Metabolites and Hormones as Indicators of Postpartum Reproductive Efficiency of Supplemented Pasture- Based Friesian Dairy Cows at Kalro, Lanet, Nakuru County,Kenya
| dc.contributor.author | Indetie, Annah Hoka | |
| dc.date.accessioned | 2026-03-03T10:28:33Z | |
| dc.date.available | 2026-03-03T10:28:33Z | |
| dc.date.issued | 2025-10 | |
| dc.description | A Thesis Submitted In Fulfillment Of the Requirements for the Award of the Degree of Doctor of Philosophy (Animal Physiology) in the School of Pure and Applied Sciences of Kenyatta University. October 2025 Supervisors Michael Gicheru Syprine Otieno | |
| dc.description.abstract | High-yielding dairy cows experience a phase of substantial tissue catabolism in the early postpartum period due to a negative nutritional balance that is partially brought on by inadequate fodder quality and quantity. A significant obstacle to increasing cow production is the requirement for feed ingredients during late pregnancy to sustain the growth of the fetus and lactation following parturition. Metabolic signals and regulatory hormones are linked to the mechanism for the restart of ovulation. The ability of metabolites and hormone levels to predict nutritional condition and postpartum reproductive efficiency in dairy cows in Kenya is unknown. Programs for breeding and feed formulation may benefit from this data. The goal of the study was to determine the role of hormones and feed metabolites as markers of postpartum reproductive efficiency. Twenty cows were supplemented with total mixed ration feed blocks (TMR) twice daily while grazing on Elba rhodes grass for eight hours/day. Ten in-calf cows served as the control; they grazed on Elba rhodes grass for eight hours without supplementation. Body condition scoring was done every fifteen days. Gestation period, calf sex, milk production, and days to postpartum heat were recorded. Analysis of feeds' chemical composition and digestibility were conducted. Skimmed milk was prepared and kept at 4°C until time for laboratory analysis. Jugular venipuncture was used to obtain blood samples into ethylene diamine tetraacetate polystyrene tubes. The blood was spun at 1500 rpm for 15 minutes to release plasma which was stored at -20°C until time for laboratory analysis. Radioimmunoassay was used to track postpartum ovarian activity using skimmed milk. Data was analyzed using statistical analysis system (2010). The results showed that neutral detergent fibre of feeds used in this study ranged from 39.5±0.04 % to 41.7±6.7%. Nutrient components that highly positively correlated with metabolisable energy were protein, methionine, and lysine. Supplementation significantly influenced (p<0.05) metabolite and hormonal levels. Body condition score at calving was higher among test cows (2.9±0.1) than the control (2.5±0.1). Test cows produced significantly higher percentage (80%) of female calves than the control (20%). The test cows took significantly shorter gestation period (278.4±1.0 days) than the control (284.1±1.1 days). The test cows registered higher mean daily milk yield (9.1 L) than the control (5.3 L). Test cows cycled earlier (50.4±0.90 days) than the control (62.7 ±2.0 days). The test cows had significantly less number of insemination to conception (1.35) than the control cows (2.7). Insulin like growth factor-1(IGF) and insulin reduced with advanced pregnancy, with the test cows having significantly higher values than the control. Glucose decreased with advanced pregnancy reaching threshold day 15 postpartum with the test cows having higher values. Commencement of luteal activity concided with low levels of non-esterified fatty acids (NEFA) and β hydroxybutyrate (BHB). Luteal activity progesterone was positively highly correlated to IGF-1(p < 0.001, r2=0.672), and glucose (p < 0.001, r2=0.634) but highly negatively correlated to NEFA (P=0.001, r2 = -0.689) and BHB (P=0.001, r2=0.679). Glucose, NEFA, IGF-1, and BHB are good indicators of postpartum reproductive efficiency. Data generated from this study is useful in reducing calving interval. Supplementation of in calf cows with quality feed is recommended to reduce calving intervals. | |
| dc.identifier.uri | https://ir-library.ku.ac.ke/handle/123456789/32633 | |
| dc.language.iso | en | |
| dc.publisher | Kenyatta University | |
| dc.title | Metabolites and Hormones as Indicators of Postpartum Reproductive Efficiency of Supplemented Pasture- Based Friesian Dairy Cows at Kalro, Lanet, Nakuru County,Kenya | |
| dc.type | Thesis |