Estimation of genetic parameters for body areas in Nile tilapia measured by digital image analysis.

Digital image analysis is a practical, non-invasive, and relatively low-cost tool that may assist in the evaluation of body traits in Nile tilapia, being particularly useful for assessing difficult-to-measure variables, such as body areas. In this study, we aimed to estimate variance components and genetic parameters for body areas of Nile tilapia obtained by digital images. The data set comprised body weight (BW) records of 1,917 pond-reared fish at 366 days of age. Of this total, 656 animals were photographed and subjected to image analysis of trunk area (TA), head area (HA), caudal fin area (CFA) and fillet area (FA). Heritabilities and genetic correlations were estimated through multiple-trait models based on Bayesian inference. Heritability estimates for BW, TA, HA, CFA and FA were 0.25, 0.23, 0.26, 0.21 and 0.25, respectively. Genetic correlations between the traits were high and positive, ranging from 0.70 to 0.98. We highlight the genetic correlation between BW and TA (rG  = 0.98) and FA (rG  = 0.97). In view of the observed results, it can be concluded that trunk and fillet areas obtained by digital image analysis can lead to indirect genetic gains in weight and other body areas. In addition, the areas studied have potential as a selection criterion and may assist in studies on changes in the body shape in Nile tilapia.

[Replacing of residue from production of palm Palm Royal Australian (Archontophoenix alexan- drae) in silage of sugar cane in diets of sheep]. / Substituição do resíduo da produção de palmito da Palmeira Real Australiana (Archontophoenix alexandrae) na silagem de cana-de-açúcar em dietas de ovinos.

The aim of this study was to evaluate the chemical composition, voluntary intake and apparent digestibility of the diets containing residue from palm heart of Australian Royal Palm (Archontophoenix alexandrae) to replace sugar cane on sheep. Twelve sheep were used with average live weight of 23.3 ± 2.8 Kg and they placed in metabolism cages and distributed in six latin square 2 x 2 in a factorial design 3 x 2 (three types of residue--sheet, bark and composed--and two levels of residue's replacement, 5% and 15%). It was observed higher intake of dry matter (DM), organic matter (OM), nonfiber carbohydrates (NFC) by substitution of composed residue. The average values of apparent digestibility of DM, OM, crude protein (CP), neutral detergent fibre correct for ash and protein (NDFap) and total digestible nutrients (TDN) were higher for sheet residue. There was interaction between type of residue and level of residue's replacement on the urinary excretion of total nitrogen (NUE), apparent nitrogen balance (BNA) and microbial nitrogen compost (NMIC). Residues from palm heart of Australian Royal Palm can be used as roughage in the ruminants'diet, and of these residues, the sheet and composed residue showed better response in the evaluated characteristics.

Substituição do resíduo da produção de palmito da Palmeira Real Australiana (Archontophoenix alexandrae) na silagem de cana-de-açúcar em dietas de ovinos / Replacing of residue from production of palm Palm Royal Australian (Archontophoenix alexandrae) in silage of sugar cane in diets of sheep

Objetivou-se avaliar a composição química, consumo voluntário e digestibilidade aparente de dietas contendo resíduo oriundo da produção de palmito da palmeira Real Australiana (Archontophoenix alexandrae) em substituição à cana-de-açúcarem ovinos. Foram utilizados 12 ovinos com peso vivo médio de 23,3 ± 2,8 kg, mantidos em gaiolas metabólicas distribuídos em seis quadrados latinos 2x2 implementado em esquema fatorial 3 x 2 (três tipos de resíduo - folha, bainha e composta - e dois níveis de substituição do resíduo, 5% e 15%). Verificou-se maior consumo de matéria seca (MS), matéria orgânica (MO), carboidratos não fibrosos (CNF) na substituição pelo resíduo composta. Os valores médios de digestibilidade aparente da MS, MO, Proteína bruta (PB), fibra insolúvel em detergente neutro corrigido para cinzas e proteína(FDNcp) e nível dietético de NDT foram maiores para o resíduo folha. Constatou- se efeito de interação entre resíduo e o nível de substituição sobre as excreções urinárias de nitrogênio total (EUN), balanço nitrogenado aparente (BNA) e compostos nitrogenados microbianos (NMIC). Resíduos da produção de palmito oriundos da palmeira Real Australiana podem ser utilizados como alimentos volumosos na dieta de animais ruminantes, sendo destes, o resíduo folha e composta os que apresentaram melhores respostas nas características avaliadas.

The aim of this study was to evaluate the chemical composition, voluntary intake and apparent digestibility of the diets containing residue from palm heart of Australian Royal Palm (Archontophoenix alexandrae) to replace sugar cane on sheep. Twelve sheep were used with average live weight of 23,3 ± 2,8 Kg and they placed in metabolism cages and distributed in six latin square 2 x 2 in a factorial design 3 x 2 (three types of residue -sheet, bark and composed - and two levels of residue’s replacement, 5% and 15%). It was observed higher intake of dry matter (DM), organic matter (OM), nonfiber carbohydrates (NFC) by substitution of composed residue. The average values of apparent digestibility of DM, OM, crude protein (CP), neutral detergent fibre correct for ash and protein (NDFap) and total digestible nutrients (TDN) were higher for sheet residue. There was interaction between type of residue and level of residue’s replacement on the urinary excretion of total nitrogen (NUE), apparent nitrogen balance (BNA) and microbial nitrogen compost (NMIC). Residues from palm heart of Australian Royal Palm can be used as roughage in the ruminants’diet, and of these residues, the sheet and composed residue showed better response in the evaluated characteristics.