Protein supplementation in the first 100 days of gestation fails to enhance resistance of weaned Merino lambs against Haemonchus contortus

Dietary protein degradability effect on performance of lambs experimentally infected with Haemonchus contortus and Trichostrongylus colubriformis

The study investigated the effects of dietary protein degradation rate on growth performance and immune response of crossbred Dorper × short-tail Han ram lambs experimentally infected with Haemonchus contortus and Trichostrongylus colubriformis. Eighteen lambs were randomly assigned to three dietary treatments, rapidly degradable protein (RDP), moderately degradable protein (MDP), and slowly degradable protein (SDP) diets. Feed intake and body weight of the lambs were recorded weekly until 42 days post-infection. The fecal egg count (FEC), FAMACHA scores, and immunoglobulins (IgG, IgM and IgA) were also monitored during the experimental period. A metabolic trial was conducted to assess apparent digestibility and volatile fatty acids were also determined. The lambs in SDP and MDP groups had higher feed, nutrient intake, weight gain, and feed efficiency than those in the RDP group. Feed conversion ratio (FCR) of the lambs in RDP group was higher than those in the SDP and MDP groups. A significant (P < 0.001) decrease in FEC was observed in the SDP and MDP groups. Dietary treatment had no significant effect on FAMACHA scores and concentration of serum antibodies. Concentration of acetic acid was higher (P < 0.013) in the lambs fed RDP than those fed the SDP and MDP diets. The lambs fed SDP diet had higher apparent digestibility than those fed the RDP diet. The poor performances in RDP group could be overcome by including SDP that ensures adequate post-ruminal protein supply reaching the small intestine.

Influence of metabolizable protein and minerals supplementation on detrimental effects of endoparasitic nematodes infection in small ruminants

Endoparasitic nematode infection could have negative impacts on performances of sheep and goats. However, supplementary protein and minerals can also affect nematodes. This paper reviews present information on the importance of protein and minerals supplementation as means to control nematode infection in small ruminants. Protein supplementation seems to improve host resilience by diverting metabolizable protein (MP) towards dealing with detrimental effects of the infection and thus improve production and reproductive performances of animal. A large body of evidence shows that supplementation of copper, iron, and zinc can also enhance host resistance against nematode infection as shown by decreased fecal egg count (FEC) and worm burdens. As such, protein and mineral supplementations can play a major role in sustainable control of parasitic nematode infection and thus reduce reliance on chemotherapic drugs.

Can the amount of digestible undegraded protein offered to ewes during late pregnancy affect the performance and immune response of their offspring to gastrointestinal nematodes?

Maternal nutrition during pregnancy is a major environmental influence on foetal development with consequent effects on postnatal performance. We hypothesised that the level of intake of digestible undegraded protein (DUP) by the dam in late pregnancy would impact on the effectiveness of the immune response by offspring to gastrointestinal nematode infection. Eighty-five twin/triplet-bearing ewes, which were indoors from mid-pregnancy, were randomly assigned to 4 treatment groups for the final 6 weeks of pregnancy. Treatments were silage plus one of two iso-energetic and iso-nitrogenous concentrates (differing in DUP concentration; 29 and 94g/kg DM) offered at one of two feed levels (18/30 and 24/35kg in total for twin/triplet-bearing ewes, respectively). Ewes with triplets had one lamb removed at birth so that all ewes nursed 2 lambs when put to pasture as one flock in a 5-paddock rotational grazing system; all lambs were slaughtered after 29 weeks. Faecal egg count (FEC) and levels of serum IgA and IgE specific for Teladorsagia circumcincta were assessed for all lambs at various time points between 10 weeks of age and slaughter. Animal performance (live weight, live-weight gain, carcass weight) was recorded for all lambs. Worm burden at slaughter was determined for a sample of 12 lambs from each treatment. Nematodirus spp. FEC, 'other strongyles' FEC, and serum IgA and IgE specific for T. circumcincta were unaffected either by the concentration of DUP in the concentrate or by the level of concentrate offered to ewes in late pregnancy (P>0.1). Likewise, the dietary regime of the dams had no effect on lamb performance (P>0.1). It is concluded that increasing the DUP intake of ewes in late pregnancy had no effect on the immune response of their offspring to gastrointestinal nematode infection acquired through grazing naturally infected pasture.

Effect of Moxidectin Treatment at Peripartum on Gastrointestinal Parasite Infections in Ewes Raised under Tropical Andes High Altitude Conditions

This study tested the impact of moxidectin at peripartum on nematode fecal egg count (FEC) and clinical parameters on ewes in the high altitude tropical Andes of Colombia. FEC and clinical evaluations were performed on 9 occasions in 43 naturally infected ewes before and during gestation and after lambing. Moxidectin (Mox, 200 µg kg(-1)) was applied at late pregnancy (T 1, n = 15) or 48 hours after parturition (T 2, n = 14). 14 untreated ewes served as controls (C). Suckling lambs (n = 58) remained untreated and underwent four clinical and parasitological evaluations until 8 weeks after birth. Mox efficacy equaled 99.3% (T 1) and 96.9% (T 2). Highest mean FEC value reflecting periparturient nematode egg rise (PPER) was recorded in C ewes at 4-6 weeks after lambing. Significant FEC reductions were found in T 1 (94.8%) and T 2 (96.7%) ewes (p < 0.05). All lambs showed a significant and ewes-group independent increase in FEC before weaning (p < 0.05). Clinical parameters (anemia and diarrhea) showed time- and treatment-related differences (p < 0.05). Monitoring of FEC and clinical parameters linked to gastrointestinal parasite infections allowed demonstrating that postpartum or preweaning are two critical periods to nematode infection for sheep raised under tropical Andes high altitude conditions. Use of Mox as anthelmintic treatment prevented PPER.