Effects of inert fat on energy balance, plasma concentrations of hormones, and reproduction in dairy cows

• Published in: Journal of dairy science Vol. 76; no. 9; pp. 2664 - 2673
• Main Authors: Spicer, L.J, Vernon, R.K, Tucker, W.B, Wettemann, R.P, Hogue, J.F, Adams, G.D
• Format: Journal Article
• Language: English
• Published: Savoy, IL Am Dairy Sci Assoc 01.09.1993; American Dairy Science Association
• Subjects: Animals; BALANCE DE ENERGIA; BILAN ENERGETIQUE; Biological and medical sciences; Body Weight; Cattle - physiology; CHOLESTEROL; Cholesterol - blood; CICLO ESTRAL; COLESTEROL; CORPS GRAS; CYCLE OESTRAL; DIETA; Dietary Fats - pharmacology; Energy Metabolism; Estrus - physiology; Female; Fundamental and applied biological sciences. Psychology; GRASAS; Hormones - blood; INGESTION DE PIENSOS; Insulin-Like Growth Factor I - metabolism; INSULINA; INSULINE; Lactation - physiology; Mother. Fetoplacental unit. Mammary gland. Milk; OVULACION; OVULATION; Ovulation - physiology; PESO; PLASMA SANGUIN; PLASMA SANGUINEO; POIDS; Pregnancy. Parturition. Lactation; PRISE ALIMENTAIRE (ANIMAUX); PROGESTERONA; PROGESTERONE; Progesterone - blood; REGIME ALIMENTAIRE; RENDEMENT LAITIER; RENDIMIENTO LECHERO; Reproduction - physiology; VACAS LECHERAS; VACHE LAITIERE; Vertebrates: reproduction; Lactation; Somatomedin C; Ox; Lipids; Feeding; Energy balance; Reproduction; Vertebrata; Mammalia; Diet; Female; Artiodactyla; Ungulata
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.s0022-0302(93)77602-x

The objective was to determine the effects of dietary inert fat on estimated energy balance, hormones in plasma, and reproduction during early lactation. From wk 0 to 12 postpartum, 14 pluriparous Holstein cows were fed individually a TMR, and blood samples were taken twice weekly for quantification of IGF-I, progesterone, and cholesterol. During wk 5 to 12, one-half of the cows remained on the TMR, and the other half were fed the TMR containing inert fat at 1.8% of dietary DM. Estrous behavior was monitored twice daily, and body condition scores were recorded every 4 wk. Cows fed inert fat between wk 5 and 12 postpartum had similar concentrations of IGF-I in plasma but greater luteal phase progesterone secretions than cows fed the control diet. Total cholesterol in plasma also was greater in cows fed inert fat than in cows fed the control diet. Intervals to first, second, and third ovulation or estrus did not differ among cows fed control or inert fat diets. Body condition scores, daily DMI, and milk production were not affected by dietary inert fat. Inert fat fed to cows between wk 5 and 12 postpartum did not affect ovulatory activity but may enhance luteal activity