h. This study showed that altering the forage particle size from 6 to 30 mm in a low-concentrate diet significantly increased the rumination time and ruminal mat consistency without affecting ruminal fermentation and passage. Further, particle breakdown and proportion of mat in the rumen increased, and in situ hay dry matter degradability improved, which in turn indicated a higher capacity of ruminal digesta to degrade fiber. On the other hand, increasing the forage particle size in a diet containing a high amount of concentrate increased the proportion of dry matter retained on a 1.18-mm screen from 37.5 to 42.0% and extended the rumination time by 100 min/d, as well as increasing the ruminal mat consistency. However, ruminal particle breakdown, short-term ruminal pH, fibrolytic capacity of the digesta, and proportion of mat in the rumen decreased. This was also reflected in a higher bailable liquid pool, increased fractional passage rate of solid digesta from the reticulorumen, and increased retention time in the hindgut, which in turn indi

Published
2007

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