Relationship of mineral content of drinking water to liver lipid accumulation in laying hens

Qualidade da água de granjas de postura comercial da região Sul de Santa Catarina em relação ao Ofício Circular Conjunto DFIP/DSA nº 1/2008

O objetivo deste trabalho foi avaliar a qualidade da água de granjas de postura comercial da região Sul de Santa Catarina e contextualizá-la com o Ofício Circular Conjunto DFIP/DSA nº 1/2008. Em fevereiro de 2012 foram coletadas amostras de água de 31 granjas localizadas nos municípios de São Ludgero, Orleans, Grão Pará e Braço Norte. Os parâmetros químicos e microbiológicos avaliados foram os estabelecidos no anexo II do Oficio Circular Conjunto DFIP/DSA nº 1/2008. Sendo assim foram analisados cloreto, dureza, nitrato, sulfato, pH e sólidos dissolvidos totais (SDT) e Escherichia colino que se refere à análise bacteriológica. Quantificou-se a adequação das amostras em relação ao Ofício Circular Conjunto DFIP/DSA nº 1/2008 e avaliou-se a qualidade da água de acordo com o tipo de fonte e número de aves em produção por meio da análise de variância. Os resultados indicaram que as águas apresentaram adequação para SDT, cloreto e sulfato. Foi encontrada inadequação nos parâmetros: pH (em 26% das amostras), dureza (6,5%), nitrato (54,8%) e presença de Escherichia coli(46,2%). As análises de acordo com o número de aves e tipo de fonte não apresentaram diferença estatística significativa (p > 0,05). Observaram-se que 93,5% das amostras não se enquadraram em pelo menos um parâmetro. Concluíram-se que as águas das granjas da Região Sul de SC não estão totalmente de acordo com o Ofício Circular Conjunto DFIP/DSA nº 1/2008, apresentando problemas no que se refere ao pH, dureza, nitrato e E. coli; a qualidade da água independe do número de aves em produção e do tipo de fonte que abastece a granja.

Drinking water contaminants (arsenic, cadmium, lead, benzene, and trichloroethylene). 2. Effects on reproductive performance, egg quality, and embryo toxicity in broiler breeders

Broiler breeder hens were used to determine the effect of drinking water containing a low concentration of a chemical mixture (arsenic, 0.8 ppm; benzene, 1.3 ppm; cadmium, 5.1 ppm; lead, 6.7 ppm; and trichloroethylene, 0.65 ppm) and a high (10 times greater than the low concentration of the chemical mixture) levels of the chemical mixture. These chemicals are present in ground water near hazardous waste sites. Water consumption significantly decreased in chickens provided the high concentration of the chemical mixture, whereas feed consumption was not affected in any treatment. There was a linear relationship between increasing concentration of the chemical mixture in drinking water and decreasing body weight of hens. The low concentration of the chemical mixture significantly decreased egg production and egg weight, and increased percentage embryonic mortality. These results suggest that reproductive function in hens is sensitive to adverse effects of contaminated drinking water.

Calcium supplementation of hen drinking water

Two experiments with White Leghorn hens (42 and 56 wk old, respectively) examined the effects of calcium supplementation through drinking water in the presence of adequate and inadequate dietary calcium. Each experiment was of 28 d duration with six replicate pens of five individually caged hens in each treatment. Treatments were a combination of either 2.25 or 3.5% dietary calcium coupled with tap water or water supplemented with .2% calcium from calcium lactate. In both studies, specific gravity of eggs was significantly improved when low dietary calcium was supplemented with .2% calcium in the drinking water. Egg production and egg weight were not influenced by waterborne calcium. Daily water intake was reduced by calcium lactate in all cases. Feed consumption was also depressed by waterborne calcium in both studies when 3.5% dietary calcium was given, and in Experiment 1 when 2.25% was fed. Waterborne calcium as calcium lactate was found to be effectively utilized for eggshell quality improvement when dietary sources were inadequate.

Influence of diet composition on hepatic lipid accumulation and hemorrhages in caged layers

Four experiments were conducted with commercial strains of White Leghorns. Experimental corn-soy diets with (CSW) and without (CS) minor feed ingredients significantly elevated liver and plasma lipids when compared to a standard layer diet (UGA) used at the University of Georgia. The response was not due to difference in vitamin and mineral premix or level of energy and protein in the diets. Inclusion of 5% alfalfa in a low protein (13.5%) diet with energy and amino acid profile similar to diet CS significantly reduced liver lipid. Comparison of diet CS to isocaloric and isonitrogenous diets with 20% brewers dried grains, soybean mill feed, or wheat bran showed that layers fed diets with these supplements had significantly lower liver and plasma lipids. In all experiments a higher incidence of liver hemorrhage was associated with feeding the experimental diets CS and CSW. There were no significant differences in egg production, egg weight, or body weight change due to dietary treatment in the experiments. Results of the experiments show that hens with equivalent ME intake and egg output exhibit differences in liver and plasma lipids due to diet composition. The data suggest that mill feeds and fermentation by-products contain an essential factor for control of lipid metabolism in caged layers.