Objectives: To evaluate reproductive performance in commercial Polypay ewes fed supplemental vitamin E at the level recommended in the sheep NRC (1985) compared to the small ruminant NRC (2007) during spring mating

Bruns, K.

Held, J.E.

Wright, C.

Zelinsky, R.

English

Public Research Access Institutional Repository and Information Exchange

South Dakota State UniversityOpen PRAIRIE: Open Public Research Access InstitutionalRepository and Information ExchangeSouth Dakota State University Sheep ResearchReport, 2014Animal Science Field Day Proceedings andResearch Reports2014Effect of Vitamin E Supplementation onReproductive Performance in Spring Mated EwesJ.E. HeldSouth Dakota State UniversityR. ZelinskySouth Dakota State UniversityK. BrunsSouth Dakota State UniversityC. WrightSouth Dakota State UniversityFollow this and additional works at: http://openprairie.sdstate.edu/sd_sheepreport_2014Part of the Sheep and Goat Science CommonsThis Report is brought to you for free and open access by the Animal Science Field Day Proceedings and Research Reports at Open PRAIRIE: OpenPublic Research Access Institutional Repository and Information Exchange. It has been accepted for inclusion in South Dakota State University SheepResearch Report, 2014 by an authorized administrator of Open PRAIRIE: Open Public Research Access Institutional Repository and InformationExchange. For more information, please contact michael.biondo@sdstate.edu.Recommended CitationHeld, J.E.; Zelinsky, R.; Bruns, K.; and Wright, C., "Effect of Vitamin E Supplementation on Reproductive Performance in SpringMated Ewes" (2014). South Dakota State University Sheep Research Report, 2014. Paper 6.http://openprairie.sdstate.edu/sd_sheepreport_2014/6   SHEEP 2014-5  Effect of vitamin E supplementation on reproductive performance in spring mated ewes  J.E. Held, R. Zelinsky, K. Bruns, C. Wright  OBJECTIVES  To evaluate reproductive performance in commercial Polypay ewes fed supplemental vitamin E at the level recommended in the sheep NRC (1985) compared to the small ruminant NRC (2007) during spring mating.  MATERIALS AND METHODS  Mature commercial Polypay ewes (n = 81) were allocated to two treatment groups balanced by weight and supplemented with either 50 or 200 IU vitamin E for 5 weeks during the mating period (April 9 – May 14, 2008). Vitamin E was supplemented daily using a co-product based pellet fed at a rate of 1 lb per ewe. Mixed grass hay was available free-choice and the vitamin E level was 21 IU per pound. Four mature rams equipped with marking harnesses were used for each treatment group (1 ram:10 ewes). Rams selected for this study passed a breeding soundness exam including semen evaluation 2 wk prior to exposure. Breeding marks were observed daily and recorded by ewe eartag identification number. The source of ewes was from maternal lines selected for out of season reproductive success over several generations without exogenous hormones. Body weight, body condition scores, and serum vitamin E concentrations were determined prior to treatment and d 35 of the breed season. Vitamin E analyses for blood serum and feed ingredients were performed in a commercial laboratory located at a land-grant university.  Difference in least squares means for body weight, body condition scores (BCS), serum vitamin E and prolificacy that resulted from treatment were separated using the PDIFF option of SAS. Difference in least square means for reproductive performance including estrus activity and fertility data that resulted from treatment was separated by chi-square analysis.  RESULTS AND DISCUSSION  Reproductive performance data is given in Table 1. Level of vitamin E supplementation affected estrus activity (P = 0.0078) but not fertility or prolificacy. Even though estrus activity was higher for the vitamin E-50 ewes the result was a similar percent of ewes lambing and percent of lambs born and reared per ewe lambing. Out of season fertility and prolificacy data are similar to past reproductive performance results for this select line of ewes. As expected blood serum vitamin E concentration was higher (P = 0.001) for the vitamin E– 200 ewes after 5 wk, however all 12  treatment values were below 2 ug/ml the minimum serum vitamin E concentration suggested in the small ruminant NRC (2007) for adequacy.  The recommended vitamin E supplementation for breeding ewes using the sheep NRC (1985) is 6.8 IU per pound of dry matter, the small ruminant NRC (2007) suggests 2.4 IU vitamin E per pound of body weight for all classes of sheep. For ewes in this study the recommended daily supplemental vitamin E using sheep NRC (1985) guidelines is 34 IU and the small ruminant NRC (2007) computes to 336 IU.   Table 1. Reproductive performance of mature ewes supplemented with vitamin E at breeding  Vit E-50 Vit E-200 SEM P < Number of ewes exposed n = 41 n = 40        Initial wt (lb) 137.9 137.5 2.88 0.95 (BCS) (2.5) (2.4) 0.04 0.78      Ending wt (lb) 146.5 145.6 2.47 0.84 (BCS) (2.9) (2.9) 0.04 0.89      Serum Vit. E level (μg/ml)        Initial 0.74 0.79 0.02 0.22    Ending 0.92 1.59 0.05 0.001      Estrus Activity (%)    0.0078    None 2.5 24.4      1st 17d period 70.7 57.5      2nd 17d period 58.8 40.1    1st mark (41.6) (62.5)    Repeated (58.4) (37.5)      1st and 2nd period 35.0 17.1        Fertility (%)    0.95    Open 47.5 48.8      Lambed 52.5 51.2        Prolificacy per ewe lambing (%)        Lamb born 138 143 0.09 0.97    Lambs reared 133 138 0.08 0.78    13  

Effect of Vitamin E Supplementation on Reproductive Performance in Spring Mated Ewes

https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1005&context=sd_sheepreport_2014

Effect of Vitamin E Supplementation on Reproductive Performance in Spring Mated Ewes

Abstract

Similar works

Full text

Available Versions

Public Research Access Institutional Repository and Information Exchange