In the present multidisciplinary study, the researchers on a field trial performed a Social Network approach and a group of 9 calves (3 males/6 females) aged 10 to 16 weeks. A 24 hours digital camera was used for location registration (X-Y position) and interactions on each calf, both individually and collectively. Based on the simple methodology nearest neighbor matrix positive and negative associations were analyzed. The field study lasted 4 weeks and the maximum interaction day was chosen, when individual calf activity was high. To those of 9 calves solely no 2 was infected with giardiasis on the first week, whereas calves with no:2, 7, and 8 were also infected on the second week. No: 4 and 6 were also infected with a total of 5 calves on the third week. This was followed by the final 6 calves in total infected. During the observation period, both by investigators and camera records, infected calf 2 was in close contact with no: 8 (at morning observation) and a slight degree of contact with no: 3 and 4 which were detected with giardiasis on the third and fourt weeks, respectively. Due to close contact with no: 8, infection was determined on the second week, earlier than others (except no: 7). Calves with no: 1 and 5 were never infected nor determined by PCR, fecal smear, or rapid diagnostic test kits throughout the study. In conclusion, the present authors suggested that social networking might be an important predisposing factor for giardiasis infection among calves.

Two commercially available tests, an antigen-capture ELISA for use on fecal samples, and a peroral nylon string test for use in dogs, were compared with a zinc sulfate fecal concentration technique (ZSCT) for detection of giardiasis in dogs. Of 77 dogs and 164 fecal samples (from these dogs), 33 and 52, respectively were found to be Giardia-positive on the basis of results of the ZSCT. The ELISA gave false-negative results for 10 and 14% of ZSCT-positive dogs and fecal samples, respectively, and false-positive results (relative to the ZSCT test results) in 13 and 10% of ZSCT-positive dogs and fecal samples, respectively. Of the 18 string-tested dogs, 14 were positive by results of the ZSCT. Of the 4 dogs that were Giardia-negative by ZSCT, 2 were Giardia-positive by ELISA. Dogs were sedated and given water and metoclopramide to aid passage into the duodenum of the capsule containing a nylon string. Of the 21 string tests performed on the 18 dogs, only 5 strings reached the duodenum, and 0 of the 5 yielded positive results for Giardia sp. Because the string broke in 1 dog (leaving most in the gastrointestinal tract and, therefore, producing a risk of string foreign body) further string tests were not done.

The present study was conducted to assess the prevalence of Giardia species infection in cattle and human. One hundred of animal fecal samples and 139 human stool samples were collected from different veterinary clinics and its related hospitals respectively. All samples were undergone to microscopically examination by; direct smears in 0.90% Na Cl solution, Lugol's iodine stain for cyst detection and formol-ether concentration. 9 (28.1%) calves from 32 were positive in microscopic examination by the used techniques. 25% of the examined fecal samples of cattle (17/68) were containing cysts of Giardia species by microscope. 39 of 139 (28.1%) of human stool samples were found infected by this protozoon. Regarding the sex of human cases, 26.30% of examined males were positive while 30.20% of females were positive. The age factor in human infection was clear; the age group of 11 to 20 years were the more infected than the other group (1- 10ys). There is no relation between form of human stool and infection rate. ELISA kits confirmed that 6 % of animal cases and 15.8% of human were positive. The epidemiological aspects were discussed in the study.

Objective: To examine the effects of giardiasis on production and carcass quality, using growing lambs as a domestic ruminant model. Design: Randomized block. Animals: Giardia-free lambs: 23 in infected group, 24 in control group. Procedure: Six-week-old, specific-pathogen-free lambs were infected with Giardia trophozoites; control lambs received saline solution. Clinical signs of infection, body weight, and feed intake were determined for 10 weeks. Carcass weight and quality were determined at slaughter weight of 45 kg. Results: Giardia infection persisted from weeks 7 to 16. For 5 weeks after challenge exposure, abnormal feces were more frequently observed in infected lambs. Giardia infection was associated with a decrease in rate of weight gain and impairment in feed efficiency. Time to reach slaughter weight was extended in infected lambs, and the carcass weight of Giardia-infected lambs was lower than that of control lambs. Conclusion: Giardiasis has a negative effect on domestic ruminant production. Clinical Relevance: Giardiasis in domestic ruminants is an economically important disease, thus necessitating control or elimination of the infection.

Efficacy of fenbendazole at 2 dosages for treating naturally acquired giardiasis in dogs was assessed. Giardia cysts were not detected in the feces of 6 of 6 group-1 dogs (as determined by use of the zinc sulfate concentration technique) after fenbendazole treatment (50 mg/kg of body weight, PO, q 24 h, for 3 doses). Cysts were not detected in the feces of 6 of 6 group-2 dogs after fenbendazole treatment (50 mg/ kg of body weight, PO, q 8 h, for 3 days). However, cysts were not detected in the feces of only 1 of 6 group-3 (nontreated control) dogs. Signs of toxicosis were not observed in any dog. These results indicate that the current label dosage (for the treatment of Toxocara canis, Toxascaris leonina, Ancylostoma caninum, Uncinaria stenocephala, Trichuris vulpis, and Taenia pisiformis, but not Giardia spp) of fenbendazole (50 mg/kg, PO, q 24 h, for 3 doses) is also effective for treating giardiasis in dogs.

Efficacy of albendazole for treating giardiasis in dogs was assessed in 3 experiments. In experiment 1, Giardia cysts were cleared from feces of 5 of 7 dogs (as determined by the zinc-sulfate concentration technique) after the dogs received a single dose of albendazole (25 mg/kg of body weight, PO), whereas feces of 3 of 7 dogs became clear of cysts without treatment. In experiment 2, feces of 5 of 5 dogs became clear of cysts after albendazole treatment (25 mg/kg, PO, q 12 h for 4 doses); feces of 1 of 5 untreated control dogs became clear. In experiment 3, feces of 18 of 20 dogs became clear of cysts after albendazole 25 mg/kg, PO, q 12 h for 4 doses) was given; none of the 20 control dogs had feces clear of cysts. Signs of toxicosis were not observed in any dog. These results indicate that a single dose of albendazole (25 mg/kg, PO) is not effective for treating giardiasis in dogs. However, 4 doses of albendazole (25 mg/kg, PO, q 12 h) are highly effective and nontoxic for treatment of giardiasis in dogs.