Effect of pectin, lecithin, and antacid feed supplements (Egusin®) on gastric ulcer scores, gastric fluid pH and blood gas values in horses

BACKGROUND: The objectives of this study were to evaluate the effects of two commercial feed supplements, Egusin 250(®) [E-250] and Egusin SLH(®) [E-SLH], on gastric ulcer scores, gastric fluid pH, and blood gas values in stall-confined horses undergoing feed-deprivation. METHODS: Nine Thoroughbred horses were used in a three-period crossover study. For the three treatment groups, sweet feed was mixed with E-250, E-SLH, or nothing (control group) and fed twice daily. Horses were treated for 21 days, then an additional 7 days while on an alternating feed-deprivation model to induce or worsen ulcers (period one). In periods two and three, horses (n=6) were treated for an additional 7 days after feed-deprivation. Gastroscopies were performed on day -1 (n=9), day 21 (n=9), day 28 (n=9) and day 35 (n=6). Gastric juice pH was measured and gastric ulcer scores were assigned. Venous blood gas values were also measured. RESULTS: Gastric ulcers in control horses significantly decreased after 21 days, but there was no difference in ulcer scores when compared to the Egusin® treated horses. NG gastric ulcer scores significantly increased in E-250 and control horses on day 28 compared to day 21 as a result of intermittent feed-deprivation, but no treatment effect was observed. NG ulcer scores remained high in the control group but significantly decreased in the E-SLH- and E-250-treated horses by day 35. Gastric juice pH values were low and variable and no treatment effect was observed. Mean blood pCO(2) values were significantly increased two hours after feeding in treated horses compared to controls, whereas mean blood TCO(2) values increased in the 24 hour sample, but did not exceed 38 mmol/l. CONCLUSIONS: The feed-deprivation model increased NG gastric ulcer severity in the horses. However, by day 35, Egusin(®) treated horses had less severe NG gastric ulcers compared to untreated control horses. After 35 days, Egusin(®) products tested here ameliorate the severity of gastric ulcers in stall-confined horses after feed stress

Reproduction in high body condition mares with high versus low leptin concentrations

Previous results from our laboratory indicated that a majority of mares with high body condition scores (BCS) displayed estrous cycles or had considerable follicular activity during the winter. Among these high BCS mares, about 35% of them exhibited a persistent hyperleptinemia and hyperinsulinemia. The current experiment was designed to compare the reproductive characteristics of high BCS mares with hyperleptinemia to those with normal (low) plasma concentrations of leptin during the winter and the first estrous cycle (or the first full cycle encountered for those already cycling). Light horse mares with high BCS (6-8.5) were assigned to groups based on leptin concentrations (8/group): low (\u3c5 ng/mL) and high (\u3e10 ng/mL). Beginning 7 January, mares were assessed every 3 d for follicular activity and then daily once a follicle \u3e25 mm was detected. Mares were subsequently monitored through their first and second ovulations. Leptin concentrations remained higher (P \u3c 0.001) in mares in the high leptin group over the duration of the experiment. Also, high leptin mares had greater (P \u3c 0.0001) insulin response to glucose infusion and a faster (P \u3c 0.05) rate of glucose clearance. One mare with high leptin and three mares with low leptin had progesterone concentrations indicative of the presence of a corpus luteum at the onset of the experiment. Plasma concentrations of LH, FSH, and progesterone did not differ between groups (P \u3e 0.1) during the first estrous cycle occurring after 7 January. Date of first ovulation after 7 January and interovulatory interval were similar (P \u3e 0.1) for the two groups, as were estimates of follicular numbers on the ovaries (small, medium, and large; P \u3e 0.1). It is concluded that the perturbations in leptin and insulin secretion observed in some high BCS mares are not associated with alterations in ovarian activity or the estrous cycle during winter and into the period of vernal transition. © 2006 Elsevier Inc. All rights reserved