The Effect Of Early Castration On The Growth And Development Of Pigs And The Physiological Structure Of Various Functional Tissues And Organs

Castration is an important means to promote the growth and meat quality of livestock and poultry.It can promote growth,reduce fighting and improve pork quality in male piglets.Therefore,with the improvement of the demand for pork quality in the market,castration technology has been widely and deeply promoted and applied in livestock such as pigs,cattle and sheep.Castration can be divided into chemical castration,immune castration and physical castration,With the improvement of living standards,animal welfare has also received extensive attention.From the perspective of humanitarianism,animal welfare has been valued,and the improvement of animal well-being has become an important indicator for assessing castration and guaranteeing animal welfare.Studies have shown that male pigs emasculation can promote growth,reduce fighting and improve pork quality,while the effects on the organs of piglets after emasculation have not been fully and carefully reported.In this paper,the model of castrated pig was constructed,and the effect of castrated pig growth and development as well as the physiological structure of various functional tissues and organs was evaluated by measuring the body size and slaughter indexes.The main results are as follows:1.Serum testosterone concentration: > single castration group > control group;Testicular weight: testicular weight of control group < single castration group(p < 0.01);Accessory gland weight: the seminal vesicle weight > in the single castration group,the seminal vesicle weight > in the double castration group,the difference between the control group and the double castration group was very significant(p < 0.01);There was a significant difference between the single castration group and the bipotential group(p < 0.01).In the control group,urethral bulb gland weight of > single castration group and > double castration group was significantly different(p < 0.01)from the control group,and the single castration group and the double castration group were significantly different(p < 0.01).The testicular weight of the control group was >,but the difference was not significant(p>0.05).2.Sex hormone secretion: estradiol in the control group < estradiol in the single castration group < estradiol in the double castration group,the difference between the control group and the single castration group is extremely significant(p < 0.01),the difference between the control group and the double castration group is extremely significant(p < 0.01),and the difference between the single castration group and the double castration group is extremely significant(p < 0.01).In the control group,progesterone > single castration group and progesterone > double castration group were significantly different(p < 0.01),in the control group and the single castration group(p < 0.01),in the control group and the double castration group(p < 0.01),and in the single castration group and the double castration group(p < 0.01).No changes were observed in pituitary prolactin,luteinizing hormone and follicle stimulating hormone(p > 0.05).3.Body length of control group < body length of single castration group < body length of double castration group(p > 0.05).4.Muscle fat: the longissimus dorsi PH1> in the double emasculation group and the longissimus dorsi PH1> in the single emasculation group;The longissimus dorsi PH2> in the single emasculation group and the longissimus dorsi PH2> in the double emasculation group;Control group lumbago major muscle PH1= double emasculation group lumbago major muscle PH1> single emasculation group lumbago major muscle PH1;Control group lumbar major muscle PH2> single emasculation group lumbar major muscle PH2> double emasculation group lumbar major muscle PH2;The effect of emasculation on the PH of the longissimus dorsi and the lumbar major muscle was not significant(p > 0.05).Muscle fat histology: castration reduces muscle fiber diameter and increases fat deposition.5.Carcass index: the back mark thickness of the control group < the back mark thickness of the single castration group < the back mark thickness of the double castration group,the difference between the control group and the double castration group was extremely significant(p < 0.01),the difference between the control group and the single castration group was not significant(p > 0.05),and the difference between the single castration group and the double castration group was not significant(p > 0.05).No significant differences were found in eye muscle area between the three groups(p > 0.05).At the same time,castration increased the weight,chest circumference and waist circumference of the pig.But the effect of emasculation on neck circumference was not significant.6.Lung weight of the treatment group was significantly higher than that of the control group(p < 0.01).The kidney weight of the control group was significantly higher than that of the control group(p < 0.01),while the kidney weight of the control group was significantly higher than that of the control group(p < 0.01).Weight of internal organs: the heart weight of the single castration group was > Control group cardiac weight>the heart weight of the double castration group,and there was no significant difference in the heart weight between the three groups(p > 0.05).Liver weight of the control group was > single castration group,liver weight of the double castration group was > double castration group,liver weight of control group > single castration group of > double castration group,no significant difference among the three groups(p > 0.05);the spleen weight of single castration group > the control group >double castration group,but no significant difference among the three groups(p > 0.05).In general,through the comprehensive analysis of every organ of the castration pig model,the effect of castration on the growth and development of pigs and the physiological structure of various functional tissues and organs was evaluated from various indicators,which has a certain guiding effect on improving the quality of pork.