Gastrointestinal nematodes pose a threat to animal health and affect farmers by negatively impacting farm management.

Introduction: Gastrointestinal nematodes pose a threat to animal health and affect farmers by negatively impacting farm management. Material and Methods: The study was conducted on a sheep farm with suspected reductions in the efficacies of anthelmintics. Efficacy was determined using in vivo faecal egg count reduction, in vitro egg hatch (EHT) and larval development (LDT) tests. In the first phase, 60 sheep were equally split into six groups. Group 1 received the recommended dose of albendazole (ALB), group 2 received the same after fasting for 24 h, group 3 received the dose divided into two halves at 6 h intervals, group 4 received a double dose of ALB, and group 5 received the recommended dose of ivermectin (IVM). Group 6 served as a control. The second phase of the experiment had two groups: one treated with levamisole (LEV) and a control group. Faecal samples were collected from all sheep. Results: No reduction of egg output was observed in the groups treated with single, double, or divided doses of ALB, but one of 13.7–16.9% was noted in the fasting group. Efficacy in the IVM group ranged from 31.50 to 39.97%. The mean concentrations sufficient to prevent 50% of the eggs from hatching in the in vitro EHT and the mean concentrations in which the development of larvae to the L3 stage was inhibited by 50% in the LDT exceeded established thresholds for benzimidazoles and IVM. Haemonchus contortus was the only species identified after treatment. The LDT did not indicate the presence of resistance to LEV. All animals treated with LEV were negative for eggs 10 d after treatment. Conclusion: Resistance to ALB and IVM in Haemonchus contortus was confirmed. Alternative approaches to improve the efficacies of benzimidazole did not sufficiently increase the efficacy, but LEV was an efficient anthelmintic treatment. | sheep, drug resistance, alternative treatment, Haemonchus contortus, levamisole | 200 | 575-581 | 4

Strains of Leptospira interrogans belonging to two very closely related serovars, Icterohaemorrhagiae and Copenhageni, have been associated with disease in mammalian species and are the most frequently reported agents of human leptospirosis. They are considered the most pathogenic serovars and represent more than half of the leptospires encountered in severe human infections.

Introduction: Strains of Leptospira interrogans belonging to two very closely related serovars, Icterohaemorrhagiae andCopenhageni, have been associated with disease in mammalian species and are the most frequently reported agents of humanleptospirosis. They are considered the most pathogenic serovars and represent more than half of the leptospires encountered insevere human infections. Material and Methods: Nineteen such isolates from the United Kingdom – human, domestic andwildlife species – were typed using three monoclonal antibodies (F12 C3, F70 C14 and F70 C24) in an attempt to elucidate theirepidemiology. They were further examined by restriction endonuclease analysis (REA), multiple-locus variable-number tandemrepeat analysis (MLVA) and lic12008 gene sequence analysis. Results: Monoclonal antibody F12 C3, which is highly specificfor Icterohaemorrhagiae and Copenhageni, confirmed that all the strains belonged to these two serovars. Sixteen strains wereidentified as Copenhageni and three as Icterohaemorrhagiae serovar. Only one restriction pattern type was identified, thusconfirming that REA is not able to discriminate between the Icterohaemorrhagiae and Copenhageni serovars. Variable-numbertandem-repeat analysis found three loci with differences in the repeat number, indicating genetic diversity between Britishisolates. Sequences of the lic12008 gene showed that all isolates identified as the Icterohaemorrhagiae serotype have a singlebase insertion, in contrast to the same sequences of the Copenhageni serotype. Conclusion: Copenhageni is the predominantserovar in the Icterohaemorrhagiae serogroup isolated in British Isles. There is a genetic diversity of MLVA patterns of theisolates but no genetic tool used in the study was able to determine serovars. | Leptospira, leptospirosis, Icterohaemorrhagiae, Copenhageni, animal pathogens | 200 | 529-536 | 4