Field efficacy of eprinomectin against the sucking louse Haematopinus asini on naturally infested donkeys

Horse and donkey parasitology: differences and analogies for a correct diagnostic and management of major helminth infections

In June 2022, at the XXXII Conference of the Italian Society of Parasitology, the parallels of the main endoparasitic infections of horses and donkeys were discussed. Although these 2 species are genetically different, they can be challenged by a similar range of parasites (i.e. small and large strongyles, and Parascaris spp.). Although equids can demonstrate some level of resilience to parasites, they have quite distinct helminth biodiversity, distribution and intensity among different geographical locations and breeds. Heavily infected donkeys may show fewer clinical signs than horses. Although parasite control is primarily provided to horses, we consider that there may be a risk of drug-resistance parasitic infection through passive infection in donkeys when sharing the same pasture areas. Knowing the possible lack of drug efficacy (<90 or 80%), it is advocated the use of selective treatment for both species based on fecal egg counts. Adult horses should receive treatment when the threshold exceeds 200–500 eggs per gram (EPG) of small strongyles. Moreover, considering that there are no precise indications in donkeys, a value >300 EPG may be a safe recommendation. We have highlighted the main points of the discussion including the dynamics of helminth infections between the 2 species.

Clinical Pharmacology in Donkeys and Mules

Donkeys and mules show several pharmacodynamic and pharmacokinetic idiosyncrasies that have to be fully considered by any clinician dealing with these species. Because they possess an increased metabolic rate and cellular water content compared with horses, higher doses (or shorter dosing intervals) are usually recommended for those drugs where pharmacologic studies have been performed. Nonetheless, owing to the lack of species-specific information, this assumption cannot be arbitrarily applied. Thus, when a drug protocol published for horses is extrapolated to a donkey or a mule, a close monitoring is required to detect any secondary effect or subdosing.

Evaluation of Two Handheld Point-of-Care Blood Gas Analyzers in Healthy Donkeys

There has been increasing interest in blood gas analysis in donkeys. "Point-of-care (POC) testing" is a diagnostic testing performed on or immediately next to the patient. This study assesses the agreement between two POC blood gas analyzers in donkeys. Arterial and venous blood samples were collected from 17 donkeys and analyzed using a fully automated blood gas analyzer (ABL 700 Series Radiometer, Denmark) (RAD) and two POC blood gas analyzers (i-STAT System; VetStat, Idexx). The parameters revealed by all three devices were submitted to a canonical discriminant analysis, to evaluate which parameters differentiated the POC analyzers from the RAD. On the basis of the discriminant analysis, we evaluated the best POC for each parameter registered, in comparison with RAD. The results also changed depending on the type of blood (venous or arterial blood). The agreement between i-STAT and RAD was good for venous samples, but was poor for arterial samples. A poor agreement was found between VetStat and RAD for both venous and arterial samples. The increment of the number of subjects might lead to a better understanding of the potential role of the POCs in clinical setting. Finally, increasing the study population is recommended to set reference values.

Selenium and Vitamin E Concentrations in a Healthy Donkey Population in Central Italy

Selenium and vitamin E protect the body against oxidative stress. Clinical manifestations of their deficiency in equids include neurologic and muscular symptoms. Despite the importance of donkeys as working and production animals, there is a dearth of scientific data on selenium and vitamin E normal values. Therefore, the aim of this study was to investigate the plasma concentrations of selenium and vitamin E in healthy donkeys belonging to different ages, sexes, and productive phases. Animals were divided into five groups including foals (group A: n = 7, n = 4 males and n = 3 females), weanlings and yearlings (group B: n = 7, n = 2 males and n = 5 females), nonpregnant nonlactating jennies (group C: n = 5), pregnant nonlactating jennies (group D: n = 9), and adult males (group E: n = 9). Plasma samples obtained from each animal were tested for vitamin E and selenium concentration. One-way analysis of variance showed significant differences in selenium concentrations (P = .001) between group A and group E. In this study, we found the selenium range for donkeys to be 0.02-0.14 μg/mL, which is lower than the recommended range for horses. The results suggest that donkeys may have a lower selenium requirement than horses. Plasma vitamin E levels were 3.29-12.99 μmol/L, with foals having lower concentrations than adults. Knowing specific reference ranges for vitamin E and selenium in healthy donkeys can help improve our understanding of how to prevent deficiencies that could compromise their overall health and well-being.