The effect of different levels of crude protein on the pathophysiology of Haemonchus contortus infection in 2-year-old Boer dry does under confined conditions

Abstract

The effect of dietary protein supplementation on the pathophysiology of a single Haemonchus contortus infection in 2-year-old Boer dry does under confined conditions was examined. Twenty-four does were randomly confined in individual pens and allocated into three groups balanced by their liveweight. The goats in the Control group were offered a basal diet whereas goats in Treatments 1 and 2 were fed the basal diet plus 25% and 50% dietary protein increments, respectively. Each animal was orally administrated 100 H. contortus L3 larvae/kg liveweight on Day 0 of the experiment. The goat liveweights and FAMACHA scores were recorded at weekly intervals. Packed cell volumes, eosinophil percentage, haemoglobin concentration, total serum protein, globulin, and albumin concentrations were recorded on Days 0 and 14, and then at weekly intervals during the experiments. Faecal egg counts were measured on Days 0, 21, and then at weekly intervals thereafter. Antigen-specific IgA, IgG, and IgM titres were determined from Enzyme-linked immunosorbent assays tests on Days 0, 28, and at the termination of the experiment. The results of this study showed that a single H. contortus L3 infection did not cause pathogenic effects in 2-year-old Boer dry does. Dietary protein supplementation significantly lowered faecal egg count and significantly enhanced IgG titres (P < 0.05). However, the higher protein diets did not have any significant effects on liveweight, packed cell volumes, haemoglobin concentration, biological parameters (total serum protein, albumin, and globulin concentrations), and peripheral antibodies (IgA and IgM titres) between the treatments. Further investigations are required to clarify the role of protein supplementation to control H. contortus infection in goats.

The effects of protein supplementation and pasture maintenance on the growth, parasite burden, and economic return of pasture-raised lambs

“…These results are similar to those found in the current literature whereas lambs supplemented on pasture with soyhulls or DDGS had lesser FAMACHA eye scores and greater PCV values when compared with non-supplemented control lambs ( Felix et al, 2012 ). Conversely, in evaluating the effect of different levels of protein supplementation using oaten and lucerne chaff in Boer goats administered a single dose of H. contortus at a rate of 100 L 3 larvae/kg of live BW, protein supplementation did not have an effect on goat PCV ( Can et al, 2017 ). Furthermore, regardless of infection status (infected vs. non infected), supplemental protein has shown to improve lamb PCV ( Datta et al, 1998 ).…”

“…This is in support of the concept that regardless of whether the infection was experimentally induced or naturally acquired through grazing, lambs provided supplemental protein have lesser FEC when compared to non-supplemented lambs ( Abbott et al, 1988 ; Wallace et al, 1995 ; Strain and Stear, 2001 ). Similarly, Boer does artificially infected with a single dose of 100 H. contortus L 3 larvae/kg BW, demonstrated a negative correlation between FEC and supplemental protein such that FEC decreased linearly with increasing increments of supplemental protein in the basal diet, however, the H. contortus treatment used did not cause pathogenic effects in the Boer does ( Can et al, 2017 ). Under conditions where sheep are continuously ingesting H. contortus L 3 larvae from grazed forage, Bassetto et al (2018) demonstrated that giving grazing ewes supplemental protein decreased ewe FEC and improved the effect of a H. contortus specific vaccine (Barbervax).…”