Research Of The Optimal Manganese Level In Basal Diet Of Femal Minks’ Breeding Period

In this study, we added different levels of organic chelated manganese to the basal dietof femal minks, and combined with digestion metabolism, serum biochemical, reproductiveperformance and part of the trace element metabolism indexes, to determine the optimalmanganese level in basal diet of femal minks’breeding period. We laid the foundation forperfecting mink diet nutrition standards and providing a scientific theoretical basis to feedminks.One hundred and fifty healthy female minks with the body weight of1.01±0.11kgwere selected and assigned into five groups by randomized blocks; there were thirty minksin each group. Supplemental levels of manganese in basal diets were0(group Ⅰ),15(group Ⅱ),50(group Ⅲ),100(group Ⅳ) and500mg/kg (group Ⅴ), respectively.Manganese was added as organic chelating form. Basal diet group (Ⅰ) manganese contentswere26.46mg/kg in the pre-mating period and24.54mg/kg in the pregnancy and lactationperiod. The paper was writed in accordance with the breeding stages and the meta-analysisresults were as follows:1. Organic chelated manganese contents in the diet could affect nutrient digestibility.The dry matter, crude protein and crude fat apparent digestibility, and the rate of proteindeposition were the highest when we added the level of manganese as100mg/kg into dietduring the pre-mating period, compared with the control group respectively increase by5.89%,1.97%,0.93%and20.84%. The dry matter and crude protein apparent digestibilitywere the highest when we added the level of manganese as50mg/kg into diet during thepregnancy period, compared with the control group respectively increase by0.34%,2.41%.The fat apparent digestibility and the net protein utilization were the highest when we addedthe level of manganese as100mg/kg into diet during the pregnancy period, compared withthe control group respectively increase by1.13%,33.01%. Manganese was appropriate toadd the range of50-100mg/kg into diet during the pregnancy period.2. Organic chelated manganese contents in the diet had significant difference to parts ofthe mink serum biochemical indexes. Different manganese levels in diet had significantlyinfluence on the contents of serum LDH, GPT/ALT and GOT/AST during the pre-matingperiod (P<0.01). Different manganese levels in diet had significantly influence on thecontents of serum GPT/ALT, GOT/AST, ALP and Mn-SOD during the pregnancy period (P<0.01or P<0.05). Different manganese levels in diet had significantly influence on thecontents of serum LDH, GPT/ALT, GOT/AST, ALP and TP during the late lactation(P<0.01or P<0.05).3. Organic chelated manganese contents in the diet could affect trace elements. Withthe rise of the level of dietary manganese, manganese contents was increased in serum, hair,fecal, urine and initial young minks, manganese retention rate and apparent digestibilitydecreased. Diet with added Mn can promote Fe excretion. There were no significantdifferences on Cu, Zn. Cu retention was the highest in group with50mg/kg manganese onbasal diet. Fe, Zn retention in initial minks was affected significantly by added manganesecontent in diet, and had a highest retention in group50mg/kg.4. Diet supplemented with organic chelated manganese (except group Ⅱ) couldimprove fertility rate, weaning survival rate, litter size and number weaned, and the highestwas the group with500mg/kg manganese on basal diet, compared with the control grouprespectively increase by7.42%,11.99%,0.41and0.68, but which could decrease growthperformance of kit minks. The group which added100mg/kg manganese to basal dietcompared with the control group respectively increase by1.27%,5.22%,0.38and0.57.Comprehensive economic benefits and growth performance, the optimal additionmanganese level in basal diet was100mg/kg.Comprehensive all the indexes, manganese in the diet during breeding period addedrange was50to100mg/kg and the total amount of manganese was75to125mg/kg, whichcould reach a best production performance.