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Endemic to the south‐west Atlantic Ocean, the shortnose guitarfish (Zapteryx brevirostris) is a small species, classified as endangered by the IUCN. Although reproduction in captivity has been successful for some species, a range of factors can limit the success of captive breeding programmes for elasmobranchs. In Brazil, the Ubatuba Aquarium was the first public aquarium to reproduce small‐sized elasmobranchs. Since 2018, at least five parturition events have been recorded for Z. brevirostris at the institution. From a total of 13 live neonates that rearing was attempted, the mean ± standard error of weight, total length (TL) and disc width at birth were 17.47 ± 1.6 g, 13.25 ± 0.7 cm and 6.53 ± 0.2 cm, respectively. The mean weight as well as mean TL were higher for females at all births, with 26.15 g and 15.07 cm for females in comparison with 17.09 g and 13.94 cm for males. Considering the increasing risk of extinction that the species is facing, age and growth studies are fundamental for the success of conservation, improving the knowledge of Z. brevirostris life cycle so that a more efficient and sustainable management can be carried out. This study provides important data, as well as directions for captive breeding of the species.

The objective of the present study was to evaluate the incidence and prevalence of lesions in the face of piglets and the subsequent effects on their performance. The treatments used were the maintenance and wear of incisors and canines. Evaluations were performed on the second and fourth day after birth and three times a week until weaning. The lesions were classified as type A and B. Conventional methods were used to analyze the zootechnical parameters and body temperature was measured in the ventral and dorsal region of the piglets, twice a day. The chi-square test was used to evaluate the effect of treatment on the prevalence of piglets with Type A and Type B lesions. Mean values of body temperature and weight gain per treatment were compared by Fischer Means Test. In relation to weight gain, a variance analysis was performed considering the location of the effects and the treatment. The percentage total lesions found in piglets in both treatments was 39.2%. Type B lesions accounted for 20.5%. Significant differences were found for the periods evaluated. In this study, severe lesions were found in piglets with teeth, however, the use of wear tooth is unnecessary, as there are lesions that occur in this practice due to poor management of piglets and sows during lactation. Female weight gain after farrowing and lactation was not affected by maintenance of intact teeth or by weaning, as well as gain of piglets after birth and weaning. However, for piglets at weaning, there was a trend, since the weight found at site I was higher than site II and III. It is concluded from the results of this study that tooth wear should be performed only when necessary.inforMAtion Cronología del artículo.Recibido/

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