Mycotic abortion is an important reproductive problem among farm animals throughout the world. The secondary complications such as retention of placenta, endometritis, infertility, sterility, pyometra and delayed conception may developed and sometimes death of animals may occur, causes greater economic loss. The clinical symptoms of affected animal show foul smelling vaginal discharge, hyperemia of cervical mucosa, reduced appetite, high body temperature and retention of placenta. The placentas in most of the aborted cases become thickened, necrotic, hemorrhagic and edematous. The aborted fetus shows a discrete, raised lesion on the skin of the head and neck, generalized fetal edema and pneumonic changes of lungs.
       
The fungal infections mainly occur during the winter and hot humid season due to high amount of moisture content in the environment.  The pregnant animals exposed into a fungal infection, the conidia of fungus, able to penetrate lesions present in the gastrointestinal or respiratory tract and spread throughout the body via blood and reach the placenta and the foetus. The uterine environment creates favourable condition for the full development of the fungus and establishment of fungal colonies. The mycotic abortion generally occur last trimester of pregnancy leads to retention of the placenta. The hemorrhagic necrotizing placentitis is commonly found in aborted animals placenta associated with necrotic, thick and yellow cotyledons. The parakeratotic dermatitis seen on the skin surface of aborted foetus characterized by raised plaques and blepharitis. The diagnosis of mycotic abortion in animals mainly based on clinical examination, macroscopic evaluation, histological examination of aborted foetus and placenta, culture isolation of fungal species from placenta of aborted animals and the abomasal contents of aborted foetus. The Aspergillus fumigatus, Aspergillus nidulans, Absidia corymbifera and Mortierella wolfii are isolated from aborted foetuses and species in the genera Rhizopus, Mucor and Rhizomucor,,  Geotrichum spp. are ubiquitous saprotrophic fungi commonly found in soil, decomposing organic matter, food products and the digestive tracts of mammals and these species will causes abortion in human. The Geotrichum candidum infection causes severe skin lesions in horses and the G. candidum commonly isolated from the reproductive tracts of cows and buffalo with and without reproductive problems.

The research work was done in Central University Laboratory, Madhavaram Milk Colony, TANUVAS, Chennai-51 for the period of 2022-2024. A total of 56 samples were collected from 22 aborted dogs and aborted fetus, placenta and endometrial exudates from suspected cases were collected (Fig 1 and 2). The mother’s serum samples were collected for detection of for Brucella antibody by RBPT and ELISA. Samples like abomasal contents, liver, lung and skin were collected from aborted foetus aseptically and submitted for aerobic and microaerobic bacterial isolation. The brain-heart infusion agar medium was used for isolation of Campylobacter spp. and Brucella isolation agar was used for selective isolation of Brucella spp., from aborted materials. Screening of bacterial viral and haemoprotozoan diseases were performed with all the aborted samples. The aborted materials were cultured in sabouraud dextrose agar medium (Himedia) supplemented with chloramphenicol with the incubation period of 7-10 days in a controlled temperature range of 25-27°C. The morphological identification of fungus mainly based on growth pattern, colour of the colonies and microscopic analysis of the fungal hyphae present with lactophenol cotton blue staining technique (Fig 7 and Fig 8).

The 56 numbers of aborted dog’s placenta, fetus and vaginal discharge from different breeds were collected from different parts of Tamil Nadu and subjected to culture isolation and identification by using specific media. The serum samples were collected from a suspected mother shows negative results in RBPT and ELISA. The 5 dog’s aborted samples showed positive for Klebsiella and Staphylococcus and 7 dog’s aborted samples showed E. coli and 12 dogs Candida albicans were isolated. The Aspergillus fumicatus were isolated from all the dog’s aborted materials which are mostly distributed in the environment (Table 1; Fig 1,2,3,4,5,6,7 and 8). All the aborted samples were negative for HPD, Cryptococcus, Leptospirosis, CD, CPV and Brucellosis by PCR.


















       
Mycotic abortion among animals causes severe reproductive problem and economic loss. The infectious and non-infectious factors may plays a significant role for foetal abortion and infertility in farm animals (Gojam and Tulu, 2020). The infectious microbes such as a bacteria, virus, fungus or protozoa were constituted a significant level of abortion in animals (Hajibemani and Sheikhalislami, 2020; Parthiban et al., 2015; Shaapan, 2016). Approximately 50%-62% of foetal abortions are caused by bacteria, 22%-25% of abortion caused by fungi and 15%-25% of abortion caused by viruses in dairy cows and other livestock (Pal, 2015). The non-infectious factors, like nutrition, chemicals, drugs, toxins, poisonous plants and hormonal imbalances also significantly cause foetal abortion among animals (Yadav et al., 2021). In case of  uterine infections, major infection considered as endometritis which was recorded as highest (34.16%) followed by pyometra (18.33%), cervicitis (10.00%) and abortion (3.33%). The haematological study revealed a significant decrease in haemoglobin and total erythrocyte count while a significant increase in total leukocyte count in animals with uterine infection as compared to the control group and the biochemical study revealed that there was a severe decrease in serum glucose and serum cholesterol level in uterine infected cows in comparison to healthy cows (Sarkar et al., 2016).
       
Deori et al., (2019) studied the epidemiology of abortion in yaks managed under farm condition in semi-intensive system of management.  They found the overall incidence of abortion was 16.54% out of which 80.95% abortions were recorded in pleuriparous and 19.05% in the primiparous animals and the month wise analysis showed that maximum abortions were recorded in the month of June followed by May. They found that maximum abortions were recorded during the late gestation phase followed by mid gestation and early gestation stage.
       
Mishra et al., (2024) studied the occurrence of abortion in goats (combined farm) association with seasons and stages of pregnancy, they found that the abortion had a significantly associated with season and not associated with parities. They found that the Barbari, Jakharana and Jamunapari goats individually showed significant differences in abortion rates across various seasons, but did not exhibit significant variation in abortion rates with respect to different stages of pregnancy or parities. In the study, they found that the majority of abortions occur in the winter season, followed by the rainy and summer seasons. similarly, most of the abortions were noticed in the later stage of pregnancy, followed by the mid- and early stages. There was the highest abortion rate in the goats with parity 3 and above, followed by the first and second parities.
       
Mycotic abortions are mainly caused by moulds and yeasts. The inflammation of the placenta mainly associated with infection by bacteria and fungi (Borel et al., 2014; Jaiswal et al., 2019). Totally 35 different fungal species causing mycotic abortion in farm animals (Van Kuijk et al., 2015). Approximately 60% of mycotic abortion among animals caused by Aspergillus fumigatus and 20% of fungal abortion caused by Zygomycetes such as Absidia, Mucor, Rhizomucor, Geotrichum, Rhizopus and yeasts infection cause 20% abortion in cattle (Hajibemani and Sheikhalislami, 2020; Negi et al., 2024; Pal, 2015; Parthiban et al., 2015). Mainly placenta, amniotic fluid, lung and stomach content of aborted foetus used for isolation of fungus (Elad and Segal, 2018; Reichel et al., 2018). The total 56 samples of aborted foetus vaginal discharge and placenta were collected from 22 aborted dogs throughout Tamil Nadu. The mycological examination of aborted foeti, vaginal discharge and placenta of aborted dogs showed the A. fumigatus, Aspergillus niger, Aspergillus flavus, C. albicans, C. tropicalis, C. krusei and bacteria like Klebsiella, E.coli, Staphylococcus also isolated in aborted materials (Table 1.)
       
The diagnosis of mycotic abortion involves both the conventional culture and microscopic observation of fungal hyphae and fungal spore along with gross lesions (Vidal et al., 2018). The molecular confirmation may perform with fungal DNA in the aborted materials and mycotic abortion diagnostic workflow should always include other abortifacients and histopathological examination of fungal infected tissues. The fungal organism mainly present in large numbers on the foetal abomasum, foetal tissues and placenta. A combined approaches needed for  diagnosis, prevention and development of mitigation strategy of foetal abortion in farm animals. (Fatima, 2021; Mostrom and Jacobsen, 2020).

The fungal abortions in dogs occurs usually between 30-40 days of gestation and particularly in hot humid summer months. The closed confinement of pregnant animals in humid, hot and unhygienic houses is the main predisposing factor for mycotic abortion. So proper environmental management must be provided for dogs and the pet owner may advised to avoid moldy food and improperly stored processed food particularly in pregnant bitches. The clinical examination of male breeding dogs before crossing will be recommended and adequate nutritional supplements and proper environment will improve the host immunity to avoid mycotic abortion in dogs. The transmission pattern and epidemiological surveillance of fungal abortion are still not explored completely. The direct microscopy examination of skin scrapping and hairs and cultural isolation of the fungal agent in the clinical specimen are still considered as the main method of diagnosis of fungus. Currently, no treatment protocol has been evolved for mycotic abortion in dogs.  Future research studies needed on the pathogenesis and epidemiological patterns of fungal abortion in dogs and the application of molecular techniques for quick diagnosis of mycotic abortion in dogs to start early appropriate treatment.

The present research work carried out at Central University Laboratory, Centre for Animal Health Studies, TANUVAS, Chennai.
 
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