The study was conducted to investigate chronic diarrhea cases and therapeutic trial in dairy cattle and buffaloes infected with Balantidium coli. Hundred and one adult dairy cattle and buffaloes presented with the history of diarrhea (>2 weeks) were selected for the study. Balantidium coli was isolated and diagnosed in 38 infected cattle and buffalo. Therapeutic efficacy of oral and intravenous metronidazole in dairy animals due to balantidiasis was evaluated. Efficacy of drug in the study was determined on the basis of reversal of clinical signs and reduction in Balantidium coli cysts/ trophozoites count. Complete clinical recovery was observed in 42.1 per cent of animals treated with oral metronidazole and in 63.1 per cent animals treated with intravenous metronidazole given at the dose rate of 10 mg/kg b.wt. The findings of this study substantiate that B. coli caused chronic diarrhea and haematological alterations of varied intensity in dairy cattle and buffaloes even with low cyst count and metronidazole as therapeutically effective drug, should be taken into consideration.
The causes and patho-physiologic features of chronic diarrhea in bovines still remains a mystery in most cases. Not much previous studies have been done on chronic diarrhea in cattle and buffalo. The identification of the specific cause is essential for rational treatment of clinical cases and in the prevention and control of the disease. Parasitic infections are other major constraints for profitable dairy industry associated with chronic diarrhea and loss of body condition in tropical and subtropical countries including India (Hassan and Juyal, 2006). Among the protozoan diseases, balantidiasis caused by Balantidium coli (a largest ciliate protozoan), is associated with chronic diarrhea in cattle (Alam et al., 1979) and water buffaloes (Islam et al., 2000; Randhawa et al., 2010). Balantidium coli has worldwide distribution in a variety of hosts, including both domestic and wild animals. The disease is endemic and prevalent worldwide, mostly prevalent in subtropical and tropical regions (Sampurna, 2007). Balantidium coli is a natural inhabitant of the caecum, colon and rectum of apparently healthy animals, produces clinical disease under certaincircumstances (Samad, 1996a). The clinical features are manifested by loose faeces to watery foetid diarrhea with dehydration, loss of appetite, retarded growth, loss of body condition and reduced production performance of the animals (Palanivel et al., 2005). In the chronic form, there are episodes of intermittent diarrhea, weight loss or muscular weakness (Ichhpujani and Bhatia, 1994). The disease may be diagnosed by direct demonstration of the parasite (trophozoites and cysts) from faeces, intestinal scrapings and in wet mounts of fresh faeces. Balantidium coli also produce hyaluronidase (Templis and Lipenko, 1957) which potentially enhances its ability to invade the intestinal mucosa. Nitro heterocyclic compounds can be used as therapeutic agents in the treatment of balantidiasis (Raether and Hanel, 2003). The therapeutic efficacies of various drugs like Secnidazole, Metronidazole, Benznidazole and Furazolidone have been documented against Balantidium coli. Metronidazole is also successful in some cases against balantidiasis in livestock (Reddy and Reddy, 1993; Patil et al., 1998). The efficacy of drugs is mainly determined on the basis of disappearance of clinical signs and reduction of cysts/trophozoites in faeces. The purpose of this study is to describe the clinical and therapeutic findings of cattle and buffaloes naturally infected only by Balantidium coli, in view of the paucity of such information about this disease in dairy animals.
Materials and Methods
The study involved 101 chronic diarrhea cases of cattle and buffalo of different age and breeds presented at large animal clinics of Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana. Tentative diagnosis of chronic diarrhea was made on the basis of history and clinical examination. Detailed history was recorded with respect to age and species; duration of diarrhea; number of animals affected; dietary history; body condition; course of diarrhea-recurrent/persistent frequency of diarrhea; other clinical signs associated with diarrhea; and faecal abnormalities were recorded and a clinical examination was carried out to determine the severity and nature of diarrhea. For body condition scoring (BCS) numerical value between 1 and 5, was given in order to gauge overall condition of body in terms of size of the affected animal. Each animal was subjected to general physical examination and rectal examination for lymphadenopathies. Rectal examination included- intestinal status and any abnormal masses. Each animal was thoroughly evaluated for its general condition (alert or depressed), status of diarrhea (persistent or intermittent) and weight loss (gradual or severe). The vital parameters recorded were rectal temperature (°F), heart rate, respiration rate and colour of mucous membrane. Auscultation of heart was performed to detect any abnormality.
Blood samples were collected from juglar vein puncture. Faecal samples and rectal scrapings were collected directly from the rectum of the animal. The sedimentation and direct wet smear methods were used to find the parasitic eggs and B. coli cysts. All the faecal smears from diarrheic animals were also screened for bacilli, squamous epithelial cells and cell debris, undigested plant fibre(s).
Prevalence of B. coli was estimated by Pearson’s chi-square test for significance whereas data on hematology was analyzed by Student’s t-test. P<0.05 was considered as significant.
Results and Discussion
From the total of 101 clinical cases of dairy cattle and buffaloes, suffering from chronic diarrhea, Balantidium coli was isolated and diagnosed from 37.9 per cent (n=38) of adult dairy cattle and buffalo. Balantidium coli infection was seen in 39.3 per cent (n=26) of cattle and 34.2 per cent (n=12) of buffaloes. Feeding pattern in 62.7 per cent (n=64) of animals was normal where as 35.6 per cent (n=36) of animals had reduced feeding pattern (Table 1).
Table 1: Level of Balantidium coli infection in diarrheic and non-diarrheic cattle and buffalo
|No. of Cases
|No. of Cases
|Total No. of animals
|Mean Cyst Count
|Per cent Affected
No change in body weight was observed in 68.4 per cent of animals whereas partial weight loss was observed in 18.4 per cent of animals. On clinical examination twenty one animals (55.2%) had average body condition score (3-3.5) whereas 17 animals (42.2%) animals had poor body condition score (2-2.5). Watery faeces were recorded from 47.3 per cent animals, 34.2 per cent animals had moderately loose faeces and 18.42 per cent of cattle and buffaloes had mildly loose (soft feces). Foul smelling faeces were reported in 5 animals (13.1%) whereas 33 animals (86.8%) had normal faecal odor. The vital signs (temperature and heart rate) of 38 animals were within normal range.
In the present study, 32.3 per cent positive cases revealed cysts while 5 per cent (n=4) positive cases revealed both cysts and trophozoites (Fig.1).
Fig 1: Level of Balantidium coli infection in diarrheic and non-diarrheic cattle and buffalo
The mean of cyst count 2.73±0.918 hpf was recorded in balantidiasis affected animals. Severity of diarrhea was less in animals with faecal cyst count 2-3 high power field, whereas it was moderate with cyst count 3-5 high power field and severe with cyst count above 5 high power field. Non-diarrheic animals revealed only cysts and the mean cyst count was 0.11±0.447 hpf and only five per cent were positive for rare Balantidium coli. In both, cattle and buffaloes having normal faecal consistency (control group), only cysts were revealed in all positive cases whereas trophozoite was not observed in faeces of any of the animal. Chronic balantidiasis is characterized by the signs of alternating watery diarrhea of prolonged duration (Ichhpujani and Bhatia, 1994). Diarrheic loose faeces and moderate loss of body weight in cattle with B. coli infection was reported by Sudan et al. (2012). Diarrhea due to Balantidium coli infection was also reported by Patnaik (1965), Christopher and Rao (1972), Singh (1979), and Sahoo et al. (1984).
Level of infection with respect to severity of diarrhea was determined on the basis of cyst count. The incidence of Balantidiasis was higher in cattle and buffalo with chronic diarrhea as compared to bovines having normal faecal consistency. This finding was similar in cattle and buffaloes. Sengar and Singh (2005) reported that 51.9 per cent of positive cases revealed only cysts, while 48.03 per cent positive cases revealed both cysts and trophozoites in cattle. The diarrhea associated with presence of both trophozoites and cysts was observed by Sreemannarayana et al. (1976). The paucity on the reports on the occurrence of trophozoites of Balantidium coli in bovines may be due to their quick disintegration in faecal sample. Sengar and Singh (2005) reported similar results with higher incidence of B. coli infection in bovines having diarrheic faecal consistency as compared to bovines having normal faecal consistency. Udupa et al. (1998) reported Balantidium coli prevalence rate 17.07 per cent in buffaloes with the history of diarrhea. Motaleb (1996) reported prevalence rate of balantidiasis as 1.5 per cent and 2.2 per cent in dairy cattle and buffalo’s respectively in Bangladesh whereas Sahoo et al. (1984) reported 1.2 per cent prevalence rate in cattle and buffaloes in India. Palanivel et al. (2005) reported higher prevalence of Balantidium coli as 45.4 per cent and 51.4 per cent in cattle and buffaloes, respectively, which is higher than the findings of the present study. The variations between the present and previous findings might be due to difference in the disease condition, geographical location, climatic condition, and managemental factors of the animals. Islam et al. (1988) and Rajkovic et al. (1997) observed that the prevalence of the balantidiasis in dairy animals valued from 12-48 per cent in Bangladesh and Croatia respectively. Islam et al. (2000) reported the higher prevalence of Balantidium coli infection in adult buffaloes of 5 years age (4.0%) than in animals below 2 years (3.4%). Since Balantidium coli infection was recorded more in diarrheic cases, it could be suggested that Balantidium coli infection causes chronic diarrhea. Balantidium coli has two developmental stages, a trophozoite stage and a cyst stage and usually affects the large intestine, from the caecum to rectum. The trophozoite is motile and contains cilia around its ovoid shaped body. Diagnosis of balantidiasis is established by demonstration of cysts or trophozoites of Balantidium coli in faeces (Samad, 1996b). Balantidia produce no known toxins, but their ability to produce ulceration of the colon wall is attributed to hyaluronidase, an enzyme that digests hyaluronic acid, which potentially enhances its ability to invade the intestinal mucosa, and cause enteritis.
Therapeutic Study in Balantidium coli Treated Group
Efficacy of drugs used in the study was determined on the basis of clinical response. The effect of metronidazole treatment is presented in Fig.2 and Table 2.
Table 2: Effect of metronidazole on cyst count of Balantidium coli infected dairy cattle and buffaloes
|Oral treatment group (n=19)
|I/V treatment group (n=17)
Significant (P<0.01) difference between groups at pre treatment and post treatment
Mean cyst count reduced from 2.41±1.16 to 0.11±.33 hpf with oral metronidazole treatment. Similarly mean cyst count decreased from 2.73±0.91 to 0.18±0.44 hpf with intravenous metronidazole treatment. Complete clinical recovery was observed in 42.1 per cent of animals and 31.5 per cent animals showed no clinical recovery treated with oral metronidazole (Table 3). Treatment with intravenous infusion of metronidazole, resulted in recovery in 63.1 per cent of cases and 17.6 per cent did not recovered.
Fig 2: B. coli cyst count in oral and I/V pre and post treatment groups
Table 3: Clinical response to metronidazole therapy in Balantidium coli induced diarrhea
|Oral Metronidazole (n=19)
|Intravenous Metronidazole (n= 17)
The relapse of diarrhea occurred in 26.3 per cent of animals treated with oral metronidazole and 11.7 per cent of animals had clinical relapse treated with intravenous therapy. The clinical response was achieved over a period of 7-10 days of the initiation of treatment. Successful treatment of bovine balantidiosis with metronidazole has been reported by some authors (Reddy and Reddy, 1993; Patil et al., 1998). Recovery rate was 63.1 per cent against bovine balantidiasis, similar (68% recovery) to the findings of Christopher and Sudharshana (1972) in cattle and buffaloes. Rehman and Samad (2010) reported that a single oral dose of metranidazole resulted in reduction of Balantidium coli trophozoites by 42.8 per cent. When given intravenously or orally at usual recommended doses, metronidazole attains concentrations well above the minimum inhibitory concentrations for most susceptible micro-organisms. Present findings are in line with Raether and Hanel (2003) who reported that nitro heterocyclic compounds (Secnidazole, Metronidazole, Benznidazole and Furazolidone) can be used as treatment drugs against balantidiasis.
Animals with diarrhea had significantly (P<0.05) higher mean cyst count (38%; chi square=30.34, p=0.0001) in comparison to non-diarrheic cattle and buffalo (5%).
Balantidiasis was higher in bovines with chronic diarrhea as compared to bovines having normal faecal consistency. B. coli infected cattle and buffalo revealed cysts in 32.3 per cent cases while 5 per cent positive cases revealed both cysts and trophozoites. Mean of cyst count was 2.73±0.91 in diarrheic animals and 0.11±0.44 in non-diarrheic animals. Efficacy of drugs used in the study was determined on the basis of reversal of clinical signs and reduction in Balantidium coli cysts/ trophozoites count. Complete clinical recovery was observed in 42.1 per cent of animals and 31.57 per cent animals showed no clinical recovery treated with oral metronidazole.
The author acknowledges Department of Science and Technology (DST), Government of India for providing necessary support under AORC INSPIRE programme.