Differences In Testicular Histomorphology,Semen Quality And Genetic Contribution Rates According To Sperm Mobility In Zie Geese

Sperm mobility is an important method to measure sperm motility in poultry.In this study,goose sperm mobility was determined.The differences in sperm mitochondrial activity,sperm kinematic parameters and semen quality traits of ganders with different sperm mobility were compared.Changes in testicular histomorphology and reproductive hormone levels with different sperm mobility ganders were analyzed.Using genetic markers,the individual genetic contribution rates of males with different sperm mobility under natural mating conditions were determined,and the differences in reproductive efficiency of ganders were analyzed.40 24-month-old ganders with the same genetic background,same age and similar body condition and well-developed were selected and raised separately.The semen was collected individually in 5 installments(once per week).Sperm mobility was determined for the individual ganders.According to the principle of at least one standard deviation(?x±SD),40 ganders were divided into high and low sperm mobility groups,6 in each group.Sperm viability sperm concentration sperm abnormality was measured.The sperm motility and sperm kinematic parameters were measured with the Computer-Assisted Sperm Analysis System(CASA).Sperm mitochondrial activity was observed by fluorescence microscope.Elisa was used to measure the concentration of testosterone(T),follicle stimulating hormone(FSH),and luteinizing hormone(LH).To determine the effect of males with different sperm mobility on the reproductive efficiency,each group of ganders was reared with 30 female geese.Eggs were collected and hatched once a week for total three times consecutively,the reproduction efficiency of each gander were measured.Blood from parent and offspring goslings were collected,and then DNA was extracted.Based on microsatellite DNA markers,the number of goslings and genetic contribution for each gander were calculated by a paternity test,and reproductive efficiency of different sperm mobility groups was compared.Testicular from ganders were collected for each groups.The testis tissue of each group of males was collected and weighed,and the diameter of seminiferous tubules and the height of seminiferous epithelium were observed by paraffin section technique.The differences among the indicators were analyzed according to the Mann-Whitney test.The results showed(1)that high sperm mobility group was 0.41 Abs,low sperm mobility group sperm mobility was 0.10 Abs,there was highly significant difference between the two groups(P < 0.01).The sperm motility(P < 0.01),sperm viability and sperm mitochondrial activity(P < 0.05)of geese in the high sperm mobility group were higher than those in the low sperm mobility group.Average path velocity(VAP),linear velocity(VSL),curvilinear velocity(VCL),forwardness(STR),linearity(LIN),whiplash frequency(BCF)among sperm motility parameters of geese in high and low sperm mobility groups.The difference was extremely significant(P < 0.01),and the side swing amplitude(ALH)was significantly different(P <0.05).(2)In the high sperm mobility group,the combined testis weight,diameter of seminiferous tubules,height of seminiferous epithelium and sperm maturity were higher than those in the low sperm mobility group(P < 0.05).T was 312.41 ng/m L and 253.02 ng/m L,and FSH was 1.65 m IU/m L and 1.42 m IU/m L,respectively.There was a significant difference between the two groups(P < 0.05).(3)In the case of natural mating,the genetic contribution rate(GCR)of male geese in high and low mobility groups were 26.47 %,25.29 %,17.06 %,15.29 %,8.24 %,7.65 % and 30.00 %,29.09 %,14.55 %,12.73 %,7.27 %,6.36 %.The GCR of male geese within each group varied widely.The fertilization rate of the high mobility group was 93.69 % and the hatching rate was 88.06 %.The fertilization rate of the low sperm mobility group was 84.06 %,and the hatching rate was 78.01 %.The fertilization rate and hatching rate of the high and low sperm mobility groups were significantly different(P <0.05).There were significant differences in sperm kinematic parameters,semen quality traits and sperm mitochondrial activity in geese with different sperm mobility.At the same time,the sperm mobility was also affected by testis tissue structure and T and FSH.Sperm mobility can be used to evaluate the reproductive efficiency of naturally mating geese.In geese breeding,high fecundity males can be selected by measuring sperm mobility.