Age-Related Differences in Short-Term Transportation Stress Responses of Horses

Monitoring the physiological inflammatory alertness in horse after road transport

The aim of this study was to assess the changes of pro-inflammatory interleukins in 10 horses subjected to road transport practices (distance of 150 km) from the training site (Messina, Sicily) to the competition centre in Syracuse (Sicily). Blood sampling and interleukins analysis were performed during a round trip transportation (transport 1 and transport 2). In particular, blood samples were collected before the transport took place (Pre), five minutes later (Post) and one hour later (Post 1 h), for each transport, in order to assess the serum concentration of IL-1α, IL-1β, IL-2 and IL-6. The results showed that the serum concentration of IL-1α decreased at Post and Post 1 h compared to the values obtained at rest condition (P < 0.05). The other interleukins analysed (i.e. IL-1β, IL-2 and IL-6) showed increased levels at Post than Rest and Post 1 h in transport 1 (P < 0.05). In transport 2 the analysed parameters showed no change throughout the analysed time points (P > 0.05); however, higher levels of IL-1α at Pre and higher IL-1β, IL-2 and IL-6 values at Post were found in transport 1 than transport 2 (P < 0.05). The increase in pro-inflammatory cytokines after transport 1 suggests the triggering of the inflammatory event and this may show that, although horses are animals accustomed to transport, this is a stressful event that could activate the well-orchestrated inflammation cascade, albeit physiological and temporary, as highlighted by the lower serum concentrations of the investigated interleukins found in transport 1 than transport 2 and by the lack of significant differences in the serum concentrations of the investigated interleukins among the time points of transport 2. It must be taken into account that enrolled animals are well-trained and healthy athletic horses participating to a jumper competition, thus, such inflammation did not occur thanks to a good balance between pro-inflammatory and anti-inflammatory cytokines which allowed a prompt restoration of homeostasis eventually impaired by the stressful event.

A survey of general road transportation: How and why horses are transported in the U.S

Horses are regularly transported in the United States (U.S.); however, how, and why horses travel by road has not been explored. Consequently, an online nationwide survey was conducted to understand 1) the most common reasons for travel; 2) the types of journeys undertaken when being transported by road in the U.S. and 3) the general management practices when transporting for 3 h or less. Responses were collected from 1294 participants with at least one response from every state in the continental U.S. The most common survey taker was a female (93.9 %), adult amateur (81.2 %), horse owner (64.6 %) who rode recreationally (33.1 %) and transported their own horse (79.4 %). The most common reasons for travel were for trail or leisure riding (34.2 %) followed by showing and competition (25.3 %); however, this varied by discipline. The most common trip duration was less than one hour (46.8 %), with only 12.4 % of the most common trip durations being 4 h or more. The most common specific horse transported by road for 3 h or less was an adult (age 5-15; 59.0 %), Quarter Horse (21.2 %), used for pleasure or trail riding (44.3 %). The biggest concern when transporting was injury to the horse (26.7 %), whilst the biggest factor when planning to travel was the weather (24.1 %). These results provide insight into why horses are being transported by road in the U.S. and that it is more common to transport horses for shorter durations.

Factors affecting measurement of basal adrenocorticotropic hormone in adult domestic equids: A scoping review

Measurement of basal adrenocorticotropic hormone (ACTH) concentration is the most commonly used diagnostic test for pituitary pars intermedia dysfunction (PPID). Although several pre-analytical and analytical factors have been reported to affect basal ACTH concentrations in equids, the extent to which these have been evaluated in the context of PPID diagnosis is unclear. The objectives of this scoping review were to identify and systematically chart current evidence about pre-analytical and analytical factors affecting basal ACTH concentrations in adult domestic equids. Systematic searches of electronic databases and conference proceedings were undertaken in June 2022, repeated in October 2022 and updated in August 2023. English language publications published prior to these dates were included. Screening and data extraction were undertaken individually by the authors, using predefined criteria and a modified scoping review data extraction template. After removal of duplicates, 903 publications were identified, of which 235 abstracts were screened for eligibility and 134 publications met inclusion criteria. Time of year, exercise, breed/type and transportation were the factors most frequently associated with significant increases in ACTH concentration (n = 26, 16, 13 and 10 publications, respectively). Only 25 publications reported inclusion of PPID cases in the study population, therefore the relationship between many factors affecting basal ACTH concentration and diagnostic accuracy for PPID remains undefined. However, several factors were identified that could impact interpretation of basal ACTH results. Findings also highlight the need for detailed reporting of pre-analytical and analytical conditions in future research to facilitate translation of evidence to practice.