title: Effects of differential supplementation of fatty acids during the peripartum and breeding periods of Holstein cows: I. Uterine and metabolic responses, reproduction, and lactation.
abstract: The objectives were to evaluate the effects of differential timing of supplementation of different Ca salts (CS) of fatty acids (FA) on FA profiles of cotyledonary-caruncular tissues, metabolic status, uterine health, pregnancy, pregnancy losses after 2 artificial inseminations (AI), and milk yield. Holstein cows (n=1,380) were assigned randomly to be fed either CS of palm oil (PO) or safflower oil (SO) from 30 d prepartum until 30 d postpartum (dpp) and further randomized to receive either CS of PO or fish oil (FO) from 30 to 160 dpp. Supplementation of CS of FA was at 1.5% of dietary dry matter. Tissues (n=23) and blood (n=32) were collected from a subsample of cows. Blood was collected daily from parturition to 10 dpp and three times weekly thereafter until 30 dpp for analyses of PGF2α metabolite, nonesterified FA, β-hydroxybutyric acid, blood urea nitrogen, and glucose. Cows were evaluated once between 8 to 10 dpp for cervical discharge type. At 43 dpp, cows received 2 injections of PGF2α 14 d apart, followed 14 d later by injections of GnRH at 7 d before and 56 h after an injection of PGF2α with AI at 16 h after the second GnRH injection. All cows received intravaginally a controlled internal drug-releasing device, containing 1.38 g of progesterone, at 18 d after the first AI followed 7 d later by removal of the device and injection of GnRH. Nonpregnant cows at 32 d after AI were injected with PGF2α, followed 56 h later with a GnRH injection and second AI 16 h thereafter. Cows diagnosed pregnant after both AI were re-examined at 60 d of pregnancy to determine pregnancy losses. Milk weights were recorded monthly for all cows. Caruncular n-6:n-3 FA ratio was greater in cows fed SO. Plasma concentrations of metabolites and frequency of cervical discharge type did not differ between PO- and SO-fed cows. Plasma PGF2α metabolite was greater in SO-fed cows at 4 and 7 dpp. Pregnancy per AI at 32 and 60 d post first AI was not affected by diets, but pregnancy loss was less in FO-fed cows. At second AI, pregnancy was greater in FO-fed cows at 32 d and in SO-FO-fed cows at 60 d post AI. Pregnancy loss after second AI was not affected by diets. Overall pregnancy per AI was greater in cows fed SO followed by FO at 60 d of pregnancy and pregnancy loss was reduced in FO-fed cows. Monthly milk yield was greater (0.7 kg/d) in SO-fed cows. In conclusion, strategic feeding of CS of FA during transition and breeding periods can benefit fertility and milk production of lactating dairy cows.
authors.affiliation: Department of Animal Sciences, University of Florida, Gainesville, FL 32611, USA.
authors.forename: F T
authors.initials: FT
authors.lastname: Silvestre
authors.forename: T S M
authors.initials: TS
authors.lastname: Carvalho
authors.forename: N
authors.initials: N
authors.lastname: Francisco
authors.forename: J E P
authors.initials: JE
authors.lastname: Santos
authors.forename: C R
authors.initials: CR
authors.lastname: Staples
authors.forename: T C
authors.initials: TC
authors.lastname: Jenkins
authors.forename: W W
authors.initials: WW
authors.lastname: Thatcher
mesh_terms: D000821:Animal Feed; D000818:Animals; D001947:Breeding; D002118:Calcium / Q000008:administration & dosage; D002417:Cattle / Q000378:metabolism / Q000502:physiology*; D019587:Dietary Supplements; D005227:Fatty Acids / Q000008:administration & dosage*; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage; D007315:Insemination, Artificial / Q000662:veterinary; D007774:Lactation / Q000502:physiology*; D000073878:Palm Oil; D058725:Peripartum Period; D010938:Plant Oils / Q000008:administration & dosage; D011247:Pregnancy; D018873:Pregnancy Rate; D012098:Reproduction / Q000502:physiology*; D012450:Safflower Oil / Q000008:administration & dosage; D013997:Time Factors; D014599:Uterus / Q000502:physiology*
chemical_list: D005227:Fatty Acids; D005395:Fish Oils; D010938:Plant Oils; D000073878:Palm Oil; D012450:Safflower Oil; D002118:Calcium