Ian Beveridge’s research while affiliated with Victoria University and other places

Gastrointestinal nematodes (GINs) pose major health, production and welfare concerns for the global goat industry, resulting in significant economic losses. Our understanding of the prevalence and intensity of GINs in Australian dairy goats is limited. This study aimed to determine the prevalence and intensity of GINs in Australian dairy goats. Between November 2023 and July 2024, 1,028 individual faecal samples collected from 68 dairy goat farms across six states/territories were analysed using the modified McMaster technique for faecal egg counts (FECs), with eggs per gram (EPG) determined for strongyles, Trichuris and Nematodirus. All goats had not received anthelmintic treatment for at least eight weeks prior to sampling. The overall prevalence of GINs was 91% (931/1,028), with the highest prevalence for strongyles (88%; 905/1,028) followed by Trichuris (14%; 142/1,028) and Nematodirus (7%; 75/1,028). Similarly, the highest intensity was observed for strongyles (mean EPG = 1,085; range 0-16,710) followed by Trichuris (16.0; 0-1,440) and Nematodirus (6.0; 0-510). Based on strongyles FECs, adult goats had the highest prevalence (93%; 656/708) followed by weaners (85%; 115/135) and kids (71.7%; 132/184). Additionally, the mean EPG of strongyles was higher in adults (1,238) than in weaners (803) and kids (706), with approximately 30% of goats responsible for 80% of total FEC outputs. Based on larval culture, preliminary results revealed that Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus spp. were the main GINs infecting Australian dairy goats. The findings from this study indicate that GINs are a widespread issue for dairy goat producers, and infection levels exist at magnitudes that suggest potential production losses, thereby requiring national efforts to achieve sustainable control of GINs in the wake of widespread antiparasitic drug resistance.

This study assessed gastrointestinal (GI) parasite control practices used by Australian dairy goat farmers through an online questionnaire survey. The questionnaire consisted of 54 questions on farm demographics, husbandry and grazing management, knowledge of GI parasites and their significance, diagnosis, anthelmintics, and alternative control options. After a pilot survey, the questionnaire link was sent to all registered members (n = 456) of the Dairy Goat Society of Australia Ltd on 17th April 2023. The response rate was 14% (66/456). Most respondents owned medium-sized herds (20-100 goats; 56%, 37/66) followed by small (<20 goats; 36%) and large (>100 goats; 8%) herds. Seventy-four percent (49/66) of respondents observed parasite-related illnesses in their goats and two-thirds assessed worm burden using faecal egg counts. Most respondents (97%; 183/188) perceived that GI parasites caused production losses or health impacts and ranked Haemonchus contortus as the most significant parasite. Ninety-four percent (62/66) of respondents used anthelmintics, primarily a commercial combination of four anthelmintics (levamisole, closantel, albendazole, and abamectin), benzimidazoles and macrocyclic lactones. Although targeted deworming was the most common method of controlling GI parasites, most respondents were unaware of anthelmintic resistance. These findings will pave the way to devise guidelines for GI parasite control in goats.

Gastrointestinal helminths were collected from pademelons of the genus Thylogale (Marsupialia: Macropodidae) in eastern Australia and Papua New Guinea. Examined were 12 Thylogale stigmatica stigmatica and 13 T. s. wilcoxi, the latter subdivided into eight specimens from the northern limit of their distribution and five from southern areas, all from eastern Queensland, Australia, one T. s. oriomo from Papua New Guinea and ten T. thetis from southeastern Queensland and northern New South Wales, Australia. Six species of cestodes and 40 species of nematodes were found. The helminth community of T. s. stigmatica was similar to that found in northern specimens of T. s. wilcoxi, while differences from the helminth community present in southern T. s. wilcoxi could be accounted for by parasites acquired from sympatric T. thetis. Thylogale thetis harboured a community of helminths distinct from but related to that in T. stigmatica. The evidence suggests that all subspecies of T. stigmatica examined share a common helminth community, but that in areas of sympatry, T. stigmatica and T. thetis share some of their parasites.

This study assessed worm control practices used by Australian Thoroughbred farm managers with an online questionnaire survey. The questionnaire comprised 52 questions (close-ended: 44; open-ended: 8) about farm demography and general husbandry practices, farm managers’ knowledge of gastrointestinal nematodes (GIN) and their importance, diagnosis, worm control strategies and anthelmintics, anthelmintic resistance (AR) and grazing management. Following the pilot survey, the link for the questionnaire survey was sent to all (n = 657) registered members of the Thoroughbred Breeders Australia on 12th April 2020. The response rate for the questionnaire was 18.5% (122 of 675). The farm managers reported a good understanding of GIN and their importance in different age groups of horses as most respondents (70% of 122) perceived worm-related illness to be more important in young (i.e., foals, weanlings and yearlings) than adult (> 3 years old) horses. Although most respondents (93%, 113 of 122) used anthelmintics prophylactically to control GIN, only 15% (18 of 122) observed worm-related illness in their horses. Just under 40% of respondents were performing faecal egg counts, with less than 20% using the results of faecal egg counts to guide deworming decisions. The interval-based deworming strategy was the most common method (≥55% of 122 respondents) to control GIN in all age groups of horses. Macrocyclic lactones were the first choice of anthelmintics for all age groups of horses. Although the majority of respondents (88%, 107 of 122) perceived resistance in GIN against commonly used anthelmintics as an important issue in managing worms in horses, only 29% assessed the efficacy of anthelmintics and 91% (111 of 122) were unaware of AR on their properties. Grazing management practices, such as manure removal, were more frequently performed on smaller paddocks (<0.20 ha: 58%) than on larger paddocks (>0.20 ha: 18%). Multiple correspondence analyses showed that the likelihood of suboptimal worm control practices on small farms (n = ≤50 horses) was greater than that of medium (n = 51–100) and large (n = >100) farms. This study provides insights into the demography of Thoroughbred farms in Australia, husbandry practices used by stud managers and their knowledge about worms, control options and AR concerns, thereby paving the way for taking any initiatives to address the problem of AR in GIN of Australian Thoroughbred horses.

The helminth parasites of Macropus fuliginosus and Macropus giganteus are reported based on examination of a total of 285 animals extending, for the first time, across the entire geographical range of both species and including, where possible, data from previous regional studies. A total of 64 species of helminths was found including 42 species of strongyloid nematodes in the stomach, seven species of trichostrongyloid nematodes in the pylorus and small intestine and seven species of nematodes in the terminal ileum and large intestine, one species of spirurid nematode in the stomach and six species of cestodes and one species of trematode. Forty-three species were encountered in both M. fuliginosus and M. giganteus. The helminth communities of the two kangaroo species exhibited a similarity of 85.4% based on all helminth species encountered or 91.4% if only the species specific to grey kangaroos were considered. Interchange of helminths between the two species of kangaroos revealed several different patterns with instances both of transfer and lack of transfer in areas of host sympatry as well as transfers beyond the zone of sympatry. The findings are discussed in relationship to the phylogeography of the host species.