Effects Of Dietary Iodine Levels On Growth Performance,Muscle And Fcur Quality,Lipid And Nitrogen Metabolism Of Growing Rex Rabbits

This subject adopts the single factor experiment design method,studies the growth of the3-5 months rabbit fodder iodine can appropriate to add content and iodine on the production performance of otter,muscles,and fur quality,fat,and the influence of nitrogen metabolism.Physical conditions of this test is only 200 similar health rabbit,number of male female,were randomly divided into 5 groups(each group of 40 repeat,repeat each 1 only),feeding is added in the basic diet,respectively 0,0.2,0.4,0.8,1.6 mg/kg iodine diet(potassium iodide)test.The pre-test period is 7 d,and the trial period is 60 d.During the experiment,single cage feeding,routine feeding management and immunization procedures were used,feeding twice daily at 08:00 PM,ensuring free food intake and free drinking water,natural ventilation and lighting.The test results are as follows:(1)the diet iodine level of meat performance: the influence of the initial weight(IBW)there was no significant difference(P > 0.05),the different iodine level of 3~5 months(FBW)have a significant impact on growth of otter terminal weight(P < 0.05),and when the iodine content in foods was 0.8 mg/kg,the rabbit terminal can reach maximum weight 3.33 kg.At the same time,when 0.8 mg/kg of iodine was added to the basic diet,the average daily intake(ADFI)was significantly affected(P=0.0001).There was no significant effect on the average daily gain weight(ADG)and the weight ratio(F/G)in the daily diet with different amounts of iodine(P > 0.05).Fodder iodine added level of rabbit whole eviscerated ratio,back waist ratio and muscle quality indicators(pH,water loss rate,shear force,and nude(brightness,yellow degree value))had no significant influence(P > 0.05),on the hind leg muscle rate and muscle red has significant effect(P < 0.05),has a significant effect on the front leg muscle rate(P < 0.01).(2)the diet iodine level for fur quality: the influence of the different iodine level of 3~5months beaver rabbit’s fur is the area of significant effects(P < 0.01),weight of fur,skinthickness,white degree and tear strength has significant effect(P < 0.05),the length of the thickness,fur coat,fur is density,tensile strength,elongation and tearing load the thickness of the breakpoint is no significant influence(P > 0.05).(3)the diet iodine levels of nitrogen utilization: the influence of the different iodine level of 3~5 months beaver rabbit feed into the nitrogen(IN)and nitrogen deposition(RN)has significant effect(P < 0.05),the fecal nitrogen(FN),urine nitrogen(UN),digestible nitrogen(DN),apparent digestibility of nitrogen(NAD),nitrogen utilization efficiency(NUR)and biological titer(NBV argues)effect was not significant(P > 0.05).(4)diet iodine level of rabbit vital organs: the influence of the different iodine level of3~5 months rabbit thymus,spleen,liver,kidney and thyroid weight and each organ index effect was not significant(P > 0.05).(5)the effect of daily food iodine level on the fat deposition of rabbits: the influence of different iodine levels on the growth of the gastric peripheral fat,the shoulder fat and the renal weekly fat of the growth otter rabbit was not significant(P>0.05).(6)the diet iodine level of rabbit serum biochemical indexes: the influence of the different foods iodine level of influence on the growth of otter Thyroid stimulating hormone(TSH),Four iodosine adenosine(T4)and Free four iodide adenosine(FT4)significantly(P <0.01),has a significant effect on Three iodosine adenosine(T3)(P < 0.05),the influence to Free three iodide adenosine(FT3)was not significant(P > 0.05).(7)the diet iodine level affect the gene expression of rabbit hair follicle development:fodder different iodine levels on the growth of otter Noggin mRNA expression quantity has significant effect(P < 0.05),to the Ver,HGF,ALP,BMP2 and BMP4 the influence of the amount of mRNA expression were not significant(P > 0.05).(8)the influence of dietary iodine level on the growth axis gene expression of rabbits: the influence of different iodine levels on the growth of rabbit GH,IGF-1 and IGFBP1 was not significant(P>0.05).(9)the effect of dietary iodine level on protein expression in the growth and development of rabbits was not significant(p > 0.05).The effect of different iodine levels on the expressionof p-ampk and p-wnt protein in the growth otter rabbit was not significant.In this test,the appropriate iodine addition level of 3~5 months of growth was 0.8 mg/kg(the measured value of iodine in basal diet was 0.92 mg/kg).