Oxidative Stress Associated With Spasmodic,Flatulent, and Impaction Colic in Draft Horses

The aim of the present study was to evaluate the oxidative stress level and antioxidant trace elements status associated with spasmodic, flatulent, and impaction colic in draft horses. For this purpose, venous blood samples were obtained from 20 randomly selected clinically healthy draft horses (control group) and 60 draft horses with different types of colic (spasmodic colic, n = 20; flatulent colic, n = 20; and impaction colic, n = 20). In horses with flatulent and impaction colic, there was a significant (P < .05) decrease in the total antioxidant capacity and activity of reduced glutathione (GSH) and catalase (CAT) as well as level of selenium, copper, zinc, and iron. However, there was a significant (P < .05) increase in the activity of superoxide dismutase (SOD) and in the level of malondialdehyde (MDA), interleukin-6 (IL-6), and manganese. Meanwhile, glutathione reductase (GR) was significantly (P < .05) increased in flatulent colic and significantly (P < .05) decreased in impaction colic. The oxidative stress index (OSI) was significantly (P < .05) increased in horses with flatulent and impaction colic. In horses with flatulent colic, there was a negative correlation between CAT and SOD (r = −0.446), MDA and zinc (r = −0.450), and IL-6 and zinc (r = −0.470). However, those with impaction colic, a negative correlation was recorded between CAT and MDA (r = −0.602), copper and GSH (r = −0.474), iron and GR (r = −0.511), and OSI and GR (r = −0.662). The results of the present study indicate that oxidative stress, with alteration of antioxidant trace element levels, is a feature of flatulent and impaction colic in draft horses.     

Evaluation of Urinary Variables as Diagnostic Indicators of Acute Kidney Injury in Egyptian Draft Horses Treated With Phenylbutazone Therapy

The present study was undertaken to evaluate the diagnostic significance of various urinary variables to detect acute kidney injury (AKI) in Egyptian draft horses treated with phenylbutazone (PBZ) therapy. Medical records of 52 draft horses, with a history of musculoskeletal painful conditions and treated frequently with various daily doses of injectable PBZ, were reviewed. Of those 52 horses, 38 were enrolled in this study. AKI was tentatively diagnosed based on thorough history and clinical findings and in conjunction with multiple biochemical screening tests. Accordingly, diseased horses were categorized into two main groups; the first group included 14 horses with prerenal azotemia, whereas the second group included 24 horses with renal azotemia. Biochemically, urinary malondialdehyde, urinary gamma-glutamyl transferase/creatinine (Cr) ratio, urinary protein/Cr ratio, urinary glucose, urinary sodium, fractional excretion of sodium, and renal failure index were significantly higher (P < .05) in horses of group 2 than those of group 1. However, values of urinary Cr, urine/plasma Cr ratio, urinary urea, and urine/plasma urea ratio were significantly decreased (P < .05) in horses of group 2. Analysis of receiver operating characteristic curve showed high sensitivity and specificity of most tested urinary variables as well as their derived indices for detection of AKI in diseased horses. Our findings suggest that the examined urinary variables as well as their ratios are helpful in documenting AKI associated with PBZ nephrotoxicity in Egyptian draft horses; however, their interpretation should be done in the light of the specific clinical setting and in conjunction with a thorough clinical and physical examination.     

Biochemical and Antioxidant Changes in Plasma, Serum, and Erythrocytes of Horses before and after a Jumping Competition

We designed an experiment to determine the concentrations of a marker of lipid peroxidation in erythrocytes of horses submitted to jumping competitions. Erythrocytes of exercised horses showed a significant increase in the concentration of thiobarbituric acid-reactive species content immediately after exercise (P < .001), which returned to normal levels 24 hours after exercise. Nonprotein sulfhydryl groups and superoxide dismutase activity (EC 1.15.1.1) in erythrocytes were significantly higher 24 hours after exercise, as compared with the resting period and control group (P < .001). Immediately after exercise, horses had increased serum concentrations of uric acid (P < .002) and plasma lactate, as well as increased creatine kinase (EC 2.7.3.2) and lactate dehydrogenase (EC 1.1.1.28) activities (P < .001), as compared with resting period and control group. All parameters returned to normal values 24 hours after exercise, except for uric acid serum levels that remained increased (P < .001). We conclude that the oxidative stress in erythrocytes of exercised horses may contribute to tissue damage. In addition, our results showed that horses submitted to a jumping competition showed higher production of free radicals and as a consequence, lipid peroxidation.     

Conflict Behavior in Show Jumping Horses: A Field Study

The study objective was to determine if there was a relationship between behavioral and physiological stress measures in sport horses and their performance. Nineteen horses competed in show jumping events (6 housed at the center and 13 transported), while 5 horses at home training served as controls. The competition horses were assigned to “light” (obstacles ≤100 cm) and “difficult” class (obstacles >100 cm). The conflict behaviors (CBs/min) in two rounds were calculated. Total faults were classified as “less faults” (≤one fault) or “more faults” (>one fault). Salivary cortisol concentration (SCC) before the first round (SCC-SP1), 20 minutes (SCC-SP2), and 60 minutes after the second round (SCC-SP3) was measured. The increase (SCC-in) and decrease (SCC-dec) in SCC were calculated. No effect of competition was found. Horses that waited longer for the second round had greater CB (P < .05). Conflict behavior was more frequent in horses from the “more faults” (P = .05) and “difficult” (a tendency; P = .06) classes. No correlation of CB with SCC was found. SCC-SP2 was greater in “more faults” (P < .01) and “transported” (P < .01) horses. Competition increased the SCC (P < .05), whereas SCC-SP2 was greater in less successful horses (P < .05). Transported horses and horses with more faults had the greatest SCC-SP2 and SCC-dec (P < .05). Our results suggest that horses which presented stress response were also less successful in competition. The adoption of effective methods to reduce transport and competition stress could enhance welfare and performance of sport horses during competition.     

Treatment With Platelet Lysate Inhibits Proteases of Synovial Fluid in Equines With Osteoarthritis

Osteoarthritis (OA) is the most prevalent arthropathy in sport horses. The administration of a platelet lysate (PL) is an alternative method for the treatment of musculoskeletal conditions. The mechanisms by which PL exerts its beneficial effects have not been determined, and less is known about its effect on the activity of the proteolytic enzymes of the synovial fluid of equines with OA. In this work, the effect of the administration of PL to horses with OA was analyzed both clinically and molecularly by determining the levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), glycosaminoglycans (GAGs), and tissue inhibitor of metalloproteinase 1 (TIMP-1) in synovial fluid. One mL of PL was administered intra-articularly followed by the extraction of synovial fluid on days 0, 10, 30, and 60. Results were evaluated by an analysis of variance for repeated measures. The levels of MMP-9 decreased significantly (P < .05) on day 10 after treatment with PL. A disintegrin and metalloproteinase with thrombospondin motifs 5 decreased significantly on days 10 (P < .05), 30 (P < .05), and 60 (P < .01) after treatment. The levels of synovial TIMP-1 increased significantly on day 30 (P < .001) after treatment. Glycosaminoglycans showed a significant increase on days 10 (P < .05) and 30 (P < .01). A significant decrease was found for MMP-2 on day 10 (P < .01), 30 (P < .01), and 60 (P < .001). In conclusion, the beneficial effects of PL in OA could be attributed to the decreased activity of MMP-2, MMP-9, and ADAMTS-5 and the increased concentration of GAGs and TIMP-1 after the administration of platelet-rich plasma.     

Factors Affecting Gestation Length in Heavy Draft Mares

The purpose of this study was to examine the factors affecting gestation length in 209 foalings from 65 heavy draft horses by multiple linear regression analysis. The objective variable was gestation length, and the explanatory variables were stud farm, year foaled, month foaled, age of mare, parity of mare, last gestation length, foal gender, and some meteorological parameters (the mean values of prepartum 10 days: maximum temperature, minimum temperature, average barometric pressure, and hours of sunshine in a day). The mean gestation length for 209 foalings was 334.9 (standard deviation = 8.3) days, with a range of 313-352 days. Stepwise regression analysis showed that last gestation length and foal gender had significant (P < .01) effects on gestation length. Multiple regression analysis showed that last gestation length (standard partial regression coefficient = 0.54) was more influential on the present gestation length than foal gender (standard partial regression coefficient = 0.22). The present gestation length and the last gestation length were moderately positively correlated (r = 0.56, P < .01). Colt foal (n = 106) pregnancies were significantly (P < .01) longer than fillies (n = 103) (mean ± SEM: colt 337.1 ± 0.7 vs. filly 332.7 ± 0.9). According to our results, last gestation length (mare itself) and foal gender were the main factors affecting gestation length in heavy draft horses. Once several gestation lengths are known, predictions with acceptable accuracy can be made about the gestation length of that mare's following foaling.     

The Effect of Season on Muscle Growth,Fat Deposition,Travel Patterns,and Hoof Growth of Domestic Young Horses

Our objective was to determine the influence of season (winter, spring, summer, and fall) on travel patterns, hoof growth, and longissimus dorsi muscle (LM) height and fat thickness between 13th and 14th ribs in 16 horses aged <4 years (eight males and eight females) of Morgan, Quarter Horse, and Moriesian breeds. Real-time ultrasound images of LM height and fat thickness as well as measures of hoof growth were obtained at the end of each season. Global positioning system tracking was conducted for four randomly selected days and one storm day in each season. Data were analyzed using a linear mixed model procedure in SAS. Season influenced fat deposition (P < .01) with the greatest increase in fall (P < .05) but had minimal effect on muscle growth. Hoof growth was greatest in summer and least in winter (P < .01). The average distance traveled was greater in spring and summer than in fall and winter (P < .01). The horses moved for less time and traveled less distance on storm days (P < .05) compared with nonstorm days. Young horses also traveled less on storm days, which indicates that it may be especially important to provide shelter for them. It was concluded that season influenced fat deposition, distance traveled, and hoof growth of domestic young horses. A better understanding of these factors could help equine professionals manage young horses more efficiently to benefit the horses’ physical well-being.     

Effect of Experience on Adrenocortical and Thyroid Responses of Arabian Horses to Gymkhana Games

Gymkhana is an equestrian event consisting of speed pattern racing and timed games for riders on horses. The aim of the study was to evaluate the effects of gymkhana competition on total cortisol and total and free iodothyronine changes in 23 Arabian purebred horses, by taking into account the effects of previous sport experience on gymkhana riding events. Compared with pre-competition values, an increase of total cortisol concentration has been observed in experienced horses at 30 minutes (P < .001) after exercise and in inexperienced horses both at 5 minutes (P < .05) and at 30 minutes (P < .01) after exercise. Compared with pre-competition values, an increase of total triiodothyronine (T₃) concentration has been observed in experienced horses at 5 minutes (P < .05) after exercise. Data obtained showed that gymkhana riding events induced differential adrenocortical and thyroid responsiveness according to previous experience of sport horses. Hence, cortisol and iodothyronine patterns may provide additional information for the monitoring of gymkhana riding performance.     

Horses Seropositive for Neospora spp.: Immunoglobulins,Cytokines, and C-Reactive Protein Levels

Neosporosis is a disease known to cause reproductive problems in cattle. In horses, the disease is caused by the protozoa Neospora caninum and/or Neospora hughesi, but little is known about this infection in this species. Therefore, the aim of this study was to quantify the levels of immunoglobulins (Igs), cytokines, and acute phase protein in seropositive horses for Neospora spp. (n = 23) comparing with seronegative horses (n = 20). There was no significant difference (P > .05) between IgG levels; however, IgM levels were significantly higher in sera samples from positive animals (P < .01). Similarly, proinflammatory cytokines (tumor necrosis factor, interferon gamma, interleukins [IL-1, IL-4, and IL-6]) and C-reactive protein levels were also significantly higher (P < .01) in horses seropositive for Neospora spp. On the other hand, the IL-10 levels (anti-inflammatory cytokine) were lower in horses seropositive for neosporosis (P < .01). Therefore, we conclude that horses naturally infected by Neospora spp., even without clinical disease, are able to activate their immune systems to control the infection, which may lead to disease chronicity.     

Effect of Age and Performance on Physical,Hematological, and Biochemical Parameters in Endurance Horses

Endurance horses are subjected to heightened stress even after several conditioning protocols. Hence, the goal of this study was to examine the effect of age and performance on the hematology, biochemistry, and physical parameters after an endurance race. Eighteen horses aged 6-15 years were grouped into 80-km race category. All the horses were physically examined, and blood samples were collected postrace. After physical examination, the poor (n = 9) and good (n = 9) performance horses were identified. Potassium concentration was significantly higher (P < .05) in the good performance horses; chloride concentration was significantly higher (P < .05) in the poor performance horses. The mean blood glucose concentration of the poor performance horses in all the age-groups was significantly higher (P < .05). The mean blood lactate concentration was significantly lower (P < .05) in the poor performance horses. There was significant effect of performance on heart rate (P < .031), capillary refill time (P < .013), and gut motility (P < .05). Univariate Fisher exact test results were significantly higher for skin recoil (P < .03), mucous membrane (P < .03), and gait (P < .04) in the performance categories. In conclusion, the influence of age was seen in the poor performance category in relation to lactate, but age did not influence other physical, hematological, and biochemical parameters of the endurance horses. Thus, further studies are required to determine whether physical, hematological, and biochemical parameters during training could be used to estimate performance in endurance horses based on age.     

Hematological and Blood Biochemical Characteristics of Newborn Heavy Draft Foals After Dystocia

The negative impact of equine dystocia on hematological and serum biochemical profile of neonatal foals remains unknown, particularly in heavy draft horses that show high incidence of dystocia. This study aimed to reveal the hematological and serum biochemical profile of the foals born in normal delivery and examine the effect of dystocia on blood properties in heavy draft newborn foals. In the normal birth group (n = 23), stage II labor was <30 minutes, with spontaneous or assisted delivery with mild traction by one or two people. In the dystocia group (n = 13), stage II labor was ≥30 minutes, with strong traction by more than three people or mechanical tools with or without correcting fetal displacement. Blood samples were collected from the jugular vein at 0, 1, and 12 hours and 1 and 2 days after foaling. Red blood cells, hemoglobin concentration, and packed cell volume remained significantly lower in the dystocia group than in the normal birth group. The white blood cell count was significantly higher in dystocia foals (1 day: P < .05). Dystocia foals had significantly higher cortisol (1 hour: P < .05), urea nitrogen (1 hour: P < .05), and creatine kinase activities (1 hour: P < .01, 12 hours: P < .05). This study revealed that dystocia foals were more likely to be affected by anemia, physical stress, and muscle damage than normal birth foals.     

Relationship Between Neutrophil Activity,Oxidative Stress,Acute Phase Response,and Lameness Grade in Naturally Occurring Acute and Chronic Joint Disorders in Horses

We hypothesized that in horses with naturally occurring joint disorders, the neutrophil response, acute phase response (APR), and oxidative stress parameters elevated significantly and are markers of increased inflammatory response in these conditions. Therefore, the first aim of the study was to evaluate neutrophil response, oxidative status, and APR. The neutrophil activity was assessed on the basis of elastase, myeloperoxidase (MPO), and alkaline phosphatase release, whereas free radical generation was assessed on the basis of nitric oxide and superoxide production. Acute phase response was estimated on the basis of fibrinogen or haptoglobin plasma concentration and oxidative stress on the basis of malondialdehyde plasma concentration. Then, these parameters were compared with lameness grade, and correlation coefficients between them were calculated. The study was conducted on 43 horses divided on control group of healthy horses (n = 17), acute lameness (AL) group (11 horses), and chronic lameness (CL) group (15 horses). The neutrophil activity from horses of both groups of joint disorders (AL and CL) was significantly (P < .01) higher in comparison with healthy horses. Elastase release was 67.28 ± 1.89% of maximal activity in AL group in comparison with 51.72 ± 1.75% in healthy horses and 62.61 ± 1.54% in CL group. The highest values of other enzymes were also noted in AL group. Moreover, in AL group release of elastase and MPO positively correlated (P < .01) with grades of lameness. These findings revealed the mutual relation between studied parameters and obtained results may be useful in the development of new therapeutic strategies in the treatment of acute and chronic joint disorders in horses.     

The Potential Role of Training Sessions on the Temporal and Spatial Physiological Patterns in Young Friesian Horses

This study compares the circulating adrenocorticotrophin hormone (ACTH), cortisol, lactate, glucose, heart rate, respiratory rate, rectal temperature, and blood count values in initially 2-year-old horses subjected to dressage training schedule during three consecutive days per 2 weeks. Sixteen healthy Friesian horses were used and were considered dressage group. Six healthy young horses not involved in training programs were used as control group. Blood sampling were collected from the jugular vein in baseline condition (dressage group and control group) and after exercise, within 5 minutes of the end of the training session (dressage group). Compared to baseline values, results showed higher ACTH concentrations after the first day of the first training week (P < .005) and after the third day of the second week (P < .005); higher lactate concentrations after the second and the third day of the second week (P < .01); lower glucose concentrations after the third day of the first week (P < .01); higher HR, RR, and RT values and lower PLT count after different time points during both training weeks. One-way ANOVA showed significant training effect for ACTH (F = 7.605; P < .0001) and glucose (F = 3.505; P < .001) concentrations over time points. Two-way ANOVA showed a significant effect of dressage training sessions between the first and the second week for ACTH (F = 6.508; P < .001) and cortisol (F = 5.559; P < .0001) concentrations. From obtained data, it seems that the use of ACTH and cortisol changes for the assessment of effects of training in initially 2-year-old horses could be an ideal measure of quantitative and qualitative stress responses. The quantification at the same time of functional responses to stressful stimuli may offer a more objective measurement of dressage training effects.     

Prevalence and Potential Risk Factors of Dermatophytosis in Arabian Horses in Egypt

The objective of the present study was to verify the prevalence and the risk factors associated with dermatophytosis in Arabian horses. For this purpose, a total of 457 Arabian horses in 15 farms were examined. A questionnaire was constructed to include the hypothesized risk factors. Fungal isolation and identification for each horse were carried out by standard microbiological procedures. Logistic regression analysis was used to evaluate the risk factors on both animal and farm levels. Trichophyton spp. was recovered from 50 horses and Microsporum spp. from 27 cases. Trichophyton equinum was more prevalent than Trichophyton mentagrophytes (45 vs. 4) and Trichophyton tonsurans (45 vs. 1). However, Microsporum canis was more prevalent than Microsporum gypseum (21 vs. 5) and Microsporum audouinii (21 vs. 1). On horse level, final multivariate logistic regression analysis showed that there was a significant association between dermatophytosis and horse' age (P < .05; odds ratio [OR]: 1.07; 95% confidence interval [CI]: 1.0–2.69), poor grooming practice (P < .05; OR: 57.11; 95% CI: 2.47–13.44), moist condition (P < .05; OR: 42.77; 95% CI: 2.0–25.18), and farm size (P < .05; OR: 1.06; 95% CI: 1.00–7.05). However, on the farm level, farm size of >30 horses was the risk factor (P < .05; OR: 1.0; 95% CI: 1–3.03). In conclusion, the present results indicate existance of dermatophytosis in Arabian horses. Identification of the potential risk factors associated with the disease may be helpful to construct the ideal preventive measures.     

Acupuncture Needle Stimulation on Some Physiological Parameters After Road Transport and Physical Exercise in Horse

The aim of this study was to evaluate the effect of acupuncture (AG) treatment on some hematochemical parameters in five Thoroughbred horses after road transport and exercise. Horses competed in two official races. For each race, animals were transported from their stables to the racetrack. Horses transported and competed in the first race represent the control group. Two weeks later, the same horses competed in the second race. Before road transport, they were treated with AG. From animals, blood samples were collected at rest (T_PRE), after unloaded (T_POST), 30 minutes after unloaded (T_POST30), at rest in the transit stall (R_PRE), at the end of the race (R_POST), and 30 minutes after the race (R_POST30). The effect of transport, exercise, and AG was evaluated on blood lactate, glucose, red blood cell, hemoglobin, hematocrit, mean corpuscular volume, and erythrocyte osmotic fragility (EOF) values. A significant effect of transport (P < .05) and exercise (P < .01) was found on all studied parameters in both groups. A significant effect of AG on lactate, glucose, and EOF values was found in transported (P < .001) and exercised horses (P < .05). The results found in this study showed that transport and exercise are potential stressors for the athlete horse that may affect its welfare and physical performance. The data suggest that AG stimulation promoted the increase of blood glucose values and the reduction of lactate and EOF levels suggesting its role in the improvement of the physiological adaptation to stressful stimuli and of physical performance of Thoroughbred horses.     

Erythrocyte Osmotic Fragility and Hematological Responses of Horses Administered Ascorbic Acid and Exposed to Road Transportation

The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties.     

Influence of Acute Exercise on Serum Homocysteine in Horse

The effect of acute exercise on serum homocysteine (sHCy) concentration was examined in 10 horses; five Sella Italiana and five Thoroughbreds. All horses underwent standard training before the study (show jumping for Sella Italiana horses and gallop racing for Thoroughbreds). For the study, blood samples were taken at rest, immediately after exercise, and during a recovery period (30 and 60 minutes after exercise) by external jugular venipuncture. sHCy values were determined by high-performance liquid chromatography. Heart rate and blood lactate were monitored to quantify the workloads. In show jumpers, there was a significant effect of sampling time on sHCy (P < .01), which increased significantly after exercise as compared with at rest. In Thoroughbreds, no statistically significant differences were observed in sHCy over time (F_(3,12) = 0.89, P = .05). The baseline values of sHcy were higher in Thoroughbreds than in show jumpers (P < .0002). We infer that physical activity causes biochemical changes that can influence the metabolic pathway of homocysteine in show jumpers, whereas the absence of a significant effect of exercise in Thoroughbreds may reflect an adaptive response of the enzymatic antioxidant defense system.     

Distances Walked by Long Established and Newcomer Horses in an Open Stable System in Northern Germany

Group housing is claimed to possibly provide horses with a species-appropriate movement possibility, and hence, better welfare. Thus, this study analyzed the daily walked distances of 51 horses held in one group in a “HIT Active Stable” (Hinrichs Innovation + Technik) in Northern Germany by using global positioning system (GPS) technology during a 7 ½-month time span. The daily walking distances of the whole group, as well as newcomers, were investigated. The horses traveled an average of 8.43 km/day. Linear mixed models were applied. The observation day had a significant effect on the daily walking distances (P < .01) due to season and the available area per horse. The age as covariate also had a significant effect (P < .01). The breed had no significant effect (P = .96). No significant differences were found in sex (P = .69), which can be explained by the fact that only mares and geldings were investigated, which do not show increasing locomotion caused by sexual behavior as stallions do. On six of the first nine days, new horses moved significantly more compared to the remaining 24 of the 30 observation days directly after individuals’ inclusion. This is probably due to more exploration and rank-fighting behavior. Similar walking distances were seen among the horses on the single observation days because all horses had to travel the same distance to reach resources. Further, it is suspected that not all horses can sufficiently live out their urges to move, especially in winter, when pasture is inaccessible.     

Antithrombin: Could It be a Diagnostic and Prognostic Marker in Septic Neonatal Foals?

Antithrombin (AT) levels are lower in human neonates affected by sepsis and in nonsurvivors compared with survivors. The aims of this study were to evaluate AT profile in healthy newborn foals and its diagnostic and prognostic role in septic foals during the first week of life. Fifteen healthy foals and 35 septic foals were enrolled. Blood samples were collected from each healthy foal at 30 minutes, 3 and 12 hours from birth, daily from days 1–7, and at days 10 and 14. Blood was collected from each septic foal twice a day from admission to discharge or death. The AT analysis was performed by chromogenic method. Healthy foals showed decreasing levels of AT between 3 hours and 2 days, followed by an increasing trend. Septic foals did not show any difference during the period of observation, and no differences were found between healthy and septic age-matched foals. The analysis of AT activity on the day of admission in septic foals showed higher levels compared with healthy foals, in animals hospitalized at 12 and 24 hours of age (P < .01). No differences were found at admission between foals affected by sepsis and that with septic shock. Nonsurviving foals showed significantly lower levels at 3 and 4 days of age compared with surviving foals; when surviving and nonsurviving foals were compared independently by the age, nonsurviving foals showed significant (P < .05) lower levels 12 hours after admission. In conclusion, AT seems to show neither a diagnostic nor a prognostic role in septic neonatal foals.     

Oxidative stress in farmed minks with self-biting behavior

Self-biting behavior (SBB) is a serious behavioral disorder in farmed minks, but little is known about the biological basis of this disorder. The present study examined for the first time the hepatic and cerebral oxidative stress biomarker levels in SBB minks and compared them with those in normal ones to study the association of oxidative stress and SBB in minks. Calcium-activated adenosine triphosphatase (Ca²⁺ATPase) activities were also determined to investigate whether the Ca²⁺ pump in brain is affected. Twenty male SBB minks and 20 male normal minks were chosen in December. The brain and liver of each mink were harvested immediately after slaughter to test oxidative stress biomarkers. All parameters were determined by using a spectrophotometer. Our findings were as follows: SBB minks produced more malondialdehyde with 51% increase in brain (P < 0.01) and 22% increase in liver (P < 0.01) compared with normal minks. Similarly, the hepatic and cerebral protein carbonyls in SBB minks were 18.5% (P < 0.01) and 30% higher (P < 0.001), respectively. Glutathione peroxidase activities in brain and catalase activities in both tissues of SBB minks were markedly lower than those of normal group (P < 0.01). However, SBB minks had higher total superoxide dismutase (SOD), Cu/Zn-SOD, and Mn-SOD activities in both tissues (P < 0.05 or P < 0.01). Significant depletion of glutathione and vitamin E levels were observed in SBB minks (P < 0.01 or P <0 .05). Calcium-activated adenosine triphosphatase activities in the brain of SBB minks were inhibited (P < 0.01). Our results supported the oxidative stress hypothesis in minks with SBB.