Morphology of the brain base arteries of the giant anteater (Myrmecophaga tridactyla)

This study aimed to describe the brain base arteries of the Myrmecophaga tridactyla using ten cadavers of adults from this species, including five male and five female specimens. The arterial vascular bed was perfused via the thoracic aorta with a dyed natural latex solution, and the animals were fixed and preserved with a 10% formaldehyde buffered solution. The encephala were removed, and their vessels dissected. Basilar artery formation occurred by anastomosis of the thick ventral spinal artery with vertebral arteries. The basilar artery formed two arterial islands and gave bulbar and pontine branches, and cranial, middle, and caudal cerebellar arteries and ended by forking into its terminal branches, the caudal communicating arteries. The blood supply of the encephalon derived solely from the vertebrobasilar system, and the arterial circle of the brain was closed caudally and rostrally. The absence of participation of internal carotid arteries in encephalon irrigation, the island formations by the basilar artery, and the fusiform shape of the arterial circle of the brain are peculiar characteristics of the vascular anatomy of the brain base of M. tridactyla.

Caracterização morfométrica do pênis e prepúcio de touros das raças Nelore e Gir / Morphometric characterization of the penis and prepuce of Nelore and Gir bulls

O objetivo deste trabalho foi caracterizar alguns aspectos morfométricos do pênis e prepúcio de touros das raças Nelore e Gir, estabelecendo as correlações destes parâmetros com outras medidas corporais. O protocolo experimental foi dividido em duas etapas, sendo que na primeira foram selecionados 40 touros, 20 da raça Nelore e 20 da raça Gir, com idade de 30 a 38 meses e peso entre 382 e 468 Kg. Após o abate dos animais em frigorífico, foram coletadas peças de pênis para dissecação e morfometria. Na segunda etapa, foram selecionados 43 touros, 23 da raça Nelore e 20 da raça Gir, com idade de 60 a 96 meses e peso entre 890 a 1120 Kg, provenientes de centrais de coleta de sêmen, para mensuração do peso e comprimento corporal, comprimento da garupa, perímetro torácico, altura anterior e posterior, menor perímetro do metacarpo esquerdo e do metatarso esquerdo, comprimento do prepúcio, menor distância do óstio prepucial à parede do abdome e perímetro do óstio prepucial. As medidas obtidas foram submetidas a teste de correlação linear. O comprimento médio do pênis e prepúcio de touros da raça Nelore foi de 71,96 cm e 52,4 cm, respectivamente e nos touros da raça Gir de 75,73 cm e 57 cm, respectivamente. Dentre as correlações efetuadas, destacam-se duas positivas; uma baixa entre o comprimento corporal e comprimento prepucial (r = 0,31, p < 0,05) e outra média entre a massa corporal e o comprimento prepucial (r = 0,66, p < 0,05). Os resultados deste estudo poderão contribuir para se estabelecer o padrão destas medidas nas raças Nelore e Gir, além de indicar as correlações com outras medidas corporais que podem ser empregadas para proceder a seleção genética de touros para a reprodução.

The aim of this study was to characterize some morphometric aspects of the penis and prepuce of Nelore and Gir bulls establishing the correlations between these parameters and other body measures. The experimental protocol was divided into two stages, being that in the first stage it was selected 40 animals, 20 Nelore and 20 Gir bulls, aged between 30 to 38 months and weighing between 382 and 486 kg. After the killing of the animals in the slaughterhouse, it was collected pieces of penis for penile dissection and morphometry. In the second stage, were selected 23 Nelore and 20 Gir bulls aged between 60 to 96 months and weighing between 890 and 1120 kg. The animals were obtained from semen collection centrals and were submitted to measurement of body mass and length, rump length, thoracic perimeter, anterior and posterior height, the lower perimeter of the left metacarpal and metatarsal, length of the prepuce, the shortest distance from preputial ostium to abdominal wall and the preputial ostium perimeter. The measures obtained were subjected to linear correlation test. The average length of the penis and prepuce of Nelore bulls were 71.96 cm and 52.4 cm respectively and in the Gir bulls were 75.73 cm and 57 cm respectively. Two positive correlations stand out among the analysis performed, the low correlation between body and preputial length (r = 0,31, p < 0,05) and mean correlation between body mass and preputial length (r = 0,66, p < 0,05). The results of this study could contribute to establish the pattern of these measures in the Nelore and Gir races and indicate the correlations with other body measures that can be considered to perform the genetic selection of bulls for breeding.