Effect of protein and energy levels on faecal progesterone concentration in Sabi ewes during oestrus cycle

摘要

ThestudyinvestigatedthereliabilityofusingfaecalprogesteroneasanindicatorofovarianactivityinSabiewesandhowthisisaffectedbyleveloffeeding.ThreedietswereformulatedtosimulatefeedavailabilityincommunalareasofZimbabwe,alownutrientdiet,amediumnutrientdietandahighnutrientdiet.Faecalandbloodsampleswerecollectednbsp;from18ewes(sixineachtreatment)onceeverytwodaysfortwooestruscyclesinordertodetermineprogesteronelevels.Diethadasignificanteffectontheplasmaprogesteroneconcentration(P0.05)andanonsignificanteffectonfaecalprogesteroneconcentration(P0.05).Onalldiets,faecalprogesteroneconcentrationswerehigherthanplasmaprogesteroneconcentration.Thepatternoffaecalandplasmaprogesteroneconcentrationwerepositivelycorrelatedinewesonamediumnutrientdiet(r=0.920,P0.05)thanonalownutrientdietandahighnutrientdiet(r=0.6881,P0.05andr=0.50,P0.05).Response-relationshipbetweenfaecalandplasmaprogesteroneconcentrationprofileswasnon-linear(R-square=0.25,P0.05)forewesonahighnutrientdietandlinearforalownutrientdietandamediumnutrientdiet(R-square=0.46,P0.05andR-square=0.84,P0.05).Faecalprogesteronecanbeusedasanalternativemethodofmonitoringtheovarianactivityinruminantanimalsonamediumnutrientleveloffeeding.