Prevalence and risk factors for epizootic lymphangitis among equids in ethiopia during 2002-2023: A systematic review and meta-analysis

In Sub-Saharan Africa (SSA), particularly in Ethiopia, Epizootic Lymphangitis (EL) is the most prevalent fungal disease of equids, which causes significant economic losses as well as a decrease in equid populations. Therefore, this systematic review and meta-analysis were designed to pool the results of individual studies and estimate the prevalence of EL among equids in Ethiopia. A systematic search of research articles on the prevalence and risk factors of EL among equids in Ethiopia was conducted in registers, databases, and other sources. Cochrane's Q, inverse variance (I2), sensitivity analysis, funnel plot, Begg's, and Egger's regression tests were used to check heterogeneity and publication bias. A random-effects model was used to calculate the pooled burden of EL among equids. For this meta-analysis, a total of 7217 equids were included in the 14 eligible studies. The overall pooled prevalence of EL among equids in Ethiopia was 20.24% (95% CI: 16.27, 24.21). According to the subgroup analysis, the highest prevalence was observed in cart horses (20.98%), the Amhara region (21.46%), and studies conducted using sample sizes of 384 equids or greater (24.67%) and from 2002 to 2018 (25.52%) study periods. Harness-inflicted wounds, sharing stables or yards with harnesses, and the presence of preexisting wounds were identified as factors significantly associated with EL magnitude. Early diagnosis and proper medication, as well as implementing appropriate prevention and control measures, are necessary for the management of EL in equids.

Morphological Characteristics, Preferences, and Perceptions of the Ideal Working Mule

Suitability and physical attributes of working mules are important features that can affect management, performance, and welfare. The aim of this study was to assess the morphology of working mules used in the Chilean army and determine if they adjust to soldier's preference and perceptions of their ideal pack mule. A total of 16 morphometric traits were measured per mule and six morphofunctional indexes calculated in 60 mules. Perception and preferences for the ideal mule in 73 soldiers was assessed through a questionnaire. The questionnaire included one closed-ended question where the ideal mule size could be selected and one open-ended question about their ideal mule, which was analyzed by text mining. The studied mules were well-balanced, with more riding and saddle type aptitude than for load work. According to responses, the ideal pack mule should be docile, medium size, resistant and suitable for load work in mountainous terrain.

Influence of workload and weather conditions on rolling behaviour of horses and mules

We evaluated the influences of workload intensity, bath handling and environmental conditions in the rolling behaviour of horses and mules. For this purpose, animals were observed after being exposed to different levels of workload and the rolling behaviour was recorded and described. During all testing procedures, the weather condition (temperature and humidity) was registered by a Black globe and Wet Bulb apparatus. Horses frequently rolled after intense exercise and after bath handling, independently of the weather condition. Mules frequently rolled after control (no exercise) and intense exercise in warmer and wetter days and after bath handlings in colder and drier days. Rolling behaviour characteristics were slightly different between species. While mules exhibited more frequently the behaviours of rest, self-care, yawn, tail swishing, complete spins, snort vocalization and use of the same spot to roll, horses exhibited more frequently the behaviours of paw, sniff, head and neck rubbing movements and incomplete spins to the right and left. This findings evidence that rolling is an important and frequently exhibited behaviour by domestic horses and mules, but animals may express it differently and may have their own motivations. In this sense, we believe that domestic equines, mainly those raised in more intensive livestock, should have the opportunities to freely express the rolling, as a way to improve their welfare conditions and with agreement with a more rational handling practice.

Frequency and factors associated of potential zoonotic pathogens (Borrelia spp., Rickettsia spp., Leishmania spp., and Anaplasma phagocytophilum) in equids in the state of Bahia, Brazil

BACKGROUND

Currently, various zoonotic diseases are classified as emerging or reemerging. Because equids have a direct relationship with various vectors, they are possibly more frequently exposed to zoonotic agents than are humans. The undeniable importance of diseases such as human granulocytic anaplasmosis, spotted fever, and leishmaniasis for both public and animal health, as well as the possibility of equids acting as sources, reservoirs, or even sentinels for these pathogens, justifies the detection of their frequency and factors associated with infection in equids from northeastern Brazil.

METHODS

Blood samples were collected from 569 equids (528 horses, 33 donkeys, and 8 mules), 516 from a rural area and 53 from an urban area. Pathogen detection was carried out as follows: Borrelia spp. and Rickettsia spp., serological analysis; Leishmania spp., serological analysis and polymerase chain reaction (PCR); Anaplasma phagocytophilum, PCR. Determination of associated factors was carried out through generalized linear models.

RESULTS

The frequencies of positivity for the pathogens observed in equids were as follows: Borrelia spp., 13.9% (79/569); Leishmania spp., 3.5% (20/569); Rickettsia spp. 33.4% (190/569). Regarding factors associated with infection, male sex was associated with protection against Borrelia spp.; donkeys and mules were associated with protection against Rickettsia spp., while a younger age was a risk factor. The infection of A. phagocytophilum was not detected in the sampled population. Co-infection was detected in 5.1% (29/569) of the animals.

CONCLUSIONS

Most of the studied pathogenic agents are present in the prospected area, indicating a possible risk for both human and animal health. This demonstrates that equids can be considered important sentinels in the assessment of pathogens with zoonotic potential in the region.

Dominance and Leadership in the Equine Social Structure: A Preliminary Study About Mules and Sex Influence

Little is known about the dominance and leadership behaviors in the social structure of mules (Equus caballus × Equus asinus). Based on the frequency of threat and aggressive behaviors, we compared the social structure, dominance, and leadership of independent groups of mules and horses (n = 11 per group), and filmed the frequency of these behaviors over a period of four days. In both groups, aggressions were uncommon and, when based on threats, the social structure was linear and consistent with males ranking higher in dominance. When compared to horses, mules exhibited some agonistic social interactions without a recognized submissive individual and displayed more specific aggressive behaviors, whereas horses presented more specific threat behaviors. Comparing between groups, mares exhibited more leader behaviors than female mules, in contrast to male horses which showed fewer leader behaviors than male mules. Regarding behaviors within the mule group, males showed more leader and threat behaviors than females, while females showed more frequent aggression. While in horses, the females showed more leader behaviors than male horses and, although there were differences in specific agonistic behaviors, both sexes presented more often threat behaviors. In this preliminary study, we conclude that the social structure of mules, although similar to those of horses, showed to be less stable, since it involves more aggression and agonistic social interactions without a submissive. Moreover, although mules did not present a sex influence on leadership as horses did, they presented it on aggression: females showed more aggression than males.

Serum Amyloid A (SAA) Concentration after Vaccination in Horses and Mules

Serum amyloid A (SAA) is a sensitive acute-phase response (APR) marker in equids. Prominent APRs with elevations of SAA concentrations ([SAA]) have been reported after vaccination. The authors hypothesized that vaccination with an inactivated EHV-1/-4 vaccine would cause increase in [SAA] and antibody responses and that higher [SAA] would be positively correlated with the antibody titer in both equids. Twelve Haflinger horses and 12 mules were included in this longitudinal prospective study. All horses and mules were vaccinated with a commercially available EHV-1/-4 vaccine. Blood was sampled before and after vaccination to measure [SAA] and virus-neutralizing response (VN-T). In horses and mules, significantly higher [SAA] were measured on days 1, 3, and 5 after EHV-1/-4 vaccination; [SAA] on day 1 after vaccination were only measured in animals that developed fever, where mean [SAA] were significantly higher in horses than in mules (horses: 1,365.75 ± 87.64 mg/L, mules: 615.5 ± 153.444 mg/L) (P > .05). Four horses and 2 mules developed fever after vaccination, lasting for ≤24 hours. Increased antibody responses (VN-T) on days 7 and 14 after vaccination were observed in all animals, whereas mules showed higher overall antibody responses. Nevertheless, [SAA] did not correlate with the intensity of the antibody responses (VN-T) stimulated by the vaccine (P < .05). EHV-1/-4 vaccination caused a prominent APR, higher in horses than in mules, but [SAA] did not correlate with antibody responses. Measuring [SAA] after vaccination could help identify severe APRs that may require longer resting intervals before training or competition.

Donkey and Mule Behavior

Donkeys and mules often are misunderstood because of their behavioral differences compared with horses. Working with these animals requires more patience and ability to notice the slightest changes in behavior to diagnose disease. Mules and donkeys form strong bonds and trust with familiar people and other equids. Training mules and hinnies from an early age is key to modifying behavior and acceptance of unfamiliar people. Reproductive behavior is different from that of horses and requires more patience when collecting jacks. Practitioners working with mules and donkeys should take a methodological approach and get to know the animal before performing examinations.

Key Aspects of Donkey and Mule Reproduction

Donkeys are nonseasonal, polyestrous, territorial, and nonharem breeders. Although there are many similarities between horses and donkeys, there are also reproductive features that differ, from the longer cervix in the jenny to spermatogenic efficiency in the jack. Mules display reproductive cyclic activity but are rarely fertile. Frozen donkey semen has high pregnancy rates in mares, but lower rates in jennies. This article reviews key aspects of donkey and mule reproductive physiology, reproductive medicine, and assisted reproductive techniques that are useful for practitioners offering assisted reproductive techniques, and also for practitioners with the occasional client with a basic reproductive question.

Determining factors and interspecific modeling for serum amyloid a concentrations in working horses, donkeys, and mules

Serum amyloid A (SAA) is an acute phase protein and α-globulin that is produced in the liver in response to inflammatory cytokines. Considered a major acute phase protein in most domestic species, its concentrations rapidly decrease after resolution of inflammation, making SAA measurement a useful tool for monitoring the course of inflammation in an individual animal. The objective of this study was to compare SAA values in working equids including mules, donkeys and horses as well as values for different diseases at various times of the year. Samples were collected from 77 equids; 13 mules, 17 donkeys and 47 horses from sick or injured animals who presented to the clinic. Twenty-eight disease clinical diagnoses were compared with most cases being acute colitis. A highly significant differences between species was found when comparing SAA concentrations of mules to horses (P < .001) using Dunn comparison pairwise test. A difference (P < .05) was found between donkeys and horses, but not donkeys to mules (P > .05). The study suggests that SAA can be a helpful tool for disease diagnosis in mules and donkeys and suggests that the inflammatory response of mules maybe less than that of horses and donkeys but future studies evaluating SAA in healthy mules compared to diseased should be conducted.

Epidemiological survey of equine influenza in Andalusia, Spain

Equine influenza is a highly contagious respiratory disease considered the most important respiratory disease in equids. Although influenza A virus (IAV) has caused outbreaks in equids worldwide, surveillance in these species in Spain has not been conducted. A cross-sectional study was carried out to determine the individual and herd prevalence of antibodies against H3N8 and H7N7 IAV in equids in Andalusia (southern Spain). Antibodies againsts IAV were measured by the single radial haemolysis assay. A spatial scan statistical analysis was carried out using a Bernoulli model. Risk factors associated with IAV infection were assessed by multivariate analysis. Antibodies to H3N8 IAV were detected in 241 out of 464 unvaccinated equids (51.9%; 95% CI: 47.4-56.5). Seropositivity against the H7N7 subtype IAV was not found in any of the analysed animals. Significantly higher seropositivity was found in geriatric (OR = 6.1, P = 0.008, 95% CI = 1.6-23.1) and adult (OR = 4.8, P < 0.001, 95% CI = 2.5-9.0) equids compared to young animals. Specific antibodies against A/equine/Shropshire/2010 (H3N8) or A/equine/Newmarket/5/2003 (H3N8) only were confirmed in 11 and 45 of the animals, respectively. The spatial analysis showed a statistically significant cluster centred in the west part of Andalusia. The results confirmed widespread H3N8 subtype IAV exposure in equine species in Andalusia. Conversely, the absence of seropositivity against H7N7 IAV obtained in the present study suggests that this subtype has not circulated in southern Spain in recent years. Because of the animal health and economic consequences of IAV in equids, further surveillance and molecular studies are required to monitor and characterize the most prevalent IAV circulating in these species in Spain.

Guaiphenesin-ketamine-xylazine infusion to maintain anesthesia in mules undergoing field castration

Background

In order to determine whether a combination of guaiphenesin, ketamine and xylazine can induce safe and satisfactory anaesthesia in mules undergoing field castration, eight healthy adult intact male mules were employed. They were premedicated with intravenous (IV) xylazine (1.3 mg/kg); an additional dose of xylazine (0.3 mg/kg IV) was administered in case of inadequate depth of sedation. Anaesthesia was induced with IV thiopental (6 mg/kg). The quality of sedation and induction was recorded. Anaesthesia was maintained with an infusion of guaiphenesin (50 mg/mL), ketamine (2 mg/mL) and xylazine (1 mg/mL) (GKX). The spermatic cord of each testis was infiltrated with 5 mL of 2% lidocaine. During anaesthesia heart rate (HR), respiratory rate (RR), rectal temperature (RT) and haemoglobin oxygen saturation (SpO₂) were measured every 5 min. The data were analysed with simple one-way analysis of variance (ANOVA). A P value < 0.05 was considered statistically significant. Time of anesthesia, time of surgery and time of recovery were recorded.

Results

Only one mule required an additional dose of xylazine to achieve a satisfactory depth of sedation. Thiopental at the dose of 6 mg/kg IV resulted in smooth induction and lateral recumbency in all animals. GKX provided adequate anaesthesia to perform castration in all mules. Muscle relaxation was deemed adequate and physiological variables remained stable and within references values during the anaesthesia and did not change in response to surgical stimulation. Time (mean ± standard deviation) from the end of the infusion to sternal recumbency and time from sternal recumbency to standing were 27.7 ± 4.6 and 30.1 ± 7.7 min, respectively.

Conclusions

The combination of xylazine, thiopental and GKX provides satisfactory short-term anaesthesia in mules undergoing field castration.