Anthelmintic efficacy in strongyles of horses in Northern Minas Gerais, Brazil

The intensive use of anthelmintics has resulted in resistant parasite populations in horses. The objective of this trial was to evaluate the anthelmintic efficacies of the anthelmintics fenbendazole, ivermectin and abamectin in 24 horse farms in Northern Minas Gerais. Egg counts per gram of faeces (EPG) were performed individually in 619 animals. Animals presenting EPG counts greater than or equal to 150 were used in the tests on faecal egg count reduction (FECR), totalling 436 equines. These animals received the anthelmintics, fenbendazole, ivermectin, and abamectin. Faeces were collected 14 days after the administration of anthelmintics to perform the EPG. Pre- and post-treatment EPG counts were used to calculate the FECR for each anthelmintic group, and faecal culture was used to identificy of the strongyles. The resistance status was evaluated based on the FECR and LCL95%. Fenbendazole was effective in 11 (45.8%) of the horse farms. Ivermectin was effective in 17 (77.3%) and abamectin in 17 (74%) of the farms; side-resistance was detected in 3 (12.5%) of the farms. Intestinal strongyle resistance to anthelmintics was observed in 14 (58.3%) of the farms. Cyathostomin larvae were found in 100% of the farms, Strongylus vulgaris in 13 (54.2%), and S. equinus in 3 (12.5%). Only cyathostomins larvae were detected post-treatment with ivermectin and abamectin.

Feeding Behavior of Mangalarga Marchador Weanlings Fed Sorghum Silage Versus Grass Hay

Mangalarga Marchador foals in Minas Gerais, Brazil, are usually weaned during the dry season, when there is a scarcity of forage. Although sorghum silage has been used to feed weanlings, the effect on their feeding behavior in comparison with grass hay has not been reported. Twelve Mangalarga Marchador weanlings were randomly assigned to two groups of six animals: SS: sorghum silage; VH: Vaquero hay. Both groups received commercial concentrate in the proportion of 1.2 kg.100 kg^-1 of the live weight and forage ad libitum. The animals were filmed for 48 hours, being timed: forage intake time, water intake time (WIT), concentrate intake time, and leisure time (LT). Tukey's test was used to compare the parameters between SS and VH groups. Forage intake time and WIT were higher (P < .05) in VH group because the hay had low moisture content, stimulating water intake. Feeding behavior of weanlings kept in individual stalls and consuming sorghum silage was different than those consuming grass hay, providing less forage intake time and longer LT spent in comparison with VH.

Effect of Supplementation of Sorghum Silage in Weanling Fillies During the Dry Period in Brazil

Young horses reach nearly 90% of their final height in the first year of life. However, to achieve their genetic potential, it is necessary to receive adequate nutrition during this period of rapid growth. The objective of this study was to evaluate the effect of supplementation of sorghum silage during a period of limited pasture forage availability, on the body development, and health of Mangalarga Marchador (MM) weanling fillies. Fourteen healthy MM 6-month-old fillies were randomly assigned to one of two groups: GS (consuming silage) and GH (consuming grass hay (Cynodon spp) in addition to 1.5% of body weight (BW) in dry matter (DM) of a fortified corn-based concentrate (17% CP [crude protein]), which was fed in individual stalls divided into two feedings/day for both groups. After concentrate feedings, the experimental groups remained loose in drylot pens of 50 m², where the assigned forages were fed ad libitum with free access to salt and water. Group feed intake of the forages was recorded. It was assumed they were consuming a forage:concentrate ratio of 50:50. To assess development, the animals were weighed and measured for height at the withers and croup, body length, girth, and cannon bone circumference. The physical condition of animals, including BW, rectal temperature, mucous membrane color, and body condition score were assessed as well as serum biochemical analyses of creatinine, urea, total protein, gamma glutaminotransferase, aspartate aminotransferase, alkaline phosphatase, glucose, magnesium, calcium, and phosphorus concentrations were evaluated. The weights, morphometric measurements, clinical evaluation, and blood collections were done on the first day and every 21 days during the 84 days trial period. The growth performance and serum were subjected to analysis of variance for repeated measures, factoring treatment, and collection period. Despite higher (P < .05) DM and CP intakes by the GH fillies than those GS, there were no treatment effects (P > .05) on any of the development or health parameters measured. The use of sorghum silage as forage source for 84 days during the dry season had no negative impact on the body development and health of MM fillies (6-9 months of age) that were also fed 1.5% BW of a commercial concentrate balanced for growth.