O objetivo deste estudo foi o de medir in vivo as dimensões da próstata, pelo exame ultra-sonográfico, de cães de diferentes tamanhos, com idade entre 1 e 5 anos. Foram realizados exames em 47 cães, sem processos patológicos aparentes. Os pacientes foram divididos em dois grupos de acordo com a idade, Grupo 1: cães entre 12 e 30 meses e Grupo 2: cães entre 31 e 60 meses. Cada grupo foi subdividido em três subgrupos de acordo com o peso. Subgrupos 1 e 4 com animais até 10kg, Subgrupos 2 e 5 com animais entre 11 e 25kg e Subgrupos 3 e 6 com animais acima de 25kg sendo que os Subgrupos 1 a 3 pertencem ao Grupo 1 e os Subgrupos 4 a 6 pertencem ao Grupo 2. As imagens em corte longitudinal e transversal permitiram a observação da próstata, localizada caudalmente à bexiga urinária, de formato arredondado, de contornos regulares e definidos e de ecogenicidade maior que a do baço. Comprimento e altura foram mensurados no plano longitudinal, já a largura foi medida no plano transversal. O Subgrupo 1 apresentou medidas prostáticas de comprimento: 1,19 (±0,16cm); de altura: 1,17 (±0,2cm) e de largura: 1,41 (±0,24cm), valores menores que os obtidos no Subgrupo 4 que apresentou comprimento: 2,14 (±0,13cm); altura: 2,12 (±0,16cm) e largura de 2,59 (±0,21cm). O Subgrupo 2 apresentou valores prostáticos de comprimento: 2,17 (±0,11cm); de altura: 2,04 (±0,15cm) e de largura: 2,64 (±0,13cm), valores menores que os obtidos no Subgrupo 5 que apresentou comprimento: 2,81 (±0,44cm); altura 3,73: (±0,37cm) e largura de 3,29 (±0,38cm). O Subgrupo 3 apresentou valores prostáticos de comprimento 3,09 (±0,21cm); de altura: 2,93 (±0,21cm) e de largura: 3,63 (±0,19cm), valores menores que os obtidos no Subgrupo 6 que apresentou comprimento: 3,47 (±0,31cm); altura: 3,35 (±0,35cm) e largura de 4,03 (±0,28cm). A correlação foi forte entre os valores prostáticos determinados e a massa corpórea dos cães estudados.

The aim of this study was ultrasonographically assess the prostatic dimensions in dogs of different sizes, aging from 1 to 5 years-old. Forty-seven examinations were done, in dogs with no clinical diseases. The patients were divided into two groups according to their ages, such as: Group 1 - from 12 to 30 months-old and Group 2 ? from 31 to 60 months-old. Each group was divided into 3 other groups according to their weight. Subgroup 1 and 4: up to 10 Kg, subgroup 2 and 5: from 11 to 25 Kg and subgroups 3 and 6: over 25 Kg (subgroups 1 to 3 were inserted in Group 1 and subgroups 4 to 6 were inserted in Group 2). The sagittal and transverse planes on ultrasonographic examination provided the entire visualization of the prostate, which was round to normal-shaped, lies caudally to the urinary bladder, with smooth margins and hyperechoic to the spleen. Their length and height were measured on sagittal plane and the width was measured on transverse plane. Regarding the subgroup 1, the mean prostatic length was 1,19 cm (± 0,16 cm), the mean prostatic height was 1,17 cm (± 0,2 cm) and the mean prostatic width was 1,41 cm (± 0,24 cm), and these measurements showed to be shorter than the ones from subgroup 4, such as 2,14 cm (± 0,13) as for the mean length, 2,12 cm (± 0,16 cm) as for the mean height and finally 2,59 cm (± 0,21 cm) as for the mean width. Regarding the subgroup 2, the mean prostatic length was 2,17 cm (± 0,11), the mean height was 2,04 (± 0,15 cm) and the mean width was 2,64 cm (± 0,13), and these measurements showed to be shorter than the ones from subgroup 5, such as 2,81 cm (± 0,44) as for mean length, 3,73 cm (± 0,37 cm) as for the mean height and finally 3,29 cm (± 0,38 cm) as for the mean width. Regarding the subgroup 3, the mean prostatic length was 3,09 cm (± 0,21), the mean height was 2,93 (± 0,21 cm) and the mean width was 3,63 cm (± 0,19), and these measurements showed to be shorter than the ones from subgroup 6, such as 3,47 cm (± 0,31) as for mean length, 3,35 cm (± 0,35 cm) as for the mean height and finally 4,03 cm (± 0,28 cm) as for the mean width. There was a high correlation between the prostatic dimensions and the body mass of theses dogs.