A.P. Marques Júnior

Experimental ischemia and reperfusion in equine small colon

The effects of ischemia and reperfusion were studied in the small colon of 12 horses. Under general anesthesia, arterial pressure and arterial hemoglobin oxygen saturation values were maintained constant and within the normal physiological range. After celiotomy, the small colon was exposed and three segments were demarcated. Total arterial venous ischemia was induced in two segments during 90 (group A) and 180 (group B) minutes. The third segment was the control group. Full-thickness biopsy specimens, for histopathology, were obtained at the end of the ischemia periods and at 90 (groups A and B) and 180 minutes (group A) of reperfusion. The mucosa and the submucosa were evaluated by semiquantitative morphological assessment such as epithelial detachment, edema and hemorrhage, and by quantitative morphological assessment such as percentual depth of mucosal loss (ML) and mucosal crypt:interstitium ratio (C:I). After ischemia, lesions such as ML, C:I, epithelial detachment and mucosal edema were more intense in group B when compared to group A. In both groups after reperfusion there were significant increases in ML, C:I, epithelial detachment and submucosal edema. The results showed aggravation of the mucosal lesions in the reperfusion period in equine small colon, and the model was considered adequate for experimental purposes.

Puberdade em touros Nelore criados em pasto no Brasil: características corporais, testiculares e seminais e de índice de capacidade andrológica por pontos

Twenty three 10-months-old Nellore bulls, raised under pasture conditions in Brazil, were used to study puberty. Monthly measurement of scrotal circumference and testicular width and length were recorded. Semen was collected by eletroejaculation and evaluated according to physical and morphological aspects. Penile and prepuce detachment percentages were also evaluated. The ages of the presence of first spermatozoa in the ejaculate (ISEM1), first motile spermatozoa in the ejaculate (ISEM2), seminal puberty (IDPUB) and detachment between penile and prepuce (IDPPRE) were calculated. Scores of breeding soundness were measured. ISEM1, ISEM2, IDPUB and IDPPRE were 13.1±2.2, 13.6±2.3, 14.8±1.8 and 18.1±1.9 months, respectively. At 16 months of age, the animals presented 91.4%, 82.6% and 73.9% with ISEM1, ISEM2 and IDPUB reached, respectively. High positive correlation were observed between age and corporal and testicular growth or seminal physical aspects. Negative correlation was verified between age and spermatic defects. High negative correlation was observed between age and score of scrotal circumference at puberty (-0.7;7 P<0.001). Precocious puberty was observed before 15 months of age. From ISEM1 to IDPUB, 51 days were elapsed. Young bulls with larger testicles reached puberty earlier.

Placental maturation and expulsion in Holstein and Nelore cows

Morphological changes in the placenta at periparturition and the involvement of apoptosis controlling cell populations in the placentome were evaluated in Holstein and Nelore cows. Twenty-two Holstein cows at the end of gestation with normal non-induced parturition (group I) and 10 Holstein cows with induced parturition (group II) were used in this study. In addition, groups III and IV were constituted by 10 Nelore cows at the end of gestation with normal non-induced parturition and 21 Nelore cows with induced parturition, respectivelly. Binucleate trophoblastic cells, epithelial caruncular cells and apoptotic bodies were quantified by light microscopy. Apoptosis was further evaluated by transmission electron microscopy, ELISA and DNA electrophoresis in agarose gel. The number of caruncular epithelial cells did not vary between breeds with normal or induced parturition. The number of binucleate cells was significantly different between Holstein and Nelore cows with normal non-induced parturition (groups I vs. III), but their numbers were not significantly different between breeds when parturition was induced. In cows with normal non-induced parturition, the intensity of apoptosis, as assessed by morphometric analysis and ELISA, was significantly higher in group I when compared to group III. However, no difference in the intensity of apoptosis was found between groups II and IV. Characteristic apoptotic ladder pattern of DNA fragmentation was detected by agarose gel electrophoresis. Ultra-structural features of apoptosis in maternal and fetal epithelium as well as capillary vascular endothelium were identified by transmission electron microscopy. In conclusion, in Nelore placental maturation occurs precociously when compared to Holstein. In both breeds, apoptosis is an active physiological event that seems to be required for maturation and normal post-partum release of the placenta.

Efeito da hidrocortisona sobre a lesão de reperfusão e reparação da mucosa após isquemia venosa experimental no jejuno de eqüinos

In order to evaluate the effect of hydrocortisone sodium succinate (HSS) for treatment of intestinal ischemia-reperfusion, 12 halothane-anesthetized horses were subjected to both venous and arteriovenous ischemia of the jejunum. After one hour of ischemia, HSS (4.0 mg/kg/IV) was administered to six animals (T group). The other six horses received saline (NT group). Biopsy specimens were obtained after one and two hours of ischemia, and one, two and 12 hours after reperfusion. These samples were evaluated to assess the degree of mucosal damage and infiltration of neutrophils, hemorrhage, and edema. The scores for neutrophil infiltration, edema and hemorrhage did not differ between T and NT groups in both models of ischemia. However, in the jejunum subjected to venous ischemia, the scores for mucosal lesion increased significantly (P<0.05) after two hours of reperfusion only in the NT group, indicating that HSS prevented reperfusion injury. The scores for mucosal damage were equivalent after 12 hours of reperfusion following arteriovenous ischemia in T and NT groups. In contrast, mucosal lesion due to venous ischemia were more severe in the NT group (P<0.01), indicating that intestinal repair was stimulated by HSS. These results indicate that HSS may be used as an adjuvant for treatment of intestinal isquemia and reperfusion lesions in the horse.

Serum concentration of thyroid hormones in crioula lanada serrana ewes in gestation and lactation

Os efeitos da gestacao e lactacao sobre a dinâmica dos hormonios tireoidianos triiodotironina (T3) e tiroxina (T4) foram avaliados em ovelhas Crioula Lanada Serrana na regiao do Planalto Serrano Catarinense. Para avaliar os efeitos da gestacao, foram utilizadas vinte e quatro ovelhas distribuidas aleatoriamente em dois grupos. O grupo I foi formado por 12 ovelhas gestantes e o grupo controle por 12 ovelhas nao gestantes (grupo II). Os efeitos da lactacao foram avaliados nas mesmas ovelhas do grupo I apos a paricao (LE) e no grupo controle (NL). Foram colhidas amostras sanguineas no primeiro, segundo e terceiro terco da gestacao, ao parto e aos 30, 60 e 90 dias de lactacao. As concentracoes de T3 e T4 foram determinadas por radioimunoensaio (RIA). As ovelhas gestantes apresentaram concen-tracoes sericas de T3 e T4 inferiores aquelas nao gestantes. Ao parto nao houve diferenca significativa nas concentracoes de T3 entre os grupos I e II (p>0,05). Durante a lactacao as concentracoes de T3 foram menores (p£0,05) para LE que para NL. No momento do parto, as concentracoes de T3 foram maiores (p£0.05) do que aquelas observadas no periodo de lactacao e as concentracoes de T4 em LE, nao diferiram de NL. Durante a lactacao as concentracoes de T4 de LE foram menores (p£0,05) do que em NL. Os resultados deste estudo demonstraram que a gestacao causa variacao nas concentracoes sericas de T3 e T4 que, no momento do parto sao similares aquelas observadas em ovelhas nao gestantes. A lactacao causa diminuicao nas concentracoes de T3 e T4 em ovelhas Crioula Lanada Serrana.

Pré-tratamento com somatotropina bovina (rbST) na superovulação de doadoras da raça Holandesa

ABSTRACT The use of recombinant bovine somatotropin (rbST) in superovulated Holstein donors to increase the number and quality of the embryos was studied. Forty cows were randomly allotted into three groups: control (n=15), treated with 250mg rbST (n=11) and treated with 500mg rbST (n=14) on the 6 th day of the oestrous cycle. On the 10 th day after estrus the donors were submitted to a superovulatory treatment with 360mg of FSH in decreasing doses, twice-a-day, with 12 hours interval. Along with the 7 th application of FSH, 0.5mg of cloprostenol was injected and the donors were inseminated 12, 20 and 28 hours after the onset of estrus. Embryos were collected non-surgically on the 7 th day after the 1 st insemination. The use of 250 or 500mg of rbST increased (P<0.05) the percentage of viable embryos, but did not alter the recipient pregnancy rate. Keywords: embryo, pregnancy rate, somatotropin Recebido para publicacao, em 26 de abril de 2004 Recebido para publicacao, apos modificacoes, em 13 de outubro de 2004 *Autor para correspondencia (

Utilização de hidrocortisona em eqüinos submetidos a isquemia e reperfusão no jejuno e suas conseqüências sobre o cório laminar

To evaluate whether hydrocortisone sodium succinate (HSS) aggravates lesions in the laminar tissue secondary to intestinal ischemia and reperfusion (IR), two segments of the jejunum were isolated in 12 halothane-anesthetized horses, and total ischemia was induced on them. Three other horses were used as controls. One hour after the onset of the ischemia, HSS (4.0mg/kg) was administered intravenously to six animals (T group) and saline to the others (NT group). After two hours of ischemia and two hours of reperfusion the abdomen was closed and the horses were allowed to recover from anesthesia. After 12 hours of reperfusion the horses were euthanatized and biopsy specimens were taken from the laminar tissue and the lesions were evaluated and scored. No significant differences between T (0.41) and NT (0.54) groups for laminar lesion scores were observed. The results indicate that HSS did not produce harmful effects in the laminar tissue, suggesting that the occurrence of undesirable effects in the digit are not a limiting factor for using this drug to treat equine patients with acute abdomen.

Effect of deslorelin on the induction of estrus in anestrous bitches

The efficacy of one or multiple doses of an injectable formulation of deslorelin (a GnRH agonist) was evaluated to induce estrus in anestrous bitches. Thirteen animals composed three groups: group 1 (n=5, single IM injection of 2mg deslorelin), group 2 (n=5, four IM injections of 2mg deslorelin in alternate days), and control group (n=3, four IM saline injections in alternate days). Daily clinical evaluations, sexual behavior, vaginal cytology, plasma progesterone concentration, ovaryhysterectomy and macroscopic evaluation of the uterus and ovaries were done. In group 1, none of the bitches showed signs of estrus, while two developed clinical signs and vaginal cytology of proestrus. In group 2, all animals presented proestrus, four presented estrus, and three ovulated; resulting in a functional corpus luteum and high progesterone concentration until day 25 of diestrus, when ovaryhysterectomy was performed. The duration of the stages of deslorelin induced cycles and the progesterone profile were similar to those described in the literature, and no side effects were observed. In conclusion, injectable formulation of deslorelin in multiple injections was effective to induce fertile estrus in anestrous bitches.

Perfil bioquímico sorológico de bovinos inoculados experimentalmente com veneno crotálico iodado livre e iodado incorporado em liposomas

It was studied the activity of the Crotalus venom detoxified encapsulated in lipossomes or non-encapsulated by the method of controlled iodination on the biochemical profile of bovines. Eleven 18-months-old female bovines, weighting 160kg in average were used in this study. Groups of five animals were inoculated intramuscularly with a dose of 0,03mg/kg with either the detoxified non-encapsulated venom or the detoxified encapsulated venom. One control animal received the same dose of non detoxified venom by the same route. No significant differences were observed between the study groups for the parameters of total protein, urea and creatinine. Differences were observed for creatine phosfokinase at times TO and T12 for the group treated with the iodinated venom encapsulated in liposomes. The detoxification process abolished the activity of the venom in the encapsulated or nonencapsulated form on the biochemical parameters and renal activity of bovine.

Efeito da pré-estimulação ovariana sobre características de oócitos após punção folicular em bovinos

The aim of this study was to evaluate the effects of ovarian pre-stimulation with FSH and active immunization against swine inhibin on the number and quality of oocytes recovered by follicular puncture. Pluriparous, non-lactating Gir cows (n=14) were distributed as: TI - pre-treatment with 250 IU of FSH (n=4), TII - active immunization against swine inhibin (n=4) and TIII - not treated (n=6; control group). All animals had their ovarian follicles above three millimeters in diameter aspirated once a week during 10 consecutive weeks. The TI presented an increase in total follicular population (P<0.05) and in the number of punctured follicles (P<0.001), but reduced recovery rate when compared to treatments II and III (68.8% vs. 78.4% and 76.3%, respectively; P<0.01). The TII did not affect the main ovarian characteristics, except for an increase in the number of medium follicles (P<0.01). Treatment I yielded a higher percentage of viable oocytes (77.2% vs. 69.8%; P<0.05) and oocytes Grade I (19.8% vs. 11.6%; P<0.001) than TIII. Both treatments I and II resulted in reduction of the percentage of degenerated oocytes (16.4% and 16.8% vs. 22.3%; P<0.05). Ovarian pre-stimulation with FSH was the most consistent treatment for increasing quality of oocytes recovered from Zebu cattle.