The aim of this study was to evaluate the effects of selenium and copper on oxidative stress and its performance in lambs experimentally infected with Haemonchus contortus. Twenty-eight five-months old lambs were experimentally infected by the oral route with 5000 third-stage infective larvae and allocated into four groups, i.e., untreated animals, animals treated intramuscularly with sodium selenite (0.2 mg kg(-1)), animals treated subcutaneously with copper (3.5 mg kg(-1)), and animals treated with sodium selenite (IM; 0.2 mg kg(-1)) and copper (SC; 3.5 mg kg(-1)). These animals received oat hay (Avena sativa) and commercial concentrate, totaling 15% of crude protein, 30% being derived from oat hay and 70% of the concentrate. Lipid peroxidation, antioxidant enzymes, eggs per gram of feces (EPG) and body weight were assessed on the day of infection and after 20, 40, 60 and 80 days post-infection. The number of H. contortus adults was assessed at the end of the experiment. The selenium associated or not with copper reduced the effects of oxidative stress caused by infection. The groups supplemented with copper had increased body weight, and the combination of these two minerals reduced the EPG and number of H. contortus adults in lambs. The use of selenium associated with copper may help the control of infection by H. contortus.

Among the parasites that affect pigs, Ascaris suum stands out for causing the greatest losses to livestock production systems. This parasite can be monitored during the slaughter of animals through the identification of "milk spots" or white patches on the liver caused by its larval migration. However, infection in the herd is usually subclinical, which is why the presence of this parasite in industrial pig production has been overlooked. The aim of the study was therefore to evaluate the occurrence of milk spots on the liver of animals slaughtered in the micro-region of Ponte Nova in the Zona da Mata -Minas Gerais, Brazil, and to associate these lesions with the time of year, herd size and source of origin of the animals. An evaluation was made of 1,069 lots, totaling 108,073 animals, based on data extracted from the Federal Inspection Service. The animals were slaughtered during the period of January 2011 to June 2013. Out of the total number of slaughtered animals, 10,535 (9.75%) tested positive for these lesions. Therefore, veterinarians and producers should be warned about the inefficiency of the deworming protocols that are used, and the need to develop and/or review control strategies for this parasite in production systems.

BackgroundGastrointestinal nematodes cause significant economic losses in the sheep industry, with frequent reports of anthelmintic resistance. Therefore, alternative methods to control these parasites are necessary. Thus, the aim of the present study was to assess the effect of treatment with selenium and copper on the protein profile of sheep that were experimentally infected with Haemonchus contortus.MethodsTwenty-eight lambs were experimentally infected with H. contortus and divided into four experimental groups as follow: G1 - untreated animals; G2 - treated with sodium selenite; G3 - treated with copper; G4 - treated with sodium selenite and copper. The serum protein, body weight and egg count per gram of feces (EPG) were assessed at the baseline and after 20, 40, 60 and 80 days. The parasite burden was assessed 80 days after the beginning of the experiment.ResultsHigher levels of total protein and gamma globulin were observed in the lambs treated with sodium selenite and copper on D80. Copper acted as a growth promoter. The copper-supplemented groups exhibited higher daily and total weight gain. The association of selenium and copper altered the protein profile of sheep. Copper and selenium supplementation reduced EPG and worm burden at the end of the experiment. To the best of our knowledge, this is the first study to demonstrate the positive effect of the combined parenteral supplementation of Se and Cu on H. contortus infection.ConclusionsThis injectable supplementation could be used as an auxiliary method to control H. contortus in sheep.

No abstract

The aim of this study was to evaluate adenosine deaminase (E-ADA) activity in sera of lambs experimentally infected with Haemonchus contortus. We used 12 lambs divided into 2 groups; Group A had 5 healthy, non-infected animals (control) and Group B had 7 healthy animals infected with H. contortus . Lambs were infected orally with 500 larvae (L3) per animal every 2 days, for a period of 20 days, and later the infection was confirmed by examination of feces (eggs per gram [EPG] via fecal egg count). Blood collection was performed at days 0, 20, 40, 60, and 80 post-infection (PI) for analysis of E-ADA activity. Animals in Group A showed negative EPG throughout the experiment unlike those from Group B that had elevated EPG counts. E-ADA activity was reduced in the serum of animals infected with H. contortus when compared to non-infected controls at days 20, 40, 60, and 80 PI. Therefore, it is concluded that infection with H. contortus influences the E-ADA activity in lambs.