| Sodium sulfate(Na2SO4), inorganic compounds, widely used for paper, glass, chemicals, fuel and other industries, and seldom used in livestock and poultry production. Recent studies showed that, adding proper sodium sulfate in feed can promote growth and development of animals with increased milk yield, wool production and improve the feed efficiency, and also improve the quality of animal products and raise the economic efficiency. The effects of sodium sulfate, associated with its dose. Hypertonic solution can be formed in intestinal tract by higher does sulfate. It will promote gastrointestinal motility and increased the secretion of intestinal cells moisture, then make the animals diarrhea. Therefore, a small dose of sodium sulfate add in dietary conducive stomach, and at higher doses induced cause diarrhea and other symptoms.This topic through two breeding experiment, studied the smallest does of sodium sulfate added in diet that is effective, and the biggest does of sodium sulfate added in diet that is safe. 1) This study explored the effect of dietary supplementation of sodium sulfate at various levels(low dose) on performance, egg quality of laying hens, explore the effective dosage of sodium sulfate in laying hens fodder add, provide the reference and theoretical basis for the application of sodium sulfate in the production practice of scientific guidance. 2) This study explored the effect of dietary supplementation of sodium sulfate at various levels(high dose) on performance, egg quality, viscera histopathological observation of laying hens, explore the safety limit of sodium sulfate in laying hens fodder add, provide the reference and theoretical basis for the application of sodium sulfate in the production practice of scientific guidance. Trial 1: Study on the effectiveness of sodium sulfate in laying hensThis study was conducted to investigate the effective dosage of sodium sulfate in laying hens fodder add. The completed random of single factor was introduced to this experiment. 19 week age, 360 Jing Brown laying hens according to body equal, good physical condition, consistent rate of laying completely randomized design, were randomly allotted in five treatments, and each treatment consisted of 6 replicates of 12 hens. All birds were acclimated to the basal diet for 1 week. Five groups of laying hens fed a corn and soybean meal based diet were supplemented with 0, 0.3, 0.6, 0.9,1.2% of sodium sulfate for 8week with free access to feed and water, and laying performance, eggshell qualities and blood ion(potassium, sodium, chloride) were measured. The date showed that:1) Compare with the control, diets supplemented with 0.3, 0.6, 0.9, and 1.2% sodium sulfate had no significant effects on average egg weight, average feed intake, laying rate(P>0.05). Early(1~4 weeks) F/E significant difference among treatment groups(P<0.05), 0.6% group was significantly lower than the control. Added sodium sulfate in diet have significant effects on layer body weight(P<0.01), and layer body weight increase linearly as the diet supplement sodium sulfate increases. A trend of decrease mortality have been showed as sodium sulfate dosage increased(P<0.1).2) Feeding diets supplemented with sodium sulfate did not influence egg shape index, shell thickness(P>0.05). Treats the 2nd week, the 4th week, the 8th week, diets supplemented with sodium sulfate had significant effects on eggshell strength(P<0.05). Compare with the control, 0.6% group was significantly improve the eggshell strength(P<0.05). Dietary sodium sulfate in each stage had no significant effects on yolk colour(P>0.05). On week 4, dietary sodium sulfate significantly improve the haugh units(P<0.05), and had a trend of increase albumen height(0.1<P<0.05). The others phases, diets supplemented with sodium sulfate had no significant effects on haugh units and albumen height(P>0.05).3) Dietary sodium sulfate had no significant effects on sodium concentration in blood(P>0.05). On week 8, dietary sodium sulfate can improve the laying hens blood chlorine ion concentration(P<0.05), had a trend of decrease blood potassium ion concentration(0.1<P<0.05). Above all, diet supplement with sodium sulfate can improve production performance, eggshell quality of laying hens, with 0.6% level for the best. Suggest the best level of diet supplement with sodium sulfate is 0.6%. Trial 2: Study on the tolerance of sodium sulfate in laying hensThis study explored the effect of dietary supplementation of sodium sulfate at various levels(high dose) on performance, egg quality, viscera histopathological observation of laying hens, than explore the safety dose of sodium sulfate in laying hens fodder add. The completed random of single factor was introduced to this experiment. 21 week age, 360 Jing Brown laying hens according to body equal, good physical condition, consistent rate of laying completely randomized design, were randomly allotted in five treatments, and each treatment consisted of 6 replicates of 12 hens. All birds were acclimated to the basal diet for 1 week. Five groups of laying hens fed a corn and soybean meal based diet were supplemented with 0, 0.6, 1.2, 1.8, 3.0% of sodium sulfate for 8 week with free access to feed and water, and laying performance, eggshell qualities, blood gas indices, hematological indices, serum biochemical parameters, organ coefficient, pathological sections of organ were measured. The date showed that:1) Compare with the control, diets supplemented with 0.3, 0.6, 0.9, and 1.2% sodium sulfate had no significant effects on average egg weight, average feed intake, feed to egg ratio(P>0.05). In late phase(5~8 weeks), level of 1.8% and 3.0% sodium sulfate reduced the laying rate, significantly lower than 0.6% group(P<0.05).2) Feeding diets supplemented with sodium sulfate did not influence egg shape index, yolk colour, albumen height(P>0.05). On week 4, compare with the control, diets supplemented with 3.0% sodium sulfate had significant improve haugh units(P<0.05), 0.6% group had significant improve eggshell strength(P<0.01). On week 8, compare with the control, 1.8% and 3.0% groups had most significant decrease eggshell strength(P<0.01).3) Feeding diets supplemented with sodium sulfate did not influence blood p H and O2 partial pressure, CO2 partial pressure, Sa O2 and HCO3- concentration(P>0.05). On 8 week, blood potassium concentration of treatment groups had significant lower than the control(P<0.05), and blood potassium concentration in laying hens was in significant binomial relationship with the dose of sodium sulfate add in diet(y=0.051x2-0.428x+4.584,R2=0.914). Compare with the control, dietary sodium sulfate has a trend to improve blood chlorine ion content(P<0.01). 4) Compare with the control, diets supplemented with 0.3, 0.6, 0.9, and 1.2% sodium sulfate had no significant effects on red blood cells, weight, white blood cell specific volume(P>0.05). Compare with control croup, diets supplemented with 0.3, 0.6, 0.9, and 1.2% sodium sulfate had significant decrease blood platelet(P<0.05). 3.0% sodium sulfate had significantly increased red blood cells. 1.8% and 3.0% sodium sulfate had a trend to increase hemoglobin(P<0.1).5) Compare with the control, diets supplemented with 0.3, 0.6, 0.9, and 1.2% sodium sulfate had no significant effects on plasma uric acid, creatinine, phosphokinase, cereal third transaminase, aspertate aminotransferase and total bilirubin(P>0.05). 3.0% sodium sulfate had significantly reduce plasma total protein, albumin and glucose levels(P<0.05). Compare with the control, 1.8% and 3.0% sodium sulfate extremely significantly elevated plasma uric acid content(P<0.01). Plasma glucose levels had a trend to reduce as increase of sodium sulfate dosage(P<0.1), Compare with the control, 3.0% sodium sulfate extremely significantly decreased plasma glucose levels(P<0.01). 6) Feeding diets supplemented with sodium sulfate did not influence heart, spleen and lung coefficient(P>0.05), significantly influence liver, kidney and pancreas coefficient(P<0.05). Compare with the control, 3.0% sodium sulfate had significantly increase liver and kidney coefficient(P<0.05), 1.8% and 3.0% significantly decrease pancreas(P<0.05).7) The morphology of liver organs showed that all treatments of liver biopsy tissue structure is clear, fatty scattering in hepatic cell, a small quantity of inflammatory cells scattering in sinusoidal endothelial cells. The morphology of different organs of 1.8%, 3.0% sodium sulfate showed that glomerular atrophy, lots of inflammatory cells immersed in villous stroma. Above all, worst performance of treatment with 1.8% and 3.0% sodium sulfate,and significantly decreased egg quality in later stage, the kidneys and intestinal tissue pathological changes occur. In conclusion, the tolerance dose of the Na2SO4 in diet was 1.2%. |
