Supplementation with rumen-protected L-arginine-HCl increased fertility in sheep with synchronized estrus.

Abstract

The aim of the present study was to evaluate the effects of L-arginine-HCl supplementation on ovulation rate, fertility, prolificacy, and serum VEGF concentrations in ewes with synchronized oestrus. Thirty Suffolk ewes with a mean body weight of 45 ± 3 kg and a mean body condition score (BCS) of 2.4 ± 0.28 were synchronized for estrus presentation with a progestin-containing sponge (20 mg Chronogest® CR) for 9 days plus PGF2-α (Lutalyse; Pfizer, USA) on day 7 after the insertion of the sponge. The ewes were divided into two groups; i.e., a control group (n = 15) that was fed on the native pasture (basal diet) and an L-arginine-HCl group (n = 15) that received 7.8 g of rumen-protected L-arginine-HCl from day 5 of the sponge insertion until day 25 after mating plus the basal diet. The L-arginine-HCl was administered daily via an esophageal probe between days 5 and 9 of the synchronization protocol and every third day subsequently. Blood samples were drawn from the jugular vein every 6 days throughout the entire experimental period. The results revealed that the L-arginine-HCl supplementation increased fertility during the synchronized estrus (P = 0.05). However, no effects were observed on the final BCS (P = 0.78), estrus presentation (P = 0.33), multiple ovulations (P = 0.24), prolificacy (P = 0.63), or serum VEGF concentration. In conclusion, L-arginine-HCl supplementation during the period used in this study increased fertility in sheep with synchronized estrus possibly due to improved embryo-fetal survival during early pregnancy.

• Authors: Julio Agustín Ruiz de Chávez, Adrian Guzmán, Diana Zamora-Gutiérrez, Germán David Mendoza, Luz María Melgoza, Sergio Montes, Ana María Rosales-Torres
• Journal: Tropical animal health and production (Trop Anim Health Prod) Vol. 47 Issue 6 Pg. 1067-73 (Aug 2015) ISSN: 1573-7438 [Electronic] United States
• PMID: 25991464 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Arginine

Topics

• Animals
• Arginine (administration & dosage, pharmacology)
• Dietary Supplements
• Estrus (drug effects)
• Estrus Synchronization
• Female
• Fertility (drug effects)
• Ovulation (drug effects)
• Pregnancy
• Reproduction (drug effects)
• Rumen (metabolism)
• Sheep