Reproductive performance and serum fatty acid profiles of underdeveloped beef heifers supplemented with saturated or unsaturated rumen bypass fat compared to an isocaloric control
| Autor: | T. A. Burns, Susan K. Duckett, David W Schafer, Nathan M. Long |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
chemistry.chemical_classification
medicine.medical_specialty animal structures Cholesterol animal diseases Fatty acid Biology Cattle feeding chemistry.chemical_compound Endocrinology Blood serum chemistry Blood chemistry Internal medicine Saturated fatty acid medicine Animal Science and Zoology Animal nutrition Unsaturated fatty acid Food Science |
| Zdroj: | The Professional Animal Scientist. 30:502-509 |
| ISSN: | 1080-7446 |
| DOI: | 10.15232/pas.2014-01311 |
| Popis: | Research involving fat supplementation to heifers has shown positive reproductive effects, but the effect of lipid composition has had little investigation. Heifers (n = 118) were blocked by age, breed, and BW and pen-fed alfalfa hay. Heifers were individually fed 1 of 3 isocaloric supplements: control (CON) or either half the CON diet with 0.2 kg of a rumenprotected unsaturated fatty acid source (USFA) or a rumen-protected saturated fatty acid source (SFA) fed 5 d/wk. Heifers received treatments for 3 wk before starting the 7-d controlled intravaginal drug release estrus synchronization protocol. Heifers remained on treatment for 28 d after AI. Pregnancy was determined at d 30 post-AI via transrectal ultrasonography and by rectal palpation at 150 d post-AI. Serum progesterone and leptin were measured by RIA and serum triglycerides; cholesterol was measured by colorimetric procedures. Heifers BW gain during supplementation was similar (P = 0.35) between treatment groups (32 ± 2 kg). Percentage of heifers cycling tended to be less (P = 0.08) for USFA heifers compared with CON and SFA treatments (36 vs. 55 and 56%, respectively). Pregnancy rates by AI of heifers detected in estrus were similar (P = 0.35) between treatments. Serum total and specific fatty acids, cholesterol, and triglycerides were greater (P < 0.05) at d 21 and 56 in fat-supplemented heifers compared with CON heifers. At d 56 of treatment, USFA had greater (P < 0.05) plasma leptin compared with SFA, with CON heifers having further reduced serum leptin concentration. Feeding rumen-protected fats to heifers increased circulating lipid and leptin, but did not influence reproduction rates. |
| Databáze: | OpenAIRE |
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