Infertility in Female Buffaloes Due to Some Uterine Disorders

The current world buffalo population is about 200 million (Hegde, 2019). More than 97 % of the world’s population of water buffalo is kept in Asia. The uterine infertility in dairy animals is various and may be attributed to a number of conditions like hormonal disturbances, infectious diseases, nutritional causes, congenital and other pathological conditions. Among the most possible causes, uterine abnormalities were considered as one of the major causes like perimetritis, adenomyosis, hydrometera, mucometra, endometritis, pyometra, perimetritis and serositis. Out of the total affected buffaloes, the incidence of perimetritis was the highest (10.7%) followed by endometritis (7.14%), perimetrial cyst (5.35%), adenomyosis (3.57%) and pyometra (3.57%), hydrometra (1.78%), mucometra (1.78%) and serositis (1.78%) (Mittal et al., 2009; Ponraj et al., 2017; Hamouda et al., 2020; Kumar et al., 2022). The fertility of buffaloes still low due to bad nutrition, management and other environmental factors (Pasha and Hayat, 2012). The rate of uterine infection in buffaloes is more than in cows (Azawi, 2010). Endometritis have been reported previously in buffaloes (Dawar et al., 2017; Babji et al., 2020; Elmetwally et al., 2020, Hamouda et al., 2020). Postpartum metritis is a major disorders in buffaloes leading to a fetid vulvar discharge and uterine infections can be life-threatening, leading to prolonged inter calving intervals and involuntary culling (Azawi et al., 2013). Bacterial species are involved in most cases of endometritis and in some cases fungal infection was recorded due to the irrational use of antibiotics (Shokri and Yadollahi, 2017; Rashid et al., 2020). Subclinical endometritis in buffaloes is a main cause of infertility and represents a major role of repeat breeding syndrome in dairy animals (Elsayed et al., 2020; Singh et al., 2020). A repeat breeder is animal fails to conceive after three services associated with true oestrus. There are a number of factors impicated in this condition. In general, uterine infections together with anoestrus and environmental factors are the main causes (Saraswat and Purohit, 2016). In buffloes, failure of fertilization and early embryonic death has also been considered (Mohyuddin et al., 2019). There are different diagnostic techniques for the diagnosis of subclinical endometritis including biopsy, endometrial cytology, ultrasonography and vaginoscopy (Singh et al., 2020; Parikh et al., 2022).Uterine tumours are very few and rare among dairy animals. However, leiomyomas are the most common tumour among cattle and buffaloes (Sachan et al., 2018; Azawi and Al-Sadi, 2010). In a conclusion, the present study clarified that uterine disorders play a major role in female buffaloes infertility.

Uteri of 340 of buffaloes (3-6 years) with a history of infertility have been collected from different farms in Egypt for a period of two years (2021-2022).

A gross inspection of the body of the uterus and two horns was performed for any external abnormalities. Endometrium was examined for colour, the nature of the fluid, and any internal lesions. Specimens from affected parts were collected and fixed in neutral buffered formalin (10%).The specimens were processed, embedded in paraffin, sectioned at 3-5 um, and stained with Hematoxylin and Eosin, as well as Masson’s trichome stains (Suvarna et al., 2019).

The uteri were thoroughly inspected immediately after exsanguination and Swabs were collected from the lesions and put in buffered peptone water transport media. Samples were kept on ice bags and sent to the Microbiology laboratory of a College of Veterinary Medicine, King Faisal University. Identification of the bacteria was carried out as described previously by (Quinn et al., 1994).

The collected data from female buffaloes was recorded and analysed via SPSS 16.0 program (SPSS 16.0 for Windows Evaluation Version Release 16.0; 06 Septemper 2007). The chi-square test was in the evaluation of different variables. P < 0.001 was considered statistically for seasonal variations.

Uterine lesions were observed in 78 animals out of 340 (22.94%). Buffaloes were more susceptible to infection in summer comparable with spring, winter, autumn (Chi-square 70.44, P <0.001) (Table 1). In summer time, there are the suppression of ovarian activity and increasing embryonic deaths (Campanile et al., 2007; Ponraj et al., 2017).

The acute endometritis was noticed in 6/33 animals (18.18%) and five of them were positive for bacteriological examination. Grossly, the uterine mucosa was severely congested and oedematous. Histologically, the lining epithelium of the endometrium was eroded and the endometrial stroma was highly infiltrated by neutrophils (Figure 1A). The stromal blood vessels were greatly congested and few of them showed fibrin thrombi (Figure 1B). Ultrastructural examination revealed several vacuoles inside neutrophils containing electron-dense rod-like structures (Figure 1C). The presence of bacteriaindicates recent infection and early stage of inflammation (Table 2).

Table 1: Pathological lesions in the uteri of buffaloes during different seasons.

Table 2: Isolates of bacteria and its frequency in various types of inflammation of uteri.

This finding was coincided with Bhadaniya et al. (2019). Chronic endometritis was noticed in 27/33 animals (81.82%) and one case was positive for bacteriological examination. Grossly, the uterine mucosa was corrugated and appeared dirty yellow in colour. Histologically, the endometrial surface was completely necrosed and the endometrial stroma was highly infiltrated by lymphoplasmacytic infiltration. Periglandular fibrosis (2-5 layers) was noticed in most cases (Figure 1D). The major chronic inflammatory cells were Lymphocytic type and/or plasma cells. Gonzalez et al. (1985) explained that the presence of these cells indicates the local production of sperm antibodies which interfere with conception. The presence of these types of cells may cause infertility and failure of implantation (Mohyuddin et al., 2019). Periglandular fibrosis was also seen in most cases of chronic endometritis and this finding was agreed with Salemi et al. (2020) in water buffaloes in Iran. Messier et al. (1984) clarified that perigandular fibrosis plays an important role in the reduction of uterine milk, early embryonic death, and consequently repeat breeder. Metritis was observed in 5 animals (1.47%) and all cases seemed to be chronic. Similar findings were observed in buffaloes and could be attributed to retained placenta or dystocia (Kaneene and Miller, 1994; Parmar, 2018). Endometrial hyperplasia was recorded in 5 animals (1.47%). Similar finding was recorded by several authors (Saxena et al., 2006; Pereira et al., 2015). Cystic graafian follicles, ovarian neoplasms (granulosa cell tumors especially), and estrogens from plants are causes of endometrial hyperplasia in the cow (Zachary, 2017). Adenomyosis was observed in 2 animals (0.58%). There were clusters of endometrial glands growing throughout the muscular layer of the uterus (Figure 2A). Similar percentage was recorded in buffloes (Saxena et al., 2006). However, Alfaris and Fahid (2009) recorded a higher percentage (20%). Adenomyosis may arise as a malformation or due to hyperplastic overgrowth of the endometrium (Jubb et al., 1993). Adenomyosis could be the cause of anoestrum and repeated breeding in buffaloes (Alfaris and Fahid, 2009). Fibroma was observed in 3/340 animals (0.71%). There were bundles of collagen fibers running in different directions and mostly seen around blood vessels (Figure 2B). Perimetrial cysts were observed in 11 animals (3.24%). The cysts have thin walls containing a clear fluid and were firmly adhered to the outer uterine wall (Figure 2C). Similar cysts were recorded in buffaloes (Mittal et al., 2009). McEntee (1990) explained that cysts developed in postpartum uterine involution in which the myometrium contracted leading to the infolding of perimetrium. Perimetrial nodules were observed in 10 animals (2.38%). The nodules appeared as single or multiple have red or greyish colour, and are of different sizes and shapes (0.4 in diameter) (Figure 2D).These nodules could be indicative of chronic reaction due to continuous irritation during an examination of animals with reproductive problems.

The conclusion is that uterine disorders play a crucial role in female buffaloes infertility. It is highly recommended to use specific clinical parameters and biopsy techniques for early diagnosis in order to proceed with the appropriate treatment.

This work was supported through the Annual Funding Track by the Deanship of Scientific Research, Vice Presidency for Graduate Studies and Scientific Research, King FaisalUniversity, Saudi Arabia (Grant number 5301).

The present study tries to clarify that certain uterine disorders may play a major role in female buffalo infertility.

MH designed the study. AJ examined histopathology. FH interpreted the data. AA prepared the manuscript. MH critically revised the manuscript. All the authors approved the final version of manuscript.

The methods of the study were approved by the Research Ethics Committee at King Faisal University, Saudi Arabiba with Approval number KFU-REC-2022-NOV-ETHICS285.

The authors have declared no conflict of interest.