Effect of saturated fatty acid supplementation on production and metabolism indices in heat-stressed mid-lactation dairy cows

Experimental objectives were to determine the effects of supplemental saturated fatty acids on production, body temperature indices, and some aspects of metabolism in mid-lactation dairy cows experiencing heat stress. Forty-eight heat-stressed Holstein cows were allocated into 3 groups (n=16/group)...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of dairy science 2010-09, Vol.93 (9), p.4121-4127
Hauptverfasser: Wang, J.P., Bu, D.P., Wang, J.Q., Huo, X.K., Guo, T.J., Wei, H.Y., Zhou, L.Y., Rastani, R.R., Baumgard, L.H., Li, F.D.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Experimental objectives were to determine the effects of supplemental saturated fatty acids on production, body temperature indices, and some aspects of metabolism in mid-lactation dairy cows experiencing heat stress. Forty-eight heat-stressed Holstein cows were allocated into 3 groups (n=16/group) according to a completely randomized block design. Three treatment diets consisted of supplemental saturated fatty acids (SFA) at 0 (SFA0), 1.5 (SFA1.5), or 3.0% (SFA3) of dry matter (DM) for 10 wk. Diets were isonitrogenous (crude protein=16.8%) and contained 1.42, 1.46, and 1.49 Mcal of net energy for lactation/kg of DM for the SFA0, SFA1.5 and SFA3 diets, respectively. The average temperature-humidity index at 0700, 1400 and 2200h was 72.2, 84.3, and 76.6, respectively. Rectal temperatures at 1400h were decreased with fat supplementation. Treatment did not affect dry matter intake (20.1±0.02kg/d), body condition score (2.72±0.04), body weight (627±16.1kg), or calculated energy balance (1.32±0.83Mcal/d). Saturated fatty acid supplementation increased milk yield, milk fat content, and total milk solids. Increasing fat supplementation decreased plasma nonesterified fatty acids (8%) but had no effect on other energetic metabolites or hormones. In summary, supplemental SFA improved milk yield and milk fat content and yield and reduced peak rectal temperatures in mid-lactation heat-stressed dairy cows. This demonstrates the remarkable amount of metabolic heat that is “saved” by energetically replacing fermentable carbohydrates with supplemental SFA.
ISSN:0022-0302
1525-3198
DOI:10.3168/jds.2009-2635