China Animal Husbandry and Veterinary Medicine ›› 2024, Vol. 51 ›› Issue (6): 2644-2652.doi: 10.16431/j.cnki.1671-7236.2024.06.038

• Preventive Veterinary Medicine • Previous Articles    

Infection Status of Giardia duodenalis in Cattle in Yunnan Province Based on gdh Gene

WANG Wenya1, XIE Xinyan1, YAN Dalong1, WEI Penghao1, YANG Jianling1, BI Run2, LI Qing3, MA Jun1, ZOU Fengcai1   

  1. 1. College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China;
    2. Menghai County Animal Husbandry and Veterinary Workstation, Xishuangbanna 666200, China;
    3. Luoping Agriculture and Rural Comprehensive Service Center of Jiulong Street, Qujing 655800, China
  • Received:2023-11-21 Published:2024-06-01

Abstract: 【Objective】 This study was aimed to investigate the infection and genotype distribution of Giardia duodenalis (G.duodenalis) in cattle in Yunnan province,and evaluate the transmission risk of giardiasis.【Method】 Nested PCR was used to detect fresh fecal samples of 258 cattle collected from three regions in Yunnan province based on the glutamate dehydrogenase (gdh) gene of G.duodenalis.The positive rates of G.duodenalis in different regions,ages,and breeds of cattle were calculated.Positive samples were sequenced,and the sequencing results were submitted to NCBI for genotype identification.MrBayes 3.1 was used in Bayesian inference analysis and construct a phylogenetic tree,choosing GTR (general time reversible) model.【Result】 23 of 258 faecal samples were positive for G.duodenalis,and the total positive rate was 8.91% (23/258).The positive rates of G.duodenalis in cattle from different regions were extremely significantly different (P<0.01),with the highest positive rate in Heqing county,Dali,at 20.75% (11/53,95% CI=9.47-32.04),the positive rates of Menghai county in Xishuangbanna and Yongshan county in Zhaotong were 8.82% (6/68,95% CI=1.91-15.74) and 4.38% (6/137,95% CI=0.91-7.85),respectively.The positive rates of G.duodenalis in cattle of different ages were extremely significantly different (P<0.01).The positive rate in calves (<5 months old) (26.19%,11/42,95% CI=12.32-40.06) was extremely significantly higher than that in adult cattle (>24 months old) (5.56%,12/216,95% CI=2.48-8.64).There was an extremely significant difference in the positive rate of G.duodenalis among different breeds of cattle (P<0.01).Holstein cows had the highest positive rate of G.duodenalis,which was 20.75% (11/53,95% CI=12.00-39.17).Yellow cattle,Western crossbred cattle (a hybrid of Simmental cattle and local Yellow cattle),and Simmental cattle had lower positive rates,which were 17.86% (5/28,95% CI=2.73-32.98),4.38% (6/137,95% CI=0.91-7.85) and 2.50% (1/40,95% CI=0-7.56),respectively.Based on the analysis of gdh gene sequence,23 positive samples of G.duodenalis were all assemblage E,but with 7 different subtypes.Among them,6 subtypes had a similarity of 99.8% to 100% with known reference sequences (E1,E12,E20,E30,E36 and E38),and another subtype had a similarity of 99.8% with unnamed reference sequences.【Conclusion】 Cattle in Yunnan province were infected with G.duodenalis,with the positive infection rate varying with different regions,ages,and breeds of cattle.Assemblage E dominated the assemblages of G.duodenalis infection in cattle of Yunnan province,which possessed rich genetic diversity in Yunnan province.

Key words: cattle; Giardia duodenalis; gdh gene; genotype

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