Esterina Fazio

Evaluation of stress during transport

Domestic animals are transported for a variety of reasons including breeding, biomedical purposes, slaughter and, in the case of sporting horses, for competitions, pleasure activities or ceremonial proceedings. Studies to determine the amount of stress on farm animals during transport often have highly variable results and are difficult to interpret. The reaction of animals to stressors depends on the duration and intensity of the stressors, the animals previous experience, its physiological status and the immediate environmental restraints. Behavioural, haematological, haematochemical, physiological and neuro-hormonal (β-endorphin, ACTH, cortisol, iodothyronines) variables are discussed on the basis of handling, loading and transport procedures of animals.

Circulating β-endorphin, adrenocorticotrophic hormone and cortisol levels of stallions before and after short road transport: stress effect of different distances.

BackgroundSince transport evokes physiological adjustments that include endocrine responses, the objective of this study was to examine the responses of circulating β-endorphin, adrenocorticotrophic hormone (ACTH) and cortisol levels to transport stress in stallions.MethodsForty-two healthy Thoroughbred and crossbred stallions were studied before and after road transport over distances of 100, 200 and 300 km. Blood samples were collected from the jugular vein: first in a single box immediately before loading (pre-samples), then immediately after transport and unloading on arrival at the breeding stations (post-samples).ResultsAn increase in circulating β-endorphin levels after transport of 100 km (P < 0.01), compared to basal values was observed. Circulating ACTH levels showed significant increases after transport of 100 km (P < 0.001) and 200 km (P < 0.001). Circulating cortisol levels showed significant increases after road transport over distances of 100, 200 and 300 km (P < 0.001). An effect of transport on β-endorphin, ACTH and cortisol variations was therefore evident for the different distances studied. No significant differences (P > 0.05) between horses of different ages and different breeds were observed for β-endorphin, ACTH and cortisol levels.ConclusionThe results obtained for short term transportation of stallions showed a very strong reaction of the adrenocortical system. The lack of response of β-endorphin after transport of 200–300 km and of ACTH after transport of 300 km seems to suggest a soothing effect of negative feedback of ACTH and cortisol levels.

Effects of competition experience and transportation on the adrenocortical and thyroid responses of horses

To evaluate whether the amount of experience of sport horses and the stress of transport affected their adrenocortical and thyroid responses, the plasma concentrations of total cortisol and total and free iodothyronine of 63 horses were studied before and after show jumping competitions. There were 14 trained inexperienced jumpers (group 1), 20 trained experienced jumpers (group 2), 10 trained inexperienced jumpers that had been transported just before the competition (group 3) and 19 trained experienced jumpers that had been transported just before the competition (group 4). The concentrations were measured under basal conditions and five and 30 minutes after the competition. There were significant increases relative to the basal values in the total cortisol concentrations of all four groups of horses at five and 30 minutes (P<0·001), but there were no significant differences between the groups. In contrast, there were no significant changes in the concentrations of triiodothyronine, thyroxine and free thyroxine after the competition and there were no significant differences between the groups. However, the horses in group 2 had significantly lower basal concentrations of free triiodothyronine than the horses in groups 1, 3 and 4 and the difference was maintained at five and 30 minutes after the competition.

Effect of long-distance road transport on thyroid and adrenal function and haematocrit values in Limousin cattle: influence of body weight decrease.

The purpose of this study was to evaluate the effect of long-distance road transport as a relevant stressor on total and free iodothyronines, cortisol levels and haematocrit values in 10 male Limousin cattle. Serum T3,T4,fT3,fT4 and cortisol concentrations were analysed by immunoenzymatic assays. Serum cortisol levels and haematocrit modifications were also evaluated on the basis of percentage body weight decrease. The results showed a general increase of total and free iodothyronines and cortisol levels after short-and long-distance road transport and a decrease 15 days after transport, as compared to basal values. Significant positive correlations between T3 and T4, between T3 and fT3, and between T4 and fT4 were found. These results suggest that transport stress induces an increase in the activity of thyroid and adrenal function in Limousin cattle that is evident after even a short-distance road transport and continues to increase after long-distance transport.

Comparative endocrinological responses to short transportation of Equidae (Equus asinus and Equus caballus)

In order to evaluate the effects of short transportation on β-endorphin, adrenocorticotropic hormone (ACTH) and cortisol changes, 12 healthy stallions of Equidae (Equus asinus and Equus caballus) were studied before and after transportation of 50 km. Blood samples were collected 1 week before transportation in basal conditions, immediately before loading and after transportation and unloading, on their arrival at the breeding station. Compared to basal and before values, donkeys showed an increase in circulating ACTH (P < 0.001) and cortisol (P < 0.0005) levels after transportation and higher ACTH (P < 0.01) levels than horses after transportation. A positive and significant correlation (r = 0.885; P < 0.01) between ACTH and cortisol levels after transportation was found. No significant differences were observed for β-endorphin levels. Compared to basal and before values, horses showed higher cortisol (P < 0.005) levels after transportation and no significant differences were observed for ACTH and β-endorphin levels in donkeys. Horses facing forward (direction of travel) showed higher (P < 0.01) β-endorphin levels after transportation than donkeys; horses facing backward (the opposite direction of travel) showed lower (P < 0.05) ACTH levels after transportation. The results indicate that short transportation induces a preferential activation of the hypothalamus-pituitary-axis (HPA), with significant release of ACTH and cortisol in donkeys and only of cortisol in horses, suggesting that transportation for donkeys may be more stressful than horses.

Cortisol and haematochemical variables of horses during a two day trekking event: effects of preliminary transport.

REASONS FOR PERFORMING STUDY Trekking is a noncompetitive sport, involving maximal skeletal muscle effort. Exercise and transport may involve significant energy expenditure and give rise to substantial stress. Few studies have examined the combined effect of exercise and additional preliminary transport on adrenocortical and haematochemical responses in horses during trekking. OBJECTIVES To ascertain whether exercise and additional preliminary transport before trekking would affect the circulating cortisol levels and haematochemical variables of horses during a 2 day trekking event. MATERIALS AND METHODS Twenty-nine healthy horses were used. Twenty-four horses were transported over distances of 70 km the day before trekking and 5 horses were stabled at the starting place. Blood samples were taken from horses at 16.00 h the day before trekking; and at 08.30 h and 17.30 h before and after the first day of trekking; at 08.30 h and at 13.30 h before and after the second day of trekking. Serum cortisol and haematochemical variables were determined in duplicate by using commercial test kits. One-way analysis of variance for repeated measures (RM-ANOVA) was applied to determine whether trekking and transport had any effects. RESULTS Trekking significantly (P < 0.01) affected total protein, albumin, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), PCV and cortisol changes in transported horses and only urea and PCV (P < 0.01) changes in untransported horses. Untransported horses showed lower basal total protein (P < 0.05) and albumin (P < 0.01) concentrations, higher urea concentrations (P < 0.001) at the second day and lower cortisol levels after the first and the second (P < 0.05) day of trekking than transported horses. CONCLUSION These data show that the preliminary transport stress induced additional significant changes of cortisol and haematochemical patterns in horses after trekking.

Effects of competitive and noncompetitive showjumping on total and free iodothyronines, β-endorphin, ACTH and cortisol levels of horses

REASONS FOR PERFORMING STUDY Limited knowledge exists about the differentiated effects of competitive and noncompetitive showjumping on thyroid function and relationships with hypothalamic-hypophysis-corticoadrenal hormones. OBJECTIVES To obtain preliminary data about differentiated effects of competitive and noncompetitive showjumping on total and free iodothyronines, β-endorphin, ACTH and cortisol of horses. MATERIAL AND METHODS Five trained healthy jumper horses were studied during competitive and noncompetitive showjumping, performed in the same circuit design over 10 fences of 1.10 m. Hormone levels before, 5 and 30 min post exercise were recorded. Serum iodothyronines and cortisol concentrations were measured in duplicate utilising EIA kits. Serum ACTH and plasma β-endorphin concentrations were analysed in duplicate utilising RIA kits. Two-way RM ANOVA was applied to test for effects of interaction between different type of session and time. Significant differences between post exercise and basal values were established using Bonferronis multiple comparison test. A linear correlation analysis (Pearsons method) was performed to analyse the relationships between total and free iodothyronines and between iodothyronines and β-endorphin, ACTH and cortisol. RESULTS In sampling times adopted no statistical different effects of type of session were recorded on hormone variables. Sampling time affected ACTH (F = 4.25; P < 0.02) and T(4) (F = 4.43; P < 0.02) post exercise changes. During the noncompetitive session, significant correlations existed between T(4) and β-endorphin (r = -0.56), ACTH (r = -0.65), between β-endorphin and ACTH (r = 0.52) and between T(3) and fT(3) (r = 0.72); during competition between β-endorphin and T(3) (r = -0.67), fT(3) (r = -0.59). CONCLUSIONS These preliminary results could demonstrate correlations between thyroid hormones and β-endorphin response to showjumping, although no definitive conclusion can be produced concerning the relationships between HPA and thyroid function during exercise.

Physiological variables of horses after road transport.

In order to investigate the effects of short road transport stress on total and free iodothyronines, body weight (BW), rectal temperature and heart rate (HR) changes, 126 healthy stallions were studied in basal conditions, before and after transport. A total of 60 Thoroughbred and 66 crossbred stallions aged 4 to 15 years with previous travelling experience were transported by road in a commercial trailer for a period of about 3 to 4 h (distance under 300 km). Blood samples and functional variables were collected in each horse box, one week before loading and transport in basal conditions (control samples), one week later immediately before loading (pre-samples) and again after transport and unloading (about 3 to 4 h) in each new horse box, within 30 min of their arrival at the breeding stations (post-samples). Compared to the before-transport values, increases in circulating T3, T4 and fT4 levels (P < 0.01) were observed after transport, irrespective of breed, but not for fT3 levels. Lower T4 and fT4 levels were observed in basal II (at 1100 h) (P < 0.01) than in basal I (at 0800 h) conditions and before transport. Thoroughbreds showed higher fT3 (P < 0.05) and fT4 (P < 0.01) levels after transport than crossbred stallions. No significant differences were observed for T3 and T4. Compared to the before-transport values, significant increases in rectal temperature (P < 0.01) and HR (P < 0.05) were observed after transport. No differences were observed between basal I, II and before values for functional variables. Significant correlations between T3 and rectal temperature, BW and HR were found. The results indicate that short road transport induces a preferential release of T3, T4 and fT4 hormones from the thyroid gland in relation to different breed, and an increase in rectal temperature and HR. No significant changes in BW were observed. No differences were observed in relation to different ages. The data obtained suggest that the stallions thyroid hormones and functional variables may play an important role in assessing the effects of transport stress and a horses coping strategy.

Effects of different health status on blood haematochemical values of loggerhead sea turtles (Caretta caretta)

In reptiles, several studies show the correlation between good or poor health and changes of physiologic parameters, but the comparison among data, methods and biochemical analysis in sea turtles are difficult. This study was carried out to investigate the biochemical patterns of total protein, albumin, creatinine, urea, alanine aminotransferase and aspartate aminotransferase (AST) in 100 loggerhead sea turtles (52 in good health, 16 with illness and 32 with serious illness). Blood samples were collected by venipuncture from the dorsal cervical sinus, the jugular vein or the ventral caudal sinus between March and October 2007 to 2009. Compared with subjects in good health, total protein and albumin concentrations were lower in subjects suffering from illness (p < 0.001) and in those with serious illness (p < 0.01). Compared with subjects with good health, creatinine concentrations (p < 0.001) and AST activity (p < 0.001) were lower in turtles with serious illness (p < 0.001), and urea concentrations were lower in subjects suffering from (p < 0.01). One-way repeated-measures analysis of variance showed significant effects of the health status of sea turtles on albumin (p < 0.05), urea (p < 0.001) and AST (p < 0.001) fluctuations. Data obtained showed a significant correlation between health status and haematochemical changes in sea turtles.

Pituitary-adrenocortical adjustments to transport stress in horses with previous different handling and transport conditions

Aim: The changes of the hypothalamic pituitary adrenal (HPA) axis response to a long distance transportation results in increase of adrenocorticotropic hormone (ACTH) and cortisol levels. The purpose of the study was to quantify the level of short-term road transport stress on circulating ACTH and cortisol concentrations, related to the effect of previous handling and transport experience of horses. Materials and Methods: The study was performed on 56 healthy horses after short-term road transport of 30 km. The horses were divided into four groups, Groups A, B, C, and D, with respect to the handling quality: Good (Groups A and B), bad (Group D), and minimal handling (Group C) conditions. According to the previous transport, experience horses were divided as follows: Horses of Groups A and D had been experienced long-distance transportation before; horses of Groups B and C had been limited experience of transportation. Results: One-way RM-ANOVA showed significant effects of transport on ACTH changes in Groups B and C and on cortisol changes in both Groups A and B. Groups A and B showed lower baseline ACTH and cortisol values than Groups C and D; Groups A and B showed lower post-transport ACTH values than Groups C and D. Groups A, B, and C showed lower post-transport cortisol values than Group D. Only Groups A and B horses have shown an adequate capacity of stress response to transportation. Conclusion: The previous transport experience and quality of handling could influence the HPA axis physiological responses of horses after short-term road transport.