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Full Research Article

Serological and Molecular Identification of Mycoplasma Infection in Goats and Sheep of Northern India

A
Anil Kumar Mishra1
M
Manish Kushwah1,*
A
Ashish Kumar Churamani1
K
K. Gururaj1
N
Nitika Sharma1
1Animal Health Division, ICAR-Central, Institute for Research on Goats (ICAR-CIRG), Farah-281 122, Mathura, Uttar Pradesh, India.

ABSTRACT

Background: Mycoplasmosis is an important infectious disease in small ruminants and causes fever, weakness, drop in milk yield and many times animals become long-term carriers that keep spreading the infection within and even between the flocks. The aim of the study was to assess Mycoplasma infection in goats and sheep by using both quick field test and lab-based molecular method.

Methods: A total of 730 serum samples were collected from goats raised at organized farms as well as from local field conditions in different parts of Uttar Pradesh and Rajasthan. These samples were tested by slide agglutination test (SAT) using a colored Mycoplasma antigen obtained from ICAR-IVRI, Izatnagar. Additionally, 354 biological samples including nasal secretions, pneumonic lung tissues, reproductive discharges and fetal contents from goats and sheep were examined by polymerase chain reaction (PCR) employing genus and species-specific primers.

Result: Out of 730 serum samples, 32 samples (4.38%) were found positive in the slide agglutination test (SAT). Out of 58 DNA samples from nasal and lung tissues, 14 tested positive for the Mycoplasma genus, with one case each confirming Mycoplasma agalactiae and Mycoplasma capricolum subsp. capripneumoniae. None tested positive for M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginini, or M. ovipneumoniae. Among 296 DNA samples from reproductive sources, 84 were positive at the genus level. None of these 84 samples tested positive for the targeted species. These findings show that Mycoplasma infection is quite common and that using both serological and molecular tests together gives a clearer and more reliable picture for disease prevention and control planning.

INTRODUCTION

Mycoplasmas are the smallest free living organisms classified within the class Mollicutes and are pleomorphic in nature (Ponnusamy et al., 2019). There are several Mycoplasma species that are known to cause serious health problems in small ruminants (Nicholas et al., 2009). The most important among these include M. capricolum subsp. capripneumoniae, Mycoplasma agalactiae, M. capricolum subsp. capricolum, M. mycoides subsp. capri, M. putrafaciens, M. arginini, M. ovipneumoniae and M. conjunctiviae (Nicholas et al., 2008; Thiaucourt and Bölske, 1996; OIE, 2021). These organisms exhibit a marked tropism for specific tissues and predominantly affect particular organ systems such as the mammary glands, joints, eyes, respiratory tract and reproductive organs (OIE, 2021; Corrales et al., 2007; Kumar et al., 2019). Mycoplasma agalactiae primarily affects the mammary glands, joints and eyes and may occasionally involve in the reproductive and respiratory tracts, leading to clinical manifestations such as mastitis, arthritis and keratoconjunctivitis (Birben, 2022). In contrast, M. capricolum subsp. capripneumoniae, the causative agent of contagious caprine pleuropneumonia (CCPP), specifically affects the lungs and pleura, leading to fibrinous pleuropneumonia and respiratory distress (Shanmugavadivu et al., 2023). Both species exhibit tissue tropism and evade host immunity via antigenic variation (Nicholas et al., 2008; OIE, 2021; Corrales et al., 2007). Mycoplasma capricolum subsp. capricolum (Mcc) mainly affects goats and occasionally sheep, causing polyarthritis, mastitis, mild pneumonia, pleuritis and sometimes septicemia in kids. Mycoplasma mycoides subsp. capri (Mmc) primarily affects goats and occasionally sheep, causing pleuropneumonia, arthritis, mastitis, conjunctivitis and septicemia in kids and it targets the respiratory tract, joints, mammary glands and eyes (Nicholas et al., 2008; OIE, 2021).
       
Molecular tools like polymerase chain reaction (PCR) are routinely used for rapidly and accurately detecting Mycoplasma at both the genus and species levels (Kumar et al., 2011). Likewise, simple serological tests like the slide agglutination test are also a quick and reliable way to screen and monitor animals on-site, especially in the field (Manimaran et al., 2021). Hence, these tests were used in the current study to detect mycoplasmal infections in goats and sheep.
       
The objectives of the current study were to use PCR to find Mycoplasma at both the genus and species levels in different biosamples from goat and sheep and to find out how common these infections are in goat populations by using a simple, field-based slide agglutination test with coloured antigen. The present study will help us in devising better ways to monitor and control the disease in small ruminant farming.

MATERIALS AND METHODS

Sample collection
 
The study was carried out at the ICAR-Central Institute for Research on Goats (ICAR-CIRG), Makhdoom, Mathura, Uttar Pradesh, India.  A total of 730 serum samples were collected from goats raised in both organized farm conditions and field conditions in various regions of Uttar Pradesh and Rajasthan. For the PCR-based molecular diagnosis, a total of 354 bio-samples were collected from goats and sheep in various regions of Uttar Pradesh and Rajasthan. Of the total samples, 58 were derived from nasal secretions and pneumonic lung tissues, whereas 296 originated from reproductive sources, including preputial and vaginal swabs, fetal stomach contents and placental tissues.
 
Serological testing: Slide agglutination test (SAT)
 
Antibodies against Mycoplasma spp. in goat sera were detected using the slide agglutination test (SAT) with a colored antigen. The antigen was obtained from the Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar. The 10 µL of colored antigen was mixed with same volume of goat serum on the clean grease-free glass slide. After combining both components, the mixture was mixed thoroughly using a sterile toothpick and given gentle rocking for one to two minutes. The results of slide agglutination test were read after a period of one minute; if visible clumping appeared, it was considered a positive reaction indicating that antibodies are present and if no such clumping appeared, it was recorded as a negative response.
 
DNA extraction
 
Genomic DNA was extracted from all biosamples using standard phenol-chloroform extraction and commercial DNA isolation kit (DNASure® Tissue Mini Kit, Genetics Biotech Asia Ltd.). The quality and concentration of the extracted DNA were assessed using agarose gel electrophoresis and spectrophotometric analysis.
 
Polymerase chain reaction (PCR)
 
The DNA samples that tested positive at the genus level were further subjected to species-specific polymerase chain reaction (PCR) assays. These assays were designed to detect eight Mycoplasma species of veterinary importance, including Mycoplasma agalactiae, Mycoplasma capricolum subsp. capripneumoniae, Mycoplasma mycoides subsp. capri, Mycoplasma capricolum subsp. capricolum, Mycoplasma putrefaciens, Mycoplasma conjunctivae, Mycoplasma arginini and Mycoplasma ovipneumoniae. Every PCR reaction was carried out in a total volume of 25 µL containing 12.5 µL of PCR Master Mix, 1 µL of forward and reverse primers each, 2 µL of DNA template and nuclease-free water to complete the final volume. The details of the primer sets and the thermal cycling conditions are given below in Table 1 and 2, respectively. The conditions differed according to the target organism and the primer set (Table 1), with optimized denaturation, annealing and extension steps to amplify the preferred product sizes from 192 to 748 bp. The amplified PCR products were electrophoresed on 1.5% agarose gels stained with ethidium bromide and visualized under UV transillumination. Band sizes were referenced to a 100 bp DNA ladder to identify species-specific amplification. Results were evaluated on the basis of the appearance of anticipated amplicon sizes, with samples with no amplification being regarded as negative for the species.

Table 1: Primer sets used in the PCR identification of different Mycoplasma spp.



Table 2: Cycling conditions used for PCR-based identification of various Mycoplasma spp.

RESULTS AND DISCUSSION

Mycoplasma infections are among the most challenging diseases affecting small ruminants, causing significant economic losses either as primary pathogens or in combination with other respiratory agents. This study investigates the detection of various Mycoplasma species across diverse biological specimens and evaluates the seroprevalence of mycoplasmosis. Serological analysis revealed a 4.38% seropositivity rate within the tested population of goats (n = 730). This finding is in close agreement with the results of Ramdeva et al., (2008) from Himachal Pradesh, who reported a seroprevalence of 4.77% in sheep and goats using the slide agglutination test. Such similarity indicates a comparable level of endemicity in both regions despite geographical differences. However, the present prevalence was found to be much lower than that reported in Madhya Pradesh by Gupta et al., (2016) who recorded an overall seropositivity of 10.65% in goats. The higher prevalence in their study may be attributed to factors such as intensive management practices in organized farms, closer animal contact facilitating transmission and possible interstate livestock movement which enhances exposure to infection. Similarly, a considerably higher prevalence was documented in Tamil Nadu by Rishikesavan et al. (2020), with 25.40% in unorganized and 28.68% in organized goat farms using iELISA. The variation from the present findings could be explained by differences in diagnostic methodology (iELISA being more sensitive than slide agglutination), agro-climatic conditions favoring disease spread and introduction of exotic breeds, which may increase susceptibility to Mycoplasma infections. These results indicate prior exposure or latent infection in a subset of the goat population, supporting that Mycoplasma infections are endemic but not widespread in the sampled regions. The seropositivity, although low, underscores the importance of continued surveillance and implementation of molecular diagnostics for early detection and effective management of Mycoplasma-associated diseases in caprine herds.
       
The detection and characterization of Mycoplasma spp. infections in goats were carried out using molecular approach (PCR). The DNAs extracted from nasal secretions and pneumonic lung tissues (n=58) were subjected to genus-specific PCR targeting a conserved 270 bp region common to Mycoplasma spp. The analysis revealed that 14 out of 58 samples (24.1%) were positive for the Mycoplasma genus (Fig 1). Subsequently, species-specific PCR assays were performed on these 14 genus-positive samples to determine the involvement of specific pathogenic species. Among them, one sample was positive for Mycoplasma agalactiae (Fig 2), the etiological agent of contagious agalactia in goats, while another tested positive for Mycoplasma capricolum subsp. capripneumoniae (Fig 3), a highly contagious pathogen responsible for contagious caprine pleuropneumonia. However, none of the remaining genus-positive samples (n=12) showed amplification for M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginine, or M. ovipneumoniae, indicating the absence of these species or possibly the presence of uncharacterized strains not targeted by the selected primers.

Fig 1: Molecular identification of Mycoplasma spp.



Fig 2: Molecular identification of Mycoplasma agalactiae.



Fig 3: Molecular identification of M. capricolum ss. capripneumoniae.


       
In a parallel investigation targeting the reproductive tract and fetal-associated tissues, 296 DNAs were extracted from preputial and vaginal secretions, fetal stomach contents and placental tissues. Genus-specific PCR screening revealed that 84 out of 296 samples (28.4%) were positive for Mycoplasma spp. These 84 positive samples were subjected to the same panel of species-specific PCR assays to identify known Mycoplasma pathogens. Interestingly, none of these samples tested positive for any of the targeted species including M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginini and M. ovipneumoniae. 
       
Out of a total of 354 biological samples collected from respiratory (n=58) and genital (n=296) sources, Mycoplasma spp. were detected in 27.68% of the samples (98/354) screened. This confirmed the presence of Mycoplasma DNA in a notable number of the animals. This detection rate aligns with the observations of Lin et al., (2022), who documented the positivity ranged from 8.20% to 24.59% among goats. Jain et al., (2015) reported a lower prevalence of Mycoplasma spp. (8.11%), which contrasts with the higher prevalence observed in our study. The restricted diversity may be due to predominance of genital samples, host factors, or uncharacterized Mycoplasma strains. The detection of M. capricolum subsp. capripneumoniae is particularly important as it is an OIE-listed transboundary pathogen with high economic impact (World Organisation for Animal Health, 2021). The low detection of Mycoplasma agalactiae agrees with Kumar et al., (2014), who documented sporadic occurrences. The absence of Mycoplasma mycoides subsp. capri may reflect regional variation or effective control measures, supported by Dudek et al., (2022), who reported declining trends in areas with strong vaccination programs and biosecurity practices.

CONCLUSION

In conclusion, this study highlights the ongoing problem of Mycoplasma spp. in goats. The detection of M. agalactiae and Mycoplasma capricolum ss. capripneumoniae shows their ongoing threat in endemic areas. Molecular and serological monitoring, early diagnosis and targeted vaccination are crucial for managing Mycoplasma diseases. Future research should explore co-infections with other pathogens, resistance to antibiotics and long-term disease tracking using advanced genomic methods.

ACKNOWLEDGEMENT

The research work was conducted under the All India Network Project on “Challenging and Emerging Diseases in Animals (Goat and Sheep Mycoplasmosis).” The authors gratefully acknowledge the Indian Council of Agricultural Research, New Delhi, for funding support and the Director, ICAR-Central Institute for Research on Goats, Makhdoom, Farah-281122, Mathura, Uttar Pradesh, for providing the necessary facilities to carry out this study.
 
Animal ethics statement
 
The sample collection was carried out in accordance with established ethical guidelines and approval was obtained from the Institutional Animal Ethics Committee.

CONFLICT OF INTEREST

The authors have no conflicts of interest to disclose.

REFERENCES


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    Full Research Article

    Serological and Molecular Identification of Mycoplasma Infection in Goats and Sheep of Northern India

    A
    Anil Kumar Mishra1
    M
    Manish Kushwah1,*
    A
    Ashish Kumar Churamani1
    K
    K. Gururaj1
    N
    Nitika Sharma1
    1Animal Health Division, ICAR-Central, Institute for Research on Goats (ICAR-CIRG), Farah-281 122, Mathura, Uttar Pradesh, India.

    ABSTRACT

    Background: Mycoplasmosis is an important infectious disease in small ruminants and causes fever, weakness, drop in milk yield and many times animals become long-term carriers that keep spreading the infection within and even between the flocks. The aim of the study was to assess Mycoplasma infection in goats and sheep by using both quick field test and lab-based molecular method.

    Methods: A total of 730 serum samples were collected from goats raised at organized farms as well as from local field conditions in different parts of Uttar Pradesh and Rajasthan. These samples were tested by slide agglutination test (SAT) using a colored Mycoplasma antigen obtained from ICAR-IVRI, Izatnagar. Additionally, 354 biological samples including nasal secretions, pneumonic lung tissues, reproductive discharges and fetal contents from goats and sheep were examined by polymerase chain reaction (PCR) employing genus and species-specific primers.

    Result: Out of 730 serum samples, 32 samples (4.38%) were found positive in the slide agglutination test (SAT). Out of 58 DNA samples from nasal and lung tissues, 14 tested positive for the Mycoplasma genus, with one case each confirming Mycoplasma agalactiae and Mycoplasma capricolum subsp. capripneumoniae. None tested positive for M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginini, or M. ovipneumoniae. Among 296 DNA samples from reproductive sources, 84 were positive at the genus level. None of these 84 samples tested positive for the targeted species. These findings show that Mycoplasma infection is quite common and that using both serological and molecular tests together gives a clearer and more reliable picture for disease prevention and control planning.

    INTRODUCTION

    Mycoplasmas are the smallest free living organisms classified within the class Mollicutes and are pleomorphic in nature (Ponnusamy et al., 2019). There are several Mycoplasma species that are known to cause serious health problems in small ruminants (Nicholas et al., 2009). The most important among these include M. capricolum subsp. capripneumoniae, Mycoplasma agalactiae, M. capricolum subsp. capricolum, M. mycoides subsp. capri, M. putrafaciens, M. arginini, M. ovipneumoniae and M. conjunctiviae (Nicholas et al., 2008; Thiaucourt and Bölske, 1996; OIE, 2021). These organisms exhibit a marked tropism for specific tissues and predominantly affect particular organ systems such as the mammary glands, joints, eyes, respiratory tract and reproductive organs (OIE, 2021; Corrales et al., 2007; Kumar et al., 2019). Mycoplasma agalactiae primarily affects the mammary glands, joints and eyes and may occasionally involve in the reproductive and respiratory tracts, leading to clinical manifestations such as mastitis, arthritis and keratoconjunctivitis (Birben, 2022). In contrast, M. capricolum subsp. capripneumoniae, the causative agent of contagious caprine pleuropneumonia (CCPP), specifically affects the lungs and pleura, leading to fibrinous pleuropneumonia and respiratory distress (Shanmugavadivu et al., 2023). Both species exhibit tissue tropism and evade host immunity via antigenic variation (Nicholas et al., 2008; OIE, 2021; Corrales et al., 2007). Mycoplasma capricolum subsp. capricolum (Mcc) mainly affects goats and occasionally sheep, causing polyarthritis, mastitis, mild pneumonia, pleuritis and sometimes septicemia in kids. Mycoplasma mycoides subsp. capri (Mmc) primarily affects goats and occasionally sheep, causing pleuropneumonia, arthritis, mastitis, conjunctivitis and septicemia in kids and it targets the respiratory tract, joints, mammary glands and eyes (Nicholas et al., 2008; OIE, 2021).
           
    Molecular tools like polymerase chain reaction (PCR) are routinely used for rapidly and accurately detecting Mycoplasma at both the genus and species levels (Kumar et al., 2011). Likewise, simple serological tests like the slide agglutination test are also a quick and reliable way to screen and monitor animals on-site, especially in the field (Manimaran et al., 2021). Hence, these tests were used in the current study to detect mycoplasmal infections in goats and sheep.
           
    The objectives of the current study were to use PCR to find Mycoplasma at both the genus and species levels in different biosamples from goat and sheep and to find out how common these infections are in goat populations by using a simple, field-based slide agglutination test with coloured antigen. The present study will help us in devising better ways to monitor and control the disease in small ruminant farming.

    MATERIALS AND METHODS

    Sample collection
     
    The study was carried out at the ICAR-Central Institute for Research on Goats (ICAR-CIRG), Makhdoom, Mathura, Uttar Pradesh, India.  A total of 730 serum samples were collected from goats raised in both organized farm conditions and field conditions in various regions of Uttar Pradesh and Rajasthan. For the PCR-based molecular diagnosis, a total of 354 bio-samples were collected from goats and sheep in various regions of Uttar Pradesh and Rajasthan. Of the total samples, 58 were derived from nasal secretions and pneumonic lung tissues, whereas 296 originated from reproductive sources, including preputial and vaginal swabs, fetal stomach contents and placental tissues.
     
    Serological testing: Slide agglutination test (SAT)
     
    Antibodies against Mycoplasma spp. in goat sera were detected using the slide agglutination test (SAT) with a colored antigen. The antigen was obtained from the Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar. The 10 µL of colored antigen was mixed with same volume of goat serum on the clean grease-free glass slide. After combining both components, the mixture was mixed thoroughly using a sterile toothpick and given gentle rocking for one to two minutes. The results of slide agglutination test were read after a period of one minute; if visible clumping appeared, it was considered a positive reaction indicating that antibodies are present and if no such clumping appeared, it was recorded as a negative response.
     
    DNA extraction
     
    Genomic DNA was extracted from all biosamples using standard phenol-chloroform extraction and commercial DNA isolation kit (DNASure® Tissue Mini Kit, Genetics Biotech Asia Ltd.). The quality and concentration of the extracted DNA were assessed using agarose gel electrophoresis and spectrophotometric analysis.
     
    Polymerase chain reaction (PCR)
     
    The DNA samples that tested positive at the genus level were further subjected to species-specific polymerase chain reaction (PCR) assays. These assays were designed to detect eight Mycoplasma species of veterinary importance, including Mycoplasma agalactiae, Mycoplasma capricolum subsp. capripneumoniae, Mycoplasma mycoides subsp. capri, Mycoplasma capricolum subsp. capricolum, Mycoplasma putrefaciens, Mycoplasma conjunctivae, Mycoplasma arginini and Mycoplasma ovipneumoniae. Every PCR reaction was carried out in a total volume of 25 µL containing 12.5 µL of PCR Master Mix, 1 µL of forward and reverse primers each, 2 µL of DNA template and nuclease-free water to complete the final volume. The details of the primer sets and the thermal cycling conditions are given below in Table 1 and 2, respectively. The conditions differed according to the target organism and the primer set (Table 1), with optimized denaturation, annealing and extension steps to amplify the preferred product sizes from 192 to 748 bp. The amplified PCR products were electrophoresed on 1.5% agarose gels stained with ethidium bromide and visualized under UV transillumination. Band sizes were referenced to a 100 bp DNA ladder to identify species-specific amplification. Results were evaluated on the basis of the appearance of anticipated amplicon sizes, with samples with no amplification being regarded as negative for the species.

    Table 1: Primer sets used in the PCR identification of different Mycoplasma spp.



    Table 2: Cycling conditions used for PCR-based identification of various Mycoplasma spp.

    RESULTS AND DISCUSSION

    Mycoplasma infections are among the most challenging diseases affecting small ruminants, causing significant economic losses either as primary pathogens or in combination with other respiratory agents. This study investigates the detection of various Mycoplasma species across diverse biological specimens and evaluates the seroprevalence of mycoplasmosis. Serological analysis revealed a 4.38% seropositivity rate within the tested population of goats (n = 730). This finding is in close agreement with the results of Ramdeva et al., (2008) from Himachal Pradesh, who reported a seroprevalence of 4.77% in sheep and goats using the slide agglutination test. Such similarity indicates a comparable level of endemicity in both regions despite geographical differences. However, the present prevalence was found to be much lower than that reported in Madhya Pradesh by Gupta et al., (2016) who recorded an overall seropositivity of 10.65% in goats. The higher prevalence in their study may be attributed to factors such as intensive management practices in organized farms, closer animal contact facilitating transmission and possible interstate livestock movement which enhances exposure to infection. Similarly, a considerably higher prevalence was documented in Tamil Nadu by Rishikesavan et al. (2020), with 25.40% in unorganized and 28.68% in organized goat farms using iELISA. The variation from the present findings could be explained by differences in diagnostic methodology (iELISA being more sensitive than slide agglutination), agro-climatic conditions favoring disease spread and introduction of exotic breeds, which may increase susceptibility to Mycoplasma infections. These results indicate prior exposure or latent infection in a subset of the goat population, supporting that Mycoplasma infections are endemic but not widespread in the sampled regions. The seropositivity, although low, underscores the importance of continued surveillance and implementation of molecular diagnostics for early detection and effective management of Mycoplasma-associated diseases in caprine herds.
           
    The detection and characterization of Mycoplasma spp. infections in goats were carried out using molecular approach (PCR). The DNAs extracted from nasal secretions and pneumonic lung tissues (n=58) were subjected to genus-specific PCR targeting a conserved 270 bp region common to Mycoplasma spp. The analysis revealed that 14 out of 58 samples (24.1%) were positive for the Mycoplasma genus (Fig 1). Subsequently, species-specific PCR assays were performed on these 14 genus-positive samples to determine the involvement of specific pathogenic species. Among them, one sample was positive for Mycoplasma agalactiae (Fig 2), the etiological agent of contagious agalactia in goats, while another tested positive for Mycoplasma capricolum subsp. capripneumoniae (Fig 3), a highly contagious pathogen responsible for contagious caprine pleuropneumonia. However, none of the remaining genus-positive samples (n=12) showed amplification for M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginine, or M. ovipneumoniae, indicating the absence of these species or possibly the presence of uncharacterized strains not targeted by the selected primers.

    Fig 1: Molecular identification of Mycoplasma spp.



    Fig 2: Molecular identification of Mycoplasma agalactiae.



    Fig 3: Molecular identification of M. capricolum ss. capripneumoniae.


           
    In a parallel investigation targeting the reproductive tract and fetal-associated tissues, 296 DNAs were extracted from preputial and vaginal secretions, fetal stomach contents and placental tissues. Genus-specific PCR screening revealed that 84 out of 296 samples (28.4%) were positive for Mycoplasma spp. These 84 positive samples were subjected to the same panel of species-specific PCR assays to identify known Mycoplasma pathogens. Interestingly, none of these samples tested positive for any of the targeted species including M. mycoides subsp. capri, M. capricolum subsp. capricolum, M. putrefaciens, M. conjunctivae, M. arginini and M. ovipneumoniae. 
           
    Out of a total of 354 biological samples collected from respiratory (n=58) and genital (n=296) sources, Mycoplasma spp. were detected in 27.68% of the samples (98/354) screened. This confirmed the presence of Mycoplasma DNA in a notable number of the animals. This detection rate aligns with the observations of Lin et al., (2022), who documented the positivity ranged from 8.20% to 24.59% among goats. Jain et al., (2015) reported a lower prevalence of Mycoplasma spp. (8.11%), which contrasts with the higher prevalence observed in our study. The restricted diversity may be due to predominance of genital samples, host factors, or uncharacterized Mycoplasma strains. The detection of M. capricolum subsp. capripneumoniae is particularly important as it is an OIE-listed transboundary pathogen with high economic impact (World Organisation for Animal Health, 2021). The low detection of Mycoplasma agalactiae agrees with Kumar et al., (2014), who documented sporadic occurrences. The absence of Mycoplasma mycoides subsp. capri may reflect regional variation or effective control measures, supported by Dudek et al., (2022), who reported declining trends in areas with strong vaccination programs and biosecurity practices.

    CONCLUSION

    In conclusion, this study highlights the ongoing problem of Mycoplasma spp. in goats. The detection of M. agalactiae and Mycoplasma capricolum ss. capripneumoniae shows their ongoing threat in endemic areas. Molecular and serological monitoring, early diagnosis and targeted vaccination are crucial for managing Mycoplasma diseases. Future research should explore co-infections with other pathogens, resistance to antibiotics and long-term disease tracking using advanced genomic methods.

    ACKNOWLEDGEMENT

    The research work was conducted under the All India Network Project on “Challenging and Emerging Diseases in Animals (Goat and Sheep Mycoplasmosis).” The authors gratefully acknowledge the Indian Council of Agricultural Research, New Delhi, for funding support and the Director, ICAR-Central Institute for Research on Goats, Makhdoom, Farah-281122, Mathura, Uttar Pradesh, for providing the necessary facilities to carry out this study.
     
    Animal ethics statement
     
    The sample collection was carried out in accordance with established ethical guidelines and approval was obtained from the Institutional Animal Ethics Committee.

    CONFLICT OF INTEREST

    The authors have no conflicts of interest to disclose.

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