The aims of this study were: 1) to compare the tape weight and associated weight-estimation formula to evaluate weight gain in pregnant mares, and 2) to develop a mathematical model to estimate the weight of pregnant mares using body measurements. Thirty-four criollo-type mares were evaluated every two weeks during the middle and late pregnancy. The mares were weighed on a livestock scale, and we estimated body weight using tape weights and an associated body-weight estimation formula. Also, heart-girth circumference (heartgirth) and abdominal circumference were measured; the latter at the 12th intercostal space (12th ICS) and 18th rib (18th Rib), to use in a mathematical model to estimate the weight of pregnant mares. Observations were divided into three periods of pregnancy: 5th to 7 h month, 7th to 9 h month, and 9th to 11th month. Mares in late pregnancy showed an increase in actual weight and an increase in 12th ICS and 18th Rib measurements. Tape weight and body-weight estimation formula underestimated the weight of pregnant mares. However, the regression model using heart-girth circumference, 12th ICS, and 18th Rib measurements showed high correlation (r2 = 0.87, P<0.001) with actual weight. Finally, the alternative methods usually used in horses are not accurate to estimate body weight in pregnant mares. In conclusion, the regression model Y=-540.143 + (heartgirth x 3.068) + (12th ICS x 1.278) + (18th Rib x 0.944) can be used to estimate body weight in pregnant mares from the 5th to 11th months of pregnancy.

RESUMO Este trabalho investigou a influência da adiposidade em éguas Crioulas gestantes sobre o peso e o acúmulo de gordura de seus potros do nascimento aos quatro meses de vida. Foram avaliadas 28 éguas Crioulas no terço final de gestação, divididas em dois grupos (normais e obesas) quanto ao peso, à circunferência de pescoço, à altura da crista do pescoço e à gordura subcutânea na base da cauda, bem como quanto à relação dessas medidas com as de seus potros, do parto aos 120 dias de idade. Os filhos de éguas obesas apresentaram maior deposição de gordura na base da cauda, no segundo mês (P<0,05), e na crista do pescoço (P=0,0022), no quarto mês de idade. Houve correlação positiva da altura da crista do pescoço da égua com o peso dos potros ao nascer (P=0,01; r= 0,54) e do peso corporal das éguas com gordura na base da cauda dos potros ao nascimento (P=0,03; r=0,49), além de forte associação entre gordura na base da cauda das éguas obesas com essa medida nos seus potros aos quatro meses (P=0,01; r=0,71). Essa diferença entre os grupos de potros quanto à adiposidade sugere que filhos de éguas obesas são mais propensos a acumular mais gordura já nos primeiros meses de vida.

In this preliminary study, a new equine platelet-rich plasma (PRP) cryopreservation protocol was evaluated. PRP was obtained by a double centrifugation technique of whole blood collected from 8 adult healthy ponies. A fresh sample of PRP was analyzed for total platelet count, mean platelet volume (MPV), and platelet morphology. Upon morphological evaluation, 200 platelets were counted using a differential interference contrast microscope with a 40x phase objective and classified as activated (with pseudopodia), inactivated (normal discoid shape), or uncertain state (spherical shape, without pseudopodia). Two other PRP samples, one containing DMSO as a cryoprotectant and the other without DMSO, were stored in a mechanical freezer at -80ºC. After 14 days, the frozen samples were thawed and submitted to the same analysis as described above. The fresh PRP showed a platelet count of 830 (±95.3) x10 3 µL -1 , an MPV of 5.2 (±0.07) fL, and composed of 4% activated platelets. There was no significant difference in platelet count, MPV, and activated platelets between fresh and 6% DMSO frozen PRP samples (617.9±65.5x10 3 µL -1 ; 5.3±0.06fL; 9.5%) (p>0.05). On the other hand, samples frozen without DMSO showed a significantly lower platelet count (519.6±66.1x10 3 µL -1 ), higher MPV (5.7±0.08fL), and more activated platelets (13.9%) than the other groups (p<0.05).The 6% DMSO was able to preserve platelet morphology in PRP stored at -80 o C for 14 days, but studies on platelet function of thawed PRP are still needed. Key words: Platelets. Storage. Equine. Dmso. ResumoNeste estudo preliminar, um novo protocolo de criopreservação de plasma rico em plaquetas (PRP) de equinos foi avaliado. O PRP foi obtido através de dupla centrifugação do sangue total coletado de oito pôneis clinicamente saudáveis. Uma amostra de PRP fresco foi analisada quanto ao número total de plaquetas, volume plaquetário médio (VPM) e morfologia plaquetária. Na avaliação morfológica 200 plaquetas foram contadas utilizando um microscópio com contraste de fase com objetiva de 40x e classificadas como ativadas (com pseudópodes), inativas (forma discóide normal) ou estado incerto (forma esférica, mas sem peseudópodes). Duas outras amostras de PRP foram armazenadas em um freezer mecânico a -80 o C, uma contendo dimetil sulfóxido (DMSO) como crioprotetor e outra sem 3 µL -1 ), maior VPM (5,7±0,08fL) e mais plaquetas ativadas (13,9%) do que os outros grupos (p<0,05). DMSO a 6% foi capaz de preservar a morfologia plaquetária no PRP armazenado a -80 o C durante 14 dias, mas estudos a respeito da função plaquetária ainda não necessários. Palavras-chave: Plaquetas. Armazenamento. Equino. Dmso.

Background: Aneurysm is a vascular disease that causes the partial rupture of arteries and veins and subsequent blood leakage due to the weakening of the vessels elastic middle layer. Venous aneurysms in horses are rare, but the arterial aneurysms are commonly reported. The aim of this paper is to report a rare occurrence of jugular external aneurysm in a horse and propose the inclusion this disease as a differential diagnosis, both because it is rare in this specie and invariably fatal. The medical examination showed a firm well-defined mass, painless, nonpulsatile on palpation and with no changed in the local temperature.Case: The horse was referred to the Veterinarian Hospital of the Federal University of Pelotas (UFPel, RS-Brazil. It was a male, Crioulo breed, 10 years old, used as stallion. The owner reported a swelling in the pectoral region that occurred after a trauma episode that had gradually grown for two years. The patient was clinically stable, and would undergo surgery extirpation for aesthetic matters. Clinical examination showed the swelling was circumscribed and centralized and it presented about 20 centimeters in diameter. The ultrasound of the pectoral area showed an anechoic structure with hyperechoic spots inside limited by an hyperechoic layer similar to a fibrous capsule. Presumptive diagnostics were of: hematoma, subcutaneous abscess, neoplasia, and possible vascular involvement. The use of conventional ultrasound was not enough to set the diagnosis, and the patient was referred to surgical exploration, where the procedures of isolation and anastomosis were performed, however rupture occurred and the patient died. Necropsy revealed sacculation of the ventral region of the neck next to the entrance of the thorax, and the involvement of the external right jugular vein, being the adjacent muscle tissue not involved. Histopathological evaluation showed intense proliferation of sub-endothelial fibrous tissue which infiltrated the tunica media and adventitia and a mild inflammatory infiltrate of lymphocytes and histiocytes, which was diagnosed as an aneurysm of the right external jugular vein.Discussion: The reported patient had a venous aneurysm located superficially, which may have contributed to the absence of symptoms. The ultrasound is a diagnostic method available to most veterinarians nowadays, mainly in the countryside. However, when it is used in the diagnosis of an aneurysm it displays a dilatation with anechoic content, which is com­mon to several other skin diseases. A similar ultrasound image was observed in the case reported, but the diagnosis was difficult because the aneurysm presented intense proliferation of fibrous tissue infiltrated in the media and adventitia of the vascular wall, similar to a capsule of fibrous tissue, which lead to the presumptive diagnostics of hematoma, abscess and neoplasia, with possible vascular involvement. The options for the treatment of the aneurysms consider the location, size and extent of them and it determines the choice between clinical observation and surgery. In veterinary medicine it is difficult to keep the animals still and in the case of a horse, any movement can lead to the spontaneous rupture of the aneurism. Considering the risk of spontaneous rupture and hemorrhage, the surgical resolution, even if risky, emerges as the most suitable treatment. Venous aneurysms although rare, need to be included as a differential diagnosis in skin diseases along with increased volume, as hematomas, abscesses and tumors. The prognosis, however, is poor because of the surgical limitations and risks of imminent rupture in the clinical treatment.Keywords: venous aneurysm, differential diagnosis, equine.

Background: Arterial rupture associated with pregnancy is an important cause of fatal hemorrhage in pregnant mares, regardless breeds and age. Such hemorrhagic events lead to blood loss into the abdomen, broad ligament and uterus and the broad ligament hematoma occurs as a consequence of arterial rupture. Although the rupture of the uterine artery is commonly caused by hemorrhage, there are few studies regarding this condition. Therefore, the aim of this study was to describe a case of rupture of the utero-ovarian artery, with broad ligament hematoma and intramural uterine hematoma in a Thoroughbred mare, emphasizing the predisposing factors and the diagnosis process.Case: A 13-year-old Thoroughbred mare, with nine parturition, was attended with abdominal pain after foaling. The mare had an eutocic delivery, however the foal was a big one to the race, with high of 1,02 m and weight of 68 kg. The animal arrived at the Veterinary Clinical Hospital 48 h after delivery, with abdominal pain, pale mucous membranes, heart rate slightly increased. The trans-rectal palpation revealed the presence of a solid mass in the left horn region, and it was painful to the touch. The ultrasonography evaluation of the mass showed a heterogeneous texture with a hypoechoic central area, which reinforced the clinical suspicion of a hematoma in the broad ligament and a uterine intramural hematoma. The animal did not respond to analgesic therapy, which resulted in shock and consequently death. Necropsy revealed free blood in the abdominal cavity and the uterine wall with swollen hematoma extended to the left broad ligament. It also showed the presence of a hematoma along the uterine wall, from the uterine body region to the ovarian insertion. Histological evaluation did not show significant changes in the arterial wall, and it revealed the formation of intramural hematoma thorough all extension of the left uterine horn, confirming the suspicion of rupture in the utero-ovarian artery and hematoma on the broad ligament and uterine intramural hematoma in the left horn.Discussion: Rupture of uterine arteries can occur at any age, although it is often observe in old mares, possibly because of the vascular degenerative features observed in these animals. In addition, multiparous mares are more prone to it because multiple births can favour damages in vascular system. The clinical assessment showed characteristics compatible with postpartum hemorrhage. A thorough trans-rectal evaluation revealed a mass in the left horn. The ultrasonography evaluation from the mass showed echogenic characteristics consistent with those described for broad ligament hematoma and uterineintramural hematoma in the left horn. The clinical suspicion, rupture of the uterine artery, with formation of a hematoma in the broad ligament and uterine intramural hematoma, was based upon the history, clinical signs and laboratory tests, especially the characteristics revealed by the ultrasound from the mass in left horn. Necropsy showed the rupture of the utero-ovarian artery. Lesions are usually observed on the right uterine artery due to the displacement of the uterus to the left abdominal wall by the cecum, which results in an increased tension on the right broad ligament. However, in this case the rupture was associated to the gravid horn. The rupture of the utero-ovarian artery is a major cause of hemorrhage in the postpartum and this can form a hematoma in the broad ligament and uterine intramural hematoma. In conclusion, the mare from this study showed as the predisposing factors the age and the number of parturition. Clinical sings are very similar to others abdominal pain conditions, being the exams essential to diagnosis, especially ultrasonography. Rupture of the utero-ovarian artery is an emergency with unfavorable prognosis.Keywords: artery, utero-ovarian, mare, hemorrhage.