Male Horses Research Articles

Cutaneous Leishmaniosis caused by Leishmania martiniquensis in a Horse in Florida

We report a new case of cutaneous leishmaniosis caused by Leishmania (Mundinia) martiniquensis in a horse in Florida, USA. A 10-year-old neutered male Quarter horse was presented with multifocal to coalescing, raised, ulcerated and oozing, non-healing wounds on both pinnae of several weeks' duration. After a few months, the lesions regressed spontaneously. Biopsies of the lesions were performed with microscopical findings of epidermal hyperplasia with multifocal ulceration and focally extensive, dermal pyogranulomatous inflammation with numerous intact and degenerate neutrophils being surrounded by epithelioid macrophages, lymphocytes and plasma cells, as well as rare eosinophils. Within the macrophages, and freely within the inflammatory infiltrate, were small (2-4μm) round, basophilic protozoal organisms. Immunohistochemistry and colourimetric in-situ hybridization were positive for amastigote forms of Leishmania spp. The species L. martiniquensis was identified by polymerase chain reaction targeting the ITS-1 gene performed with extracts from formalin-fixed and paraffin wax-embedded samples of skin lesions. L. martiniquensis causes an ulcerative pyogranulomatous dermatitis in horses with spontaneous healing. This second autochthonous case in Florida, 5 years after the first case, suggests that this parasite may have become endemic in this state.

Seroprevalence of Toxoplasma gondii in horses: A global systematic review and meta-analysis

Toxoplasmosis, one of the most common zoonoses worldwide, is caused by Toxoplasma gondii. T. gondii can infect almost all warm-blooded animals, including humans. Horses are an intermediate host of T. gondii, representing a potential risk for humans. To determine the T. gondii seroprevalence in horses worldwide, a global meta-analysis was conducted. A total of 35 publications were obtained by searching the PubMed, ScienceDirect, Chinese Web of knowledge (CNKI) and Wanfang databases. A total of 12,354 horses were assessed, of which 1580 were positive for T. gondii. The pooled overall seroprevalence of horses infected by T. gondii was 11.29%. No significant difference of T. gondii seroprevalence was observed between male and female horses. The seroprevalence of T. gondii in horses from different countries varied. Our findings suggest that toxoplasmosis is prevalent in horses worldwide. Therefore, it is necessary to implement continuous monitoring of the status of T. gondii seroprevalence in horses. Moreover, powerful regulatory measures should be implemented to prevent and control the spread of toxoplasmosis.

A candidate-SNP retrospective cohort study for fracture risk in Japanese Thoroughbred racehorses.

Fractures are medical conditions that compromise the athletic potential of horses and/or the safety of jockeys. Therefore, the reduction of fracture risk is an important horse and human welfare issue. The present study used molecular genetic approaches to determine the effect of genetic risk for fracture at four candidate SNPs spanning the myostatin (MSTN) gene on horse chromosome 18. Among the 3706 Japanese Thoroughbred racehorses, 1089 (29.4%) had experienced fractures in their athletic life, indicating the common occurrence of this injury in Thoroughbreds. In the case/control association study, fractures of the carpus (carpal bones and distal radius) were statistically associated with g.65809482T/C (P=1.17 x 10-8 ), g.65868604G/T (P=2.66 x 10-9 ), and g.66493737C/T (P=6.41 x 10-8 ). In the retrospective cohort study using 1710 racehorses born in 2000, the relative risk (RR) was highest for male horses at g.65868604G/T, based on the dominant allele risk model (RR=2.251, 95% confidence interval 1.407-3.604, P=0.00041), and for female horses at g.65868604G/T, based on the recessive allele risk model (RR=2.313, 95% confidence interval 1.380-3.877, P=0.00163). Considering the association of these SNPs with racing performance traits such as speed, these genotypes may affect the occurrence of carpus fractures in Japanese Thoroughbred racehorses as a consequence of the non-genetic influence of the genotype on the distance and/or intensity of racing and training. The genetic information presented here may contribute to the development of strategic training programs and racing plans for racehorses that improve their health and welfare.

Use of Platelet-rich Plasma in the Treatment of Desmitis of Distal Interphalangeal Joint Collateral Ligament in a Horse

Background: Platelet-rich plasma (PRP) has been increasingly used to hasten healing of tendonitis and desmitis, allowing horse athletes to go back to practicing sports in a shorter period of time. However, its use has rarely been reported in the treatment of desmitis of the collateral ligaments of the distal interphalangeal joint (CL-DIP), which is based on the use of horseshoes and rest for at least six months. This paper describes the use of PRP as an aid in the treatment of CL-DIP in a horse athlete.Case: A male Criollo horse, 450 kg, about 15-year-old, used for team roping. The animal had a month-long history of lameness, and a visual inspection revealed an increase in volume in the lateral dorsal region of the limb proximal to the coronary band of the hoof. A specific examination of the locomotive system showed Grade III, Category 5 claudication, which became evident the beginning of the exercise and ceased after a short period. A radiographic evaluation of the distal phalanx revealed no clinically relevant changes. Therefore, and in view of the location of the increased volume, an ultrasound scan was performed, which showed an image compatible with an extensive hematoma in the region underlying the perioplic corium, while the CL-DIP presented swelling with large areas of hypoechogenicity. Considering the findings of the image, the physical examination and the history of the horse, desmitis of the collateral ligaments of the distal interphalangeal joint was diagnosed. The treatment plan consisted of rest, application of a therapeutic horseshoe, and infiltration of the lesion with platelet-rich plasma (PRP). First, however, warm compresses were applied to reduce the swelling. The PRP was obtained by collecting whole blood from the external jugular vein, subjecting it to double centrifugation, and separating the supernatant blood plasma. The end product was applied to the lesion by ultrasound-guided infiltration. The horseshoe was a model with extended side bar, i.e., an egg bar horseshoe. After 15 days of PRP infiltration, another ultrasound scan was performed, which showed improved echogenicity of the ligament. The animal was discharged, and rest and the use of the horseshoe for 6 months were recommended. However, the owner expressed interest in having his horse participate in a high level team roping event, which was slated to take place two months hence. In view of this plan, rest was recommended for a further 15 days, followed by a gradual return to the exercise until the moment of the competition, which should be interrupted if the animal displayed any sign of lameness. The animal performed well in the competition, showing no loss of performance due to locomotor changes. Discussion: Locomotor disorders in the digit region are common in Creole horses, and one of the affected structures in this area is the CL-DIP. Desmitis of this ligament is characterized by acute claudication in animals without radiographic abnormalities, and can be diagnosed based on ultrasound scans. The main cause of this disorder stems from biomechanical alterations, and therefore the main treatment is the use of a therapeutic bar horseshoe on the affected side. The prognosis varies between favorable and unfavorable, and the healing time lasts on average 6 months. In view of this lengthy period of time, one of the alternatives to hasten healing is to use PRP, which is commonly used in tendonitis of the flexor tendon and suspensory ligament desmitis. Nevertheless, this technique provides variable outcomes and its application to CL-DIP remains insufficiently described. In the case reported here, its use in association with conventional treatment was effective, enabling the horse to participate in competitive events without loss of performance due to claudication.

Obstructive Urolithiasis in Horse

Background: Obstructive urinary tract disease in horses is a rare and low prevalence pathology in the species, but potentially severe. It is an emergency condition that presents variable clinical signs and depends on the anatomical location of the obstruction. The bladder calculus are the most common followed by the urethra and less commonly seen are the kidney or ureteral. The main crystalloid component of uroliths in horses is calcium carbonate. The higher prevalence of urolithiasis in male horses is justified by some anatomical differences between genders. The urethra of males is narrower and longer than that of females. The tissue injury is the most important factor for the development of uroliths in horses. Desquamation of epithelial cells, presence of leukocyte and necrotic cell debris are relevant contributors to crystal growth. Urinary stasis favors nucleation by increasing the chance of contact between crystalloid material and urinary epithelium. Once crystal growth has begun, the urine alkalinity of the equines favors the crystallization and further deposition of other components, especially calcium carbonate. Typical clinical signs of urolithiasis include tenesmus, dysuria, strangury and polaquiuria. Hematuria is often present, mainly observed after exercise and at the end of urination. In addition signs of colic are quite frequent in the acute bladder and urethral urolithiasis due to bladder distension. Upper urinary tract surgery may be technically challenging due to limited structural exposure, especially in adult horses The prognosis for horses with urolithiasis depends on the location of the urolith and the degree of renal injury that occurred.Case: This report aims to describe a rare case of obstructive urolithiasis in a 8-year-old castrated male horse with 24 h evolution. The horse was expressing signs of abdominal pain and during the transretal examination through palpation, it was possible to notice great distension and turgidity of the bladder, in addition to a high pain sensitivity to the palpation of the kidneys. Was perform urethral catheterization, but it was unproductive. The diagnosis was made through perineal ultrasonography and treated surgically by perineal urethrotomy. The animal presented an excellent evolution after being discharged after 10 days of hospitalization and did not present any complication or recurrence of the disease after one year of the procedure.Discussion: Urolithiasis in horses has a prognosis dependent on the location of the urolith and the degree of renal damage. Cases of obstructive urolithiasis in horses are rare and require prompt and appropriate intervention. Therefore, a rapid and accurate diagnosis is directly related to the success of the treatment. In the present case, the animal had characteristic clinical signs of an acute abdomen. Transrectal palpation, for evaluation of the intestinal portions, was important to diagnose an excessively distended urinary vesicle with no intestinal changes. Transcutaneous ultrasonography of the perineum allowed visualization of the calculus, and then a case of perineal urolithiasis was diagnosed. The choice for perineal urethrotomy was performed because of the ease of palpation of the calculus through the skin below the anus and because it is a non-invasive technique. The urethra was sutured to guide the cicatricial process and the urethral catheter was maintained, reducing the risks of occlusion of the urethral lumen.

A Seroepidemiological Survey of Theileria equi and Babesia caballi in Horses in Mongolia

Equine piroplasmosis caused by Theileria equi and Babesia caballi is an economically important disease with a worldwide distribution. The objective of the present study was to investigate the seroepidemiology of T. equi and B. caballi in horses reared in various Mongolian provinces. Serum samples prepared from blood collected from horses in 19 Mongolian provinces were screened for antibodies specific to T. equi and B. caballi using enzyme-linked immunosorbent assays based on recombinant forms of T. equi merozoite antigen-2 and the B. caballi 48-kDa merozoite rhoptry protein, respectively. Of 1,282 horses analyzed, 423 (33%) and 182 (14.2%) were sero-positive for T. equi and B. caballi, respectively. Additionally, 518 (40.4%) were positive for at least 1 parasite species, of which 87 (16.8%) were co-infected with both parasites. Both T. equi and B. caballi were detected in all surveyed provinces, and on a per province basis the positive rates ranged from 19.0 to 74.2% and 4.5 to 39.8%, respectively. Theileria equi- and B. caballi-positive rates were comparable between male horses (31.9 and 14.1%, respectively) and female horses (34.5 and 14.3%, respectively). However, the positive rates were higher in the >3-yr-old age group (37.7 and 15.6%, respectively) compared with the 1-3-yr-old age group (19.4 and 10.0%, respectively). These findings confirmed that T. equi and B. caballi infections are widespread among horses all over Mongolia, and that horse age is a risk factor for infection in this country. Our results will be useful for designing appropriate control measures to minimize T. equi and B. caballi infections among Mongolian horses.

Application of a laparoscopic technique for vasectomy in standing horses

This report describes a technique for standing laparoscopic vasectomy in stallions through a prospective descriptive study. A preliminary study was carried out with two experimental intact male horses and subsequently...

Motivating Signs of the Concepts “Horse” and “Loshad' / Kon'” in Cross‐Cultural Conceptual Worldviews

The paper features the concepts of «horse» and «loshad' / kon'» and their motivating signs. A concept emerges when the internal primary form of the word appears to objectify the concept in the language. According to the conducted analysis, the concepts have several motivating signs of different language actualization frequency. The most ancient and frequent originated from the Pre-Indo-European language: the name of an animal of a certain family, domesticated or wild animal; to run; cart; chariot; torrent; swift; adult male horse, stallion, gelding; device; large, coarse, healthy, (horsepower – unit of measure); cavalry; plow, harrow; earth; netherworld, hell; spark, fire; fate; to curse, to revenge, barren, mist, darkness; the spirit of cereals; spotted, pockmarked; jewel, to praise, give a loud shout; to fly; lightning; terrible, attack of illness; horse thief. The analysis revealed four signs that are common for both cultures: the name of an animal of a certain family, domesticated or wild animal; to run; adult male horse, stallion, gelding; harrow, plow; unit of measurement. The examples prove frequency and relevance of the motivating signs. Some signs currently function in the form of symbolic signs.

CONVENTIONAL AND MOLECULAR STUDY OF Babesia spp. OF NATURAL INFECTION IN DRAGGING HORSES AT SOME AREAS OF BAGHDAD CITY, IRAQ

The present study was planned to investigate equine babesiosis in dragging horses in Baghdad city, Iraq by using microscopical and molecular (PCR) techniques. 150 blood samples of horses examined for Theileria equi and Babesia caballi. 16.66% (25/150) were positive by microscopic examination. No significant difference was observed in infection rates between male and female horses and among different age groups. The result showed that PCR method has high rate of infection36% (9/25). Nine positive PCR products were sequenced and deposited in Genebank data base for first time in Iraq, phylogenic analysis demonstrated that 5 sequences belongs to T. equi (MK350319, MK346272, MK346273, MK346274 and MK36275), while 4 sequence (MK346276, MK346277, MK346278 and MK350318) belongs to B. caballi, and mounted a low genetic variation 0.035 and 0.05 respectively, among other comparison isolates. In conclusion PCR technique followed by phylogenic tree analysis a reliable methods for epidemiological, diagnosis and identification of genetic variants studies.

Horses from atypical Turkic period burials in southwest Siberia

AbstractThe article presents the results of a zooarchaeological research of two horse skeletons from atypical Turkic period burials found in the necropolis Chumysh‐Perekat (Altai Kray, Russia). The remains belong to 5 and 10–12‐year‐old male horses. Macromorphological analysis showed some dental (wear on P2, over growths of M1, and irregular wear of M1) and bone pathologies (fusion of the splint bone with metapodia, lumbar vertebrae). Their presence is associated with horse riding. The pattern of dismemberment of one of the horses and tools used to implement it was reconstructed. The authors assume that such manipulations with horse carcasses is a special modification of Turkic funeral tradition by a local Samoyed group. This reflects an early stage of spreading of these traditions to the northern periphery of the Turkic empire.

Primary Paranasal Maxillary Hematoma: Clinical Characteristics, Diagnosis and Surgical Treatment

Background: The equine paranasal sinus have a complex anatomy and large compartiments. For this reason, deseases that affect these structures may develop for long periods before the animal show any clinical signs, making it difficult to stablish a definitive diagnosis and institute an adequate treatment. Usually, maxillary hematomas reports come from progression of ethmoidal hematomas, and the descriptions of primary maxillary hematomas are rare. This study aims to report the clinical features, diagnosis and treatment of a case of a maxillary hematoma not associated with ethmoidal turbinates.Case: An 8-year-old male horse, Mangalarga Paulista, was referred to the Centro de Apoio ao Ensino e Pesquisa FMVZ-USP with history of nasal bleeding for over a year. The animal presented deformity on the right side of the face, with significant volume increase on the maxillary bone region and dull sound at percussion, in addition to great painfull sensibility when palpated. The right nare had no airflow, suggesting complete obstruction of the right nasal cavity. In order to better evaluate, endoscopic and radiographic exams were performed. At the radiographic exam, in ventrodorsal projection, it was observed an increase of volume and radiopacity, occupying the right antimer of the nasal cavity, with left nasal septum deviation. In the right dorsoventral oblique projection, it was observed the filling of the rostral and caudal maxillary sinus with the content radiopacity as previously described. At endoscopy exam of the right nasal cavity, it was observed a rounded greenish structure on the middle meatus The diagnosis of maxillary paranasal sinus cist was suggested and surgical removal, through maxillary sinusotomy was recommended. During the surgical procedure, it was noted that the structure previously observed, was not a cavitary organization filled with liquid, but a deorganized, dark and friable mass, like a hematoma. A fragment was sent to histopathological evaluation, which revealed the presence of intact eythrocytes interspersed by fibrilar eosinophilic material (fibrin). There were no indications of an infectious or neoplastic process. The diagnosis of maxillary hematoma was concluded. Forty days after admission, the patient had no surgical complications and showed adequate respiratory flow, at which point the animal was discharged.Discussion: Primary maxillary hematomas are rare on equines. Although benign, it has destructives and expansives characteristics, and for this reason, it can be confused with malignant tumor formation. It has unknown ethiology, and the clinical signs observed are diverse and non specific, which makes it hard to stablish a definitive diagnosis based only on the clinical manifestations of the animal. In this particular case presented, the diagnosis was defined from the hitophatological examination. Initially the image exams (radiography and endoscopy) were usefull to stablish differential diagnosis, as well as the extention of the sinus mass. The surgery was performed with the animal on quadrupedal position, under sedation and local anethesia, in order to dimish haemorrhage occurance during the procedure. This paper describes a primary maxillary hematoma on a horse, characterizing it as to the clinical and pathological manifestations, as well as its surgical treatment. Although rare descriptions and with non specific clinical signs, it is suggested that its occurrence is superior to that described in the literature.

Plasma concentrations at two dexmedetomidine constant rate infusions in isoflurane anaesthetized horses: a clinical study

ObjectiveTo determine dexmedetomidine plasma concentrations at two infusion rates in isoflurane anaesthetized horses and compare cardiovascular effects and anaesthetic recovery between treatments. Study designProspective, randomized, masked clinical study. AnimalsHealthy, adult, client-owned, non-food producing horses presented for castration. MethodsPremedication consisted of acepromazine, romifidine and morphine, and anaesthesia was induced with ketamine and midazolam. The horses were randomized to receive dexmedetomidine 0.5 μg kg−1 hour−1 (treatment DL, n = 7) or 1.75 μg kg−1 hour−1 (treatment DH, n = 7) for 90 minutes of isoflurane anaesthesia at an end-tidal concentration of 1.2%. Venous plasma concentrations were determined with liquid chromatography-electrospray-ionization-tandem mass spectrometry. Jugular venous and arterial blood was sampled for blood gas analysis at the start and end of the infusion. Changes in cardiovascular variables from the start to the end of the infusion, and recovery parameters were statistically compared between treatments. ResultsFourteen male horses, 2–6 years old, 325–536 kg were included. Mean ± standard deviation dexmedetomidine plasma concentrations at 30, 60 and 90 minutes with treatment DL were 0.22 ± 0.05, 0.29 ± 0.07 and 0.33 ± 0.08 ng mL−1, and with treatment DH were 0.65 ± 0.11, 0.89 ± 0.10 and 1.01 ± 0.10 ng mL−1. The 95% confidence interval for change minute−1 in dexmedetomidine plasma concentrations between 75 and 90 minutes was 0–1% for both treatments. With treatment DH, the heart rate decreased significantly more from the beginning to the end of the infusion compared to DL (p = 0.043). No other significant differences were found between treatments in cardiovascular or recovery parameters. Conclusions and clinical relevanceInfusion of dexmedetomidine in isoflurane anaesthetized horses resulted in plasma concentrations with low variation at both infusion rates, approaching stable levels after 75 minutes of infusion. No differences of clinical importance were found when comparing cardiovascular variables and quality of recovery between treatments.

Morphometric measurements and zootechnical indices of the Pantanal in race horses of different ages and gender.

The aim of this study was to perform linear measurements and assess morphometric indices of equines of the Pantanal race of different ages in the municipality of Poconé-Mato Grosso. Fifty-seven clinically healthy male and female horses between 1 and 19years of age were selected and divided into groups by sex: 41 animals males and 17 animals femeles, and age groups: group 1 (nine animals up to 12months of age), group 2 (eight animals from 12 to 24months), group 3 (15 animals from 24 to 48months), and group 4 (27 animals older than 48months). With the aid of a hypometer, the following linear measures were carried out: height at the withers and croup, and body length. The thoracic circumference and cinnamon were measured with a tape. From these measures, the following zootechnical indices were calculated: estimated weight, relationship between height at the whithers and height at the croup (RHC), dactyl thoracic (DTI), body index (BI), forming index (FI), load index 1 (LI1), load index 2 (LI2), body relative index (BRI), compactness index 1 (COI1), compactness index 2 (COI2), load index in cinnamon (LIC). In general, horses of the Pantanal breed are hipometric and longilinear; only the adult group of animals were mediolinear, with a good relationship between the withers and croup. They can be used with a saddle or take traction, with the ability to move their limbs slowing down with age. An influence of sex and age on the analyzed variables was observed.

Epidemiological characterization of Leptospira spp. infection in working horses and in an occupationally exposed population in six Colombian police stations

Introduction: Police working horses are in close contact with their managers and the general population during recreational and patrol activities, which can favor the transmission of leptospirosis among the horses and the occupationally exposed personnel. Objective. To characterize epidemiologically leptospirosis through serology, urine culture and PCR in working horses and in the occupationally exposed population in six police stations in Colombia. Materials and methods. We tested 153 castrated male horses and 123 people in six police stations in the municipalities of Manizales, Pereira, Armenia, Ibagué, Tuluá, and Cali. Three structured formats were applied and blood samples were obtained from people and horses, which were processed with the Macroscopic Agglutination Test, (MAT) for 24 serogroups. Horses were subject to a clinical examination, and urine samples were obtained for urine culture and conventional PCR. Results. The seroprevalence of human Leptospira spp. was 3.25% (n=4) while in horses it was 85% (n=130). Among the horses, serogroups Djasiman and Shermani were the most prevalent. The urine culture was positive in 64.7% (99/153) of the samples, whereas PCR analyzes were negative. A statistically significant association was found between the frequency of exiting the facilities (p=0.009) and the presence of wildlife (p=0.0051) with the infection by serogroup Shermani. Conclusion. The epidemiological characteristics of leptospirosis in horses suggest an endemic presentation of the infection and its role as reservoirs of the bacteria; however, it is necessary to elucidate the pathogenesis of the disease with complementary studies.

Evaluation of Biological Indicators of Fatigue and Muscle Damage in Arabian Horses After Race

The aim of this study was to assay changes in blood biochemical parameters that resulted from exercise-induced muscle fatigue in horses participating in the two races (1,250 and 1,400 meters). Six male Arabian horses (3 to 6 years old) were used in this study. Blood samples were collected at time intervals including 1 hour before the race, immediately after the race, 1 and 24 hours after the end of race. Catalase (CAT), superoxide dismutase, glutathione peroxidase (GPX) activities, the blood level of malondialdehyde, protein carbonyl, and total antioxidant capacity (TAC) were measured, as well as muscle damage biomarkers including aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) activities, and myoglobin were measured. The results showed that CAT activity and plasma TAC in the horse increased immediately after the race and then gradually decreased. The highest GPX activity in red blood cells was recorded 1 hour before the start of the race. Superoxide dismutase showed an incremental pattern after the race. Immediately after the race, there was a significant increase in the plasma levels of AST, which continued until 1 hour after the race. The activity of LDH and CK reached its highest value 1 hour after the race. According to our findings, it can be concluded that the horses were tired and antioxidant enzymes altered under fatigue conditions. Muscle damage biomarkers have increased, but these increases were in their natural ranges and did not indicate muscle damage in horses.

Age related and seasonal changes of plasma concentrations of insulin-like peptide 3 and testosterone from birth to early-puberty in Thoroughbred male horses

The peripheral blood concentrations of insulin-like peptide 3 (INSL3) have been detected in many mammalian species, but the level of INSL3 in horse remains unknown. The objectives were to develop a time-resolved fluorescence immunoassay (TRFIA) to detect INSL3 concentrations from horse blood as well as to determine the age-related and seasonal changes of plasma concentrations of INSL3 and testosterone from birth to early-puberty in Thoroughbred male horse (n = 11). Monthly blood sample and measurement of body weight, height, chest and cannon bone size were done from birth until 16 mo. The TRFIA and EIA were used to measure plasma concentrations of INSL3 and testosterone, respectively. An increase in mean body weight, height, chest and cannon bone size was observed throughout the study. The monthly blood sampling revealed an increase in mean plasma INSL3 concentrations up to 2 mo, followed by a decreasing and increasing pattern until the end of experiment at 16 mo. A high testosterone level was detected at birth followed by a sharp decrease to basal level within 1 mo, maintained low level up to10 mo before a gradual rise until 16 mo. In case of seasonality, there was no difference in mean plasma INSL3 concentrations between breeding (March to September) and non-breeding (October to February) seasons, whereas a higher (P < 0.001) mean plasma testosterone concentrations in the second breeding season compared to non-breeding season was observed. In age categorized group, an increase (P < 0.01) in mean plasma INSL3 concentrations was noticed at pre-puberty (1–12 mo) and early-puberty (13–16 mo) compared to birth, but a lower (P < 0.001) mean plasma testosterone concentrations was observed at pre-puberty compared to birth and early-puberty. In conclusion, a TRFIA was developed to measure INSL3 levels in horse. An increase in plasma concentrations of INSL3 and testosterone were observed with the advancement of age, whereas for testosterone a very lower level was detected at the non-breeding season than in the second breeding season after birth in Thoroughbred male horse. The INSL3 secretions seemed independent of seasonal influence, at least before puberty.

Elucidation of the biosynthetic pathways of boldenone in the equine testis

Boldenone is an anabolic-androgenic steroid that is prohibited in equine sports. Urine from the uncastrated male horse contains boldenone that is thought to be of endogenous origin and thus a threshold (‘cut-off’) concentration has been adopted internationally for free and conjugated boldenone to help distinguish cases of doping from its natural production. The testis is likely to be a source of boldenone. Qualitative analysis was performed on extracts of equine testicular homogenates (n = 3 horses) incubated non-spiked and in the presence of its potential precursors using liquid chromatography tandem mass spectrometry (LC–MS/MS) and LC high resolution mass spectrometry (LC–HRMS). Samples were analysed both underivatised and derivatised to increase the certainty of identification. In addition to previously reported endogenous steroids, analysis of non-spiked testicular tissue samples demonstrated the presence of boldenone and boldienone at trace levels in the equine testis. Incubation of homogenates with deuterium or carbon isotope labelled testosterone and androstenedione resulted in the matching stable isotope analogues of boldenone and boldienone being formed. Additionally, deuterium and carbon labelled 2-hydroxyandrostenedione was detected, raising the possibility that this steroid is a biosynthetic intermediate. In conclusion, boldenone and boldienone are naturally present in the equine testis, with the biosynthesis of these steroids arising from the conversion of testosterone and androstenedione. However, additional work employing larger numbers of animals, further enzyme kinetic experiments and pure reference standards for 2-OH androstenedione isomers would be required to better characterize the pathways involved in these transformations.

Body Dimension Factors Affecting Live Weight Estimation Accuracy of Indonesian Local-Thoroughbred Racing Horse

Study was conducted to estimate live weight of Indonesian Local-Thoroughbred racing horse using their chest girth, body length and body volume represented by chest girth and body length dimensions. Data on animal live weight (LW), body length (BL), chest girth (CG) and body volume were collected from male horses (n=188) kept by the owner club members of North Sulawesi Racing Horse. Animal body volume was calculated using cylinder volume formula with CG and BL as component factors of the formula. Data were classified on animal age basis of five groups. Regression analysis was applied for LW with all linear body measurements. Age significantly influenced all body measurements. Simple regression can be recommended to predict live weight of this animal based on body volume with their average age groups as follows: Live weight ( Y in kg unit) = - 0.002+1.16 body volume (dm 3 ) with determination coefficient (R 2 ) of 0.98. The multiple regression can also be recommended to estimate accurately live weight of this animal at age average groups as follows: Live weight ( Y in kg unit) = - 0.11 - 2.74 chest girth ( X 1 in cm unit) + 4.92 body length ( X 2 in cm unit) with R 2 of 0.98.

Effect of Diminazene aceturate treatment on some cardiovascular parameters and antioxidant status of apparently healthy horses

IntroductionApart from being a widely used antiprotozoal drug in many parts of Africa, Diminazene aceturate (DIZE), has been shown to have beneficial effects in experimental murine models of hypertension, pulmonary hypertension, myocardial infarction, stroke, atherosclerosis, type 1 diabetes, and eye disease. In this study, we investigated the effect of diminazene aceturate treatment after a single intramuscular administration on some cardiovascular parameters and antioxidant status in apparently healthy Nigerian horses.Materials and methodsTen male horses were divided into two groups comprising 5 horses each. Group A was the control group with no drug administered. Group B was treated with DIZE at 3.5 mg/kg, single dose. Baseline data were collected before the commencement of the experiment and thereafter, post‐administration at 0hrs, 24hrs, 48hrs and 96hrs. Base apex electrocardiogram was recorded using a computer ECG machine while oscillometric blood pressure measurement was recorded using a veterinary blood pressure monitor. Markers of oxidative stress were determined in the serumResultSingle intramuscular treatment caused a significant (p&lt;0.05) increase in the systolic, diastolic and mean arterial blood pressure values when compared with the controls. From the electrocardiogram, sinus rhythm was recorded in both groups however, significant (p&lt;0.05) increase in heart rate, p‐wave duration, QRS complex duration and QTc were observed in the treated group when compared with the control. Oxidative stress markers (malondialdehyde and hydrogen peroxide) significantly (p&lt;0.05) increased while antioxidant enzymes (catalase, glutathione peroxidase and glutathione) were decreased when compared to the control.ConclusionThis study indicates that the use of DIZE in horses should be with great caution because of the associated cardiovascular physiological alterations, reduction in activities of antioxidant enzymes and increase in markers of oxidative stress.Support or Funding InformationNoneThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Genetic Disorders Affecting Equine Blood Cells and Coagulation Factors: A-State-of-The-Art Review

Genetic diseases that affect blood cells and clotting factors in the horse are uncommon. Unfortunately, the prognosis is reserved, because the treatment in many cases is only symptomatic and when it fails, euthanasia of the patient is the only viable option. The detection of carriers is of pivotal importance in order to prevent the spread of these disorders in the equine population. This manuscript reviews the current state of knowledge of genetic diseases that affect red blood cells, leukocytes, platelets and clotting factors in the horse. The genetic diseases that affect equine red blood cells are defects in the activity of enzymes and cofactors involved in erythrocytes metabolism, such as glucose 6 phosphate dehydrogenase, flavin adenine dinucleotide, glutathione reductase and glutathione. Therefore, their deficiency triggers methemoglobinemia and hemolytic anemia. Genetic disorders affecting granulocytes are rare in horses, but a Pelget-Hüet anomaly has been reported. Primary immunodeficiencies described in horses and arising from defects in the immune system are severe combined immunodeficiency, X-linked agammaglobulinemia and Fell pony immunodeficiency syndrome. Because of the immunodeficiency, foals usually develop fatal infections during the first weeks or months of life, caused for opportunistic organisms. Prognosis of these animals is poor. The most common genetic defect of platelet is Glanzmann thrombasthenia, which results in prolonged bleeding time and hematoma formation. Spontaneous bleeding or impaired hemostasis after trauma or surgery are clinical findings in types 1 and 2 von Willebrand disease. Hemophilia A, resulting from a decreased activity of coagulation factor VIII has also been described in male horses of different breeds, being the most common genetic disorder affecting coagulation factor in the horse. Prekallikrein deficit, although described in some horses, is a rare genetic coagulation factor deficiency.