Field study to investigate the effectiveness and safety of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) against natural intestinal nematode infections in dogs presented as veterinary patients in Europe

Background A randomised, blinded, positive controlled, multicentre, Good Clinical Practice-compliant, pivotal field study was conducted to evaluate the effectiveness and safety of a new combination of lotilaner + milbemycin oxime tablets (Credelio® Plus; Elanco Animal Health) administered orally to client-owned dogs naturally infected with intestinal nematodes. Methods Client-owned dogs presenting to veterinary clinics from households in France, Hungary and Germany were screened for intestinal nematodes. Dogs with an initial positive faecal egg count that was subsequently confirmed with a follow-up faecal examination to demonstrate the presence of naturally occurring mixed or mono-infections with Toxocara canis, Toxascaris leonina, Trichuris vulpis or Ancylostoma caninum were enrolled on Day 0 into the study. Households were randomised in an approximately 2:1 ratio to receive either an investigational product (IP; Credelio Plus tablets) or control product (CP; Nexgard Spectra® tablets) as treatment. Dogs were administered the IP (n = 278) or CP (n = 117) once on Day 0 at a dose rate of 0.75–1.56 mg/kg bodyweight milbemycin oxime and 20.0–41.5 mg/kg bodyweight lotilaner (IP) or as recommended (CP). Effectiveness of the IP and CP treatments was based on the post-treatment reduction in geometric mean faecal egg counts on Day 8 (range Day 7–10) after treatment as compared to their pre-treatment nematode faecal egg counts. Results Geometric mean (GM) faecal egg counts for T. canis, A caninum and T. vulpis were reduced by ≥ 97.2% in the Credelio Plus group and by ≥ 95.3% in the afoxolaner + milbemycin oxime group. There were insufficient data to calculate a percentage reduction in GM faecal egg counts between Day 0 and Day 8 for T. leonina due to low prevalence. Credelio Plus was well tolerated in this field study. Of the 355 total doses administered, 82.3% were accepted free choice in the IP group compared to 80.8% in the CP group. Conclusions This study demonstrated effectiveness (≥ 97.2% reduction), safety and tablet acceptance of a combination of milbemycin oxime and lotilaner (Credelio Plus) administered orally to dogs with natural intestinal infections of T. canis, A. caninum and T. vulpis.

Prevalence and Faecal Egg Counts of Gastrointestinal Parasites of Merino Sheep in Lesotho

The present study aimed to evaluate the effect of the agroecological zone, host age, and gender on the prevalence and faecal egg load of gastrointestinal parasites (GIPs) for six months (July to December) in the Maseru and Quthing districts, Lesotho. A total of 1919 faecal samples were examined using the McMaster technique. The data were analyzed through generalized estimating equations (GEE) under the binary logistic regression model to determine the significant differences for the GIPs prevalence. Moreover, faecal egg counts (FEC) data were analyzed for repeated measures using GEE. In total, three types of GIPs, namely nematodes, coccidia, and cestodes were identified in this study. The overall prevalence rates of nematodes, coccidia, and cestodes were 53.9%, 46.5%, and 4.3% in the Maseru district, respectively. Furthermore, the Quthing district indicated the prevalence rates of 65.0%, 38.2%, and 0.9% for nematodes, coccidia, and cestodes, respectively. In the Maseru district, the overall faecal egg counts for nematodes, coccidia, and cestodes were within the ranges of 0-20.3, 0-90, and 0-600 eggs per gram, respectively. Additionally, the faecal egg counts in the Quthing district ranged from 0 to 8.000, 6.700, and 2.000 eggs per gram for nematodes, coccidia, and cestodes, respectively. The majority of the Merino sheep (>69%) in both districts had lower faecal egg counts (100-800) per gram. The agroecological zone affected the nematode infestation in both districts. Coccidia in the Quthing was higher in the mountain areas. In the Maseru district, the nematode infestation was not age-dependent; however, in the Quthing district, the prevalence was higher in juveniles, compared to adults. Age and gender did not affect the prevalence and faecal egg counts of nematodes and coccidia. The coccidian faecal egg loads were higher in females, compared to males. Merino sheep in Lesotho are mostly infected with gastrointestinal nematodes and protozoal coccidia, which could have a tremendous impact on their health and productivity. It is, therefore, of significant importance to develop the deworming strategy for sheep of different age and gender groups in different agroecological zones.

Effects of housing systems on behavioural assessment, bone morphometry and faecal egg counts of broiler chickens

Animals that are well-managed thrive and produce better than those kept under conditions which do not take full consideration of their behavioural and welfare needs. This experiment was conducted with one hundred and eighty unsexed one day-old Marshall and Arbor Acre breeds of broiler chickens to investigate the effects of housing systems on behavioural assessment, bone morphometry and faecal egg counts. The birds were brooded for three weeks and acclimatized for one week in their respective housing systems. Each of the housing systems (deep litter and outdoor run) was allotted 90 birds with 45 chicks per breed in three replicates of 15 birds each after balancing for body weights. The birds were fed same quality and quantity of feed and water ad libitum throughout the period of the experiment which lasted for four weeks. Data were collected on behavioural observations, bone morphometry and faecal samples were analyzed to determine the helminthes egg per gram. The experiment was arranged in a 2 x 2 factorial layout in a completely randomized design. The results of behavioural assessment showed that the two breeds of broiler chickens expressed more (p<0.05) of their natural instincts in the outdoor run compared with their counterparts on deep litter housing system. Irrespective of breeds, birds reared on outdoor run had higher (p<0.05) bone strength (14.61N/mm2) compared with those on deep litter (10.68N/mm 2). Also, the result of faecal egg counts showed that broiler chickens reared on deep litter had a higher incidence of intestinal helminthes compared with those managed on outdoor run. It was concluded that outdoor run could be adopted to enhance more expression of natural behaviours, better bone strength and reduced incidence of intestinal helminthes in Marshall and Arbor Acre breeds of broiler chickens.

159 The effect of multispecies swards on parasite faecal egg counts of grazing lambs

Multispecies swards (MSS) for ruminants are increasing in popularity in temperate regions. The objective of this study was to evaluate the effect of MSS containing grasses, legumes and herbs on lambs faecal egg counts (FEC) compared to a perennial ryegrass monoculture. Over two years (2015 and 2016) lambs (n = 60 per year, n = 120 in total per treatment) grazed one of four sward types. The treatments were: perennial ryegrass only (PRG), perennial grass and white clover (PRGWC), six species sward (perennial ryegrass, timothy, plantain, chicory, white and red clover; 6S) and nine species (9S) additional to the 6S were cocksfoot, greater birdsfoot trefoil and yarrow. Feces samples were collected fortnightly commencing when lambs were six weeks old and FEC were determined by the modified McMaster procedure for quantifying Nematodirus and Trichostrongylus eggs. All lambs were treated with anthelmintic at 12 weeks of age and subsequent anthelmintic treatments were administered when a threshold of 400 egg per gram (epg) was reached. The statistical analysis used was a repeated measures model in PROC MIXED of SAS. Nematodirus FEC did not differ with treatment (P &gt; 0.05). Trichostrongylus FEC was influenced by sward type (P &lt; 0.05), the lambs grazing the PRG sward displaying higher FEC, while the lambs grazing the 9S sward displaying lower FEC compared to other treatments. The lambs offered PRG required fewer days in reach the 400 epg threshold compared to the other treatments (P &lt; 0.05) that did not differ. The repeatability of FEC from one date to the next date was 21.54% and 11.85% for Nematodirus and Trichostrongylus respectively, being considered low. The correlation between FEC (Nematodirus) and ADG (weaning-slaughter) was positive (0.1377), but FEC (Trichostrongylus) and ADG correlation was negative (-0.1084). These results suggest that lambs offered the 9S treatment had lower FEC of Trichostrongylus eggs compared to PRG.

Anthelmintic Potency of Neem (Azadirachta indica) Leaf Meal on West African Dwarf (WAD) Sheep

A 90-day study was conducted to determine the response of semi intensively managed West African dwarf sheep to concentrate supplement containing varying levels of neem leaf meal (NLM). Twenty (20) West African Dwarf sheep aged 5 to 6 months with an average weight of 10kg were used in a Completely Randomized Design with animals grouped into four treatments of five replicates each balanced for weight. The animals were allowed to graze on natural pastures predominantly made up of Panicum maximum in the morning with a daily supplementation of 100g concentrate diet containing varying levels of neem leaf meal at 0, 5, 10 and 15%. Blood samples were taken from the animals before the commencement of the experiment and at the end of the experiment. At the start of the experiment, faecal samples were collected from each animal to determine the faecal egg count and this was repeated once in three weeks for the 90 day experimental period. There was significant (P < 0.05) difference in the haematology indices studied with no definate pattern. The inclusion of NLM in the diets of West African Dwarf sheep significantly (P < 0.05) reduced the faecal egg counts across the treatments with a percentage reduction range of 33.38 to 88.00% for sheep on 0% and 5% NLM, respectively. This study, however, concluded that neem leaf inclusion at 5% in West African dwarf sheep’s diet had effects on the overall performance of the animals with a potential improvement in drastic reduction in faecal egg counts.