Resumo
Every year, Brazil receives large flocks of nearly 40 migratory shorebirds species. The accumulation of body fat and nutrients during the summer is necessary for the long return flights of these birds and is fundamental for feather moulting and the change of their plumage. We present here an examination of the relationship between body mass and plumage change in Arenaria interpres (Linnaeus, 1758), one of those birds, over time during its wintering period on the Brazilian coast. We analyzed information collected at five traditional stopover sites along the Brazilian coast, between 1997 and 2007. During the month of September, individuals with intermediate or breeding plumage had smaller body masses as compared to other months. From October to December, adult individuals were only observed with eclipse plumage and had average body masses of approximately 100 g. In March, individuals with intermediate, eclipse and breeding plumages were recorded, but their average body mass remained at approximately 100 g. In April and May the numbers of individuals with breeding or intermediate plumage increased, and they showed significant increases in body mass at a rate of approximately 1.5 and 2.3 g per day, in the north-northeastern and south coast, respectively, leading to an average mass of 124 and 143g in these months. That is suggested to be the departure mass of A. interpres in the Brazilian north-northeastern and south coast, respectively, when starting the migration to the breeding sites.
Resumo
Every year, Brazil receives large flocks of nearly 40 migratory shorebirds species. The accumulation of body fat and nutrients during the summer is necessary for the long return flights of these birds and is fundamental for feather moulting and the change of their plumage. We present here an examination of the relationship between body mass and plumage change in Arenaria interpres (Linnaeus, 1758), one of those birds, over time during its wintering period on the Brazilian coast. We analyzed information collected at five traditional stopover sites along the Brazilian coast, between 1997 and 2007. During the month of September, individuals with intermediate or breeding plumage had smaller body masses as compared to other months. From October to December, adult individuals were only observed with eclipse plumage and had average body masses of approximately 100 g. In March, individuals with intermediate, eclipse and breeding plumages were recorded, but their average body mass remained at approximately 100 g. In April and May the numbers of individuals with breeding or intermediate plumage increased, and they showed significant increases in body mass at a rate of approximately 1.5 and 2.3 g per day, in the north-northeastern and south coast, respectively, leading to an average mass of 124 and 143g in these months. That is suggested to be the departure mass of A. interpres in the Brazilian north-northeastern and south coast, respectively, when starting the migration to the breeding sites.
Resumo
Every year, Brazil receives large flocks of nearly 40 migratory shorebirds species. The accumulation of body fat and nutrients during the summer is necessary for the long return flights of these birds and is fundamental for feather moulting and the change of their plumage. We present here an examination of the relationship between body mass and plumage change in Arenaria interpres (Linnaeus, 1758), one of those birds, over time during its wintering period on the Brazilian coast. We analyzed information collected at five traditional stopover sites along the Brazilian coast, between 1997 and 2007. During the month of September, individuals with intermediate or breeding plumage had smaller body masses as compared to other months. From October to December, adult individuals were only observed with eclipse plumage and had average body masses of approximately 100 g. In March, individuals with intermediate, eclipse and breeding plumages were recorded, but their average body mass remained at approximately 100 g. In April and May the numbers of individuals with breeding or intermediate plumage increased, and they showed significant increases in body mass at a rate of approximately 1.5 and 2.3 g per day, in the north-northeastern and south coast, respectively, leading to an average mass of 124 and 143g in these months. That is suggested to be the departure mass of A. interpres in the Brazilian north-northeastern and south coast, respectively, when starting the migration to the breeding sites.
Resumo
One experiment was conducted to study performance of laying hens of four strains after forced molt: Lohmann White, Babcok, Embrapa-011 (light weight) and Lohmann Brown (semi-heavy weight). Different levels of calcium were applied during the production period (2, 3, 4, 5 and 6%), the experimental design was a random block design with whole 400 birds. Hens were 74 week old at the beginning of the molt phase. The birds fed 2% of calcium showed lower feed consumption and lower egg production. The highest levels of calcium increased the egg shell quality. The color of egg yolk was lower for levels 2 and 6% of calcium. Egg weight, Haugh unit and egg yolk color were related to strain, and the Embrapa-011 showed the lower performance among strains.
O experimento foi conduzido com o objetivo de comparar o desempenho produtivo de poedeiras, de 4 linhagens (Lohmann White, Babcock, Embrapa-011 e Lohmann Brown), pós-muda forçada recebendo diferentes níveis de cálcio nas rações (2, 3, 4, 5 e 6%). O delineamento experimental foi em blocos ao acaso, sendo utilizadas 100 aves por linhagem, com 74 semanas de idade. As aves que receberam 2% de cálcio apresentaram menor consumo de ração e produção de ovos; os maiores níveis de cálcio aumentaram a qualidade da casca dos ovos. A cor da gema foi menor para os níveis 2 e 6%. As variáveis peso dos ovos, Unidades Haugh e cor da gema foram relacionadas com a linhagem, e a Embrapa-011 apresentou o pior desempenho entre as linhagens.