Gastrointestinal parasites of dogs and foxes in the Zanjan province of Iran: With an emphasis on Echinococcus species

Canids harbor many zoonotic parasites and play an important role in the spread of parasites in the human environment. Estimation of parasitic infection among canids as definitive hosts may help competent authorities design efficient control programs. This study was conducted to determine the prevalence of intestinal parasites in dogs and foxes with an emphasis on Echinococcus spp. A total of 500 fecal samples of dogs and 30 fecal samples of foxes were studied in the summer, autumn, and winter of 2021 in the Zanjan province using the formalin-ethyl acetate concentration technique, followed by multiplex PCR. The overall prevalence of gastrointestinal parasite infection was estimated to be 19.05%. The prevalence was 24.8%, 10.2%, and 26.7% in stray, shelter dogs and foxes, respectively. No parasites were found among pet and guard dog samples. PCR results on Taenidae eggs showed that 2.4% of samples were positive for Echinococcus granulosus and none contained E. multilocularis. Noteworthy is that E. granulosus was identified only in stray dog samples. The higher prevalence of E. granulosus infection in stray dogs in this province emphasizes the importance of monitoring the food sources consumed by these animals.

Dairy cattle and buffaloes harbouring gastrointestinal parasites in various zones and climatic regions established by scientometrics

The prevalence of gastrointestinal parasites (GIP) in cattle and buffaloes from different zones and climatic regions in India was determined by scientometrics. The GIP prevalence studies (64) described during 2004-2021 were retrieved from online databases, and offline literature and meta-analyses were conducted by meta package in R-Software. The GIP prevalence in India was 47% (95% level CI 41-54%, PI 12-85%) in cattle, 42% (95% level CI 35-50%, PI 9-84%) in buffaloes and 45% (95% level CI 40-51%, PI 12-84%) in cattle and buffaloes obtained from 40,884, 27,624 and 74,579 samples, respectively. The GIP prevalence was higher in the South zone (60%) for cattle, North zone (52%) for both buffaloes, and cattle and buffaloes. A higher GIP prevalence was observed in Tamil Nadu for cattle, Chhattisgarh and Tamil Nadu for buffaloes, and Karnataka for cattle and buffaloes. Prevalence of Ostertagia spp. in cattle, Buxtonella spp. in buffaloes, and Haemonchus spp. in cattle and buffaloes were higher among parasitic species. The polar and Semi-Arid Steppe climatic region harbours more GIP than other regions. Thus, the higher prevalence zones, states, sample types, parasite classes, parasitic species, and climatic regions identified in the present study may be used by policymakers for making informed decisions and effectively using scarce resources. However, there is a need to prevent GIP infections by implementing scientific managemental practices in dairy farms, rotational use of anthelmintic drugs, appropriate control, and preventive measures, which will result in beneficial dairy farming in India.

Gastrointestinal parasites of endemic and endangered free-ranging purple-faced leaf monkey (Semnopithecus vetulus) in Sri Lanka: effect of host group size and habitat type

Similar infectious agents may be shared among human and nonhuman primates due to their close proximity. Gastrointestinal parasitism is one of the main diseases which can be transmitted between human and nonhuman primates. It is vital to understand the potential transmissions of gastrointestinal parasites (GIP) and monitor their prevalence in free-ranging populations. This study was carried out to determine the prevalence and diversity of the GIP of Semnopithecus vetulus in Sri Lanka from December 2017 to April 2019. Fresh fecal samples (N = 78) were collected and analyzed using fecal floatation technique and direct iodine mounts. Of these, 55% contained at least one species of GIP (helminths: N = 18 protozoans: N = 30). Multiple infections were recorded in 12% of the samples testing positive for parasites. The most prevalent helminth was Trichuris trichiura (15%). A significant relationship was found between the prevalence of T. trichiura and troop size. There were also significant differences in the prevalence of T. trichiura and Ascaris lumbricoides with habitat type. Compared to the forest dwelling populations sampled, those dwelling in urban and suburban habitats receive higher solar radiation, daytime temperatures and disturbance from humans. These conditions can be expected to influence GIP infection rates. S. vetulus living in continuously degrading habitats face a significant threat from GIP infections. Continuous and improved parasitological surveillance is needed to help monitor the conservation status of wildlife and to secure human health.

Ascorbic acid potentiates the Giardia duodenalis growth inhibitory activity of pure Terminalia ferdinandiana Exell compounds

Giardiasis, one of the most common causes of diarrhoeal disease, is caused by gastrointestinal protozoal parasites of the genus Giardia. Metronidazole is the most commonly used drug to treat giardiasis. However, metronidazole resistance is increasingly common, making the development of new anti-giardial drugs a high priority. A panel of 11 compounds previously identified in T. ferdinandiana fruit extracts were investigated for the ability to inhibit G. duodenalis proliferation. Eight of the 11 compounds inhibited the growth of all three G. duodenalis strains. 2,3-Dihydroxyphenyl B-D-glucopyranosiduronic acid (DPGA) was the most potent anti-giardial compound, with IC₅₀ values as low as 126 μM (38 μg/mL). Notably, DPGA inhibited a metronidazole-resistant G. duodenalis strain with similar activity as determined for the metronidazole-sensitive strains. Furthermore, the activity of DPGA was greatly potentiated when it was tested in combination with ascorbic acid, to approximately 17 μM (5 μg/mL) for the metronidazole-sensitive G. duodenalis strains and 40 μM (12 mg/mL) for the resistant strain. The T. ferdinandiana tannins (gallic acid and chebulic acid) were moderate inhibitors of G. duodenalis growth when tested in combination with ascorbic acid, although they had only low levels of activity when tested alone. All of the tested compounds (and their combinations with ascorbic acid) displayed low toxic effects and all compounds are conformed to Lipinski's rules of 5 with few violations, indicating their potential as drug leads and chemotherapies for the treatment and prevention of giardiasis.

Prevalence of gastrointestinal parasites in free-range yaks (Bos grunniens) in Gansu Province, Northwest China

BACKGROUND

Little information about the prevalence of gastrointestinal parasites in yaks (Bos grunniens) in northwest China is available. Therefore, the objective of the study was to quantify faecal egg counts of gastrointestinal parasites (helminths and coccidia) in free-range yaks from Gannan Tibetan Autonomous Prefecture, Gansu Province, Northwest China.

RESULTS

Parasites were detected in 290 of 733 (39.56%) faecal samples. The results showed that Strongylidae, Trichuris spp. and Eimeria spp. were detected all year round, Strongyloides papillosus was detected in autumn and summer, and Nematodirus spp. was detected in both autumn and spring. In contrast, Fasciola spp. was only detected in spring. The prevalence rates of parasitic infections in different seasons were significantly different.

CONCLUSIONS

To our knowledge, this is the first investigation of gastrointestinal parasites in yaks (Bos grunniens) in Gansu, China. The results demonstrated a high prevalence of gastrointestinal parasitic infections, specifically GN infections, in yaks in GTAP and these infections can cause economic losses to the local cattle industry.

Self-selection of plant bioactive compounds by sheep in response to challenge infection with Haemonchus contortus

Plant bioactives can potentially benefit herbivores through their effects on health and nutrition. The objective of this study was to determine the importance of polyphenols and terpenes on the ability of lambs to self-select these compounds when challenged by a parasitic infection and the subsequent impact on their health and productivity. Thirty-five lambs were housed in individual pens and assigned to five treatment groups (7 animals/group), where they received: 1) A basal diet of beet pulp:soybean meal (90:10) (CONTROL); 2) The same diet, but containing 0.3% of bioactive natural plant compounds extracted from grape, olive and pomegranate (BNP); 3) A simultaneous offer of the diets offered to the Control and BNP groups (Choice-Parasitized; CHP-1); 4) The Control diet, and when lambs developed a parasitic infection, the choice described for CHP-1 (CHP-2); and 5) The same choice as CHP-1, but animals did not experience a parasitic burden (Choice-Non-Parasitized; CHNP). Lambs, except CHNP, were dosed with 10,000 L₃ stage larvae of Haemonchus contortus. Infected lambs under choice treatments (CHP-1 and CHP-2) modified their feeding behavior in relation to the CHNP group as they increased their preference for the feed containing polyphenols and terpenes, interpreted as a behavior aimed at increasing the likelihood of encountering medicinal compounds and nutrients in the environment that restore health. This change in behavior corresponded with an improvement in feed conversion efficiency. However, an increased preference for the diet with added plant bioactives did not have an effect on parasitic burdens, hematological parameters, blood oxidation, or serum concentration of IgE.

Proteomic identification of galectin-11 and 14 ligands from Haemonchus contortus

Haemonchus contortus is the most pathogenic nematode of small ruminants. Infection in sheep and goats results in anaemia that decreases animal productivity and can ultimately cause death. The involvement of ruminant-specific galectin-11 (LGALS-11) and galectin-14 (LGALS-14) has been postulated to play important roles in protective immune responses against parasitic infection; however, their ligands are unknown. In the current study, LGALS-11 and LGALS-14 ligands in H. contortus were identified from larval (L4) and adult parasitic stages extracts using immobilised LGALS-11 and LGALS-14 affinity column chromatography and mass spectrometry. Both LGALS-11 and LGALS-14 bound more putative protein targets in the adult stage of H. contortus (43 proteins) when compared to the larval stage (two proteins). Of the 43 proteins identified in the adult stage, 34 and 35 proteins were bound by LGALS-11 and LGALS-14, respectively, with 26 proteins binding to both galectins. Interestingly, hematophagous stage-specific sperm-coating protein and zinc metalloprotease (M13), which are known vaccine candidates, were identified as putative ligands of both LGALS-11 and LGALS-14. The identification of glycoproteins of H. contortus by LGALS-11 and LGALS-14 provide new insights into host-parasite interactions and the potential for developing new interventions.

Endoparasites in a Norwegian moose (Alces alces) population - Faunal diversity, abundance and body condition

•

Moose in Hedmark have high abomasal parasite burdens.

•

11 parasite groups were identified with abomasal GINs found in all individuals.

•

4 abomasal GINs identified; Ostertagia antipini and Spiculopteragia alcis dominated.

•

Body condition index was negatively related to abomasal parasite burden.

•

Fat reserve assessment and faecal egg count were poor indicators of parasitism.

Many health surveillance programs for wild cervids do not include routine parasite screening despite evidence that gastrointestinal parasites can affect wildlife population dynamics by influencing host fecundity and survival. Slaughter weights of moose in some regions of Norway have been decreasing over recent decades but any role of parasites has not yet been considered. We investigated parasite faunal diversity of moose in Hedmark, SE Norway, by faecal analysis and identification of adult abomasal and caecal nematodes during the autumn hunting season. We related parasite prevalence and abundance to estimates of body condition, gender and age. We identified 11 parasite groups. Moose had high abomasal gastrointestinal nematode (GIN) burdens and all individuals were infected. Ostertagia antipini and Spiculopteragia alcis were the most prevalent abomasal GINs identified. O. leptospicularis and Telodorsagia circumcincta were also identified in the abomasa while a range of other GIN and Moniezia sp. eggs, and coccidia, Dictyocaulus sp. and Protostrongylid larvae were found in faeces.

Female moose had higher mean abomasal nematode counts than males, particularly among adults. However, adult males had higher faecal egg counts than adult females which may reflect reduction in faecal volume with concentration of eggs among males during the rut. We found no strong evidence for the development of acquired immunity to abomasal nematodes with age, although there was a higher Protostrongylid and Moniezia infection prevalence in younger animals. High burdens of several parasites were associated with poor body condition in terms of slaughter weight relative to skeletal size but unrelated to visually evaluated fat reserves. Given findings from earlier experimental studies, our results imply sub-clinical effects of GI parasite infection on host condition. Managers should be aware that autumn faecal egg counts and field assessments of fat reserves may not be reliable indicators of parasitism and may underestimate impacts on wildlife populations.