| Gizzerosine in fish meal feed brings about gizzard erosion and ulceration, inappetence, decrease of spawning rate, a serious disease called’Black Vomit’, death in chicks, ducks, fish and other breeding animals. Gizzerosine is generated during the heat treatment of brown fish meal. The level of gizzerosine which can cause pathological changes is about 1 mg/kg, whose physiological toxicity is 1000 times as histamine in fish meal. The main reason which caused animal pathogenic is promoting gastric acid secretion and resulting in mucosa lesions.The research established method for gizzerosine analysis by high performance liquid chromatography. Fish meal sample was extracted with 80% ethanol, then the solution was filtered by the organic filter membrane.The gizzerosine wes derivated by nitrogen coupling reaction, and separated at a flow rate of l.Oml/min in a ODS reversed-phase description gemini 5 u C18 110A(250×4.6 mm) at 40℃, by using acetonitrile and sodium acetate buffer as a gradient elution. The results showed the method had good linear relation over the concentration range from 0.001 mg/ml to 0.5 mg/ml for gizzerosine with correlation coefficient(R2) 0.9942 and equation y = 8061.6 x-120716 and the RSD was 0.75%. The average recovery was 100.17%. The method is simple, rapid, sensitive and convenient, and could be applied in analysis and determination of gizzerosine in fish meal.The research studied the formation mechanism of gizzerosine in fish meal and found that histamine was the roof cause of gizzerosine through analysis in different aspects of physics,chemistry and physiology.Fish didn’t produce histamine under the nature condition.The existence of histamine due to the large population of bacteria that leads to fish rot.The bacteria were separated and cultured using different kinds of mediums and paper electrophpresis and isolated one histamine bacterium. The research also studied the relationship between lysine and gizzerosine formation briefly.Mackerel fish meal were obtained under different histamine content, temperature, pH, drying time and other conditions in this experiment, and the gizzerosine content of each meal was measured by high performance liquid chromatography method. The results showed that gizzerosine increased gradually with the increase of histamine, which came to the maximum of 301.63mg/kg when histamine content was 6000mg/kg; gizzerosine increased at first and then reduced with the increase of drying time extending, it was detected at the least level of 198.51mg/kg when the heating time was lh and the most level of 269.52mg/kg when the heating time was 3h ; gizzerosine increased at first and then reduced with the increase of drying temperature and pH, it was detected at the most level of 225.02mg/kg when the heating temperature was 130℃ and 63.96mg/kg at pH 6.6.The experiment was carried out in 6 four-day-old broilers in Guangdong which were divided into 2 groups and fed the basal diet for 7days.The experimental group were injected 10mg/kg gizzerosine standard solution every day, and the control group was not disposed.Broilers Weight and morphologic were observed every day. After anatomy,the samples of stomach, liver, were observed and detected for gizzerosine,the volume and pH of succus gastricus,the activity of stomach protease,the gastric musoca section.The results showed that compared to the control group,the growth rate of experimental group was slower and one chicken was dead.The glandular stomachs were swelling with red spots.The color of livers were lighter and more broken.The volume of succus gastricus increased,while the pH decreased. All chickens in the experimental group appeared gizzard erosion. |
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