Cystoisospora suis Control in Europe Is Not Always Effective

Abstract

After introduction of the anticoccidial toltrazuril for the metaphylactic treatment of suckling piglet coccidiosis, only few field evaluations on the effect of treatment against the causative agent, Cystoisospora suis, were performed. In 2018, a field study was conducted to detect the presence of the parasite on pig farms in four different European countries, and to evaluate management parameters possibly associated with infection and disease. A total of 49 farms from Austria, the Czech Republic, Germany and Spain were included. Repeated pooled fecal samples from 603 litters were taken in the 2nd and 3rd week of life. Samples were examined by autofluorescence for the presence of C. suis, and fecal consistency was scored. For each farm a questionnaire was provided to document management and treatment history. Feces scored as diarrhoeic were not significantly more often positive for C. suis than non-diarrhoeic feces but samples from litters with previously reported occurrence of diarrhea were significantly more often positive (p = 0.000). Pasty feces were significantly more often positive than those of other consistency (p = 0.005). Overall, 71.4% of the farms and 50.1% of the litters were positive for C. suis at least once. The prevalence on the farms reached up to 100%. Diarrhea was seen in samples from 53.1% of the farms (9.6% of the litters). Cystoisospora suis was diagnosed on 80.8% of the farms with vs. 60.8% of those without diarrhea. Toltrazuril was applied on 30 farms, and of these 53.3% had diarrhoeic samples and 66.7% were positive for C. suis vs. 19 farms that did not use toltrazuril with 52.6% diarrhoeic and 79.0% C. suis positive samples (p > 0.05). Only on two farms a disinfectant with activity against coccidia was used, and C. suis was not detected there. Current control of C. suis appears to be insufficient on the majority of the examined farms. These findings highlight the importance of correct application of medication, and an effective hygiene management. To maintain effective parasite control, efficacy monitoring of the control measures should be implemented.

Reduced treatment frequencies with bumped kinase inhibitor 1369 are effective against porcine cystoisosporosis

“…A single dose of 10 mg BKI 1369/kg BW was highly effective in reducing oocyst shedding and diarrhea, and improved body weight gain in infected piglets, therefore it can be considered as the minimal effective dose to control C. suis infections. It should be combined with thorough cleaning and disinfection to minimize the infection pressure ( Hinney et al, 2020 ; Joachim and Shrestha, 2020 ). Treatment of piglets at 3 days of life is recommended to receive best treatment efficacy, since BKI 1369 targets merozoites, not the invasive sporozoites, and should be applied after infection but before the onset of oocyst excretion and diarrhea for maximum efficacy.…”

“…The disease is generally non-fatal but shows high morbidity in affected litters ( Joachim and Shrestha, 2020 ; Lindsay et al, 1985 ). It has a wide prevalence ( Hinney et al, 2020 ; Joachim and Shrestha, 2020 ) thereby inducing substantial economic losses in the pig farming industry ( Kreiner et al, 2011 ; Mundt et al, 2007 ; Skampardonis et al, 2010 ). Current therapeutics for cystoisosporosis are limited to the triazinone toltrazuril ( Mehlhorn and Greif, 2016 ).…”

Suckling piglet coccidiosis on farms in the Czech Republic - A pilot study

“…None of the farms treated piglets with oral toltrazuril before the 3 rd day of life. The early treatment per os is correlated with the oocyst shedding (Hinney et al 2020); so, this may, in part, explain why the oocysts were still detected after the toltrazuril treatment. The use of a recently registered injectable formulation of toltrazuril in combination with gleptoferron for treatment during the first three days after birth was not recorded on the farms participating in the study.…”

“…Recently, an updated survey on the prevalence of C. suis in suckling piglets has been conducted in several European countries including the Czech Republic (Hinney et al 2020). Other parameters were added to the data originating from the Czech farms and used in a study, published by Hinney et al (2020), and assessed in order to provide a more detailed analysis.…”

Management practices related to the control of gastrointestinal parasites on Swedish pig farms

“…[19][20][21][22][23]. Resistance to toltrazuril has also been identified in C. suis, highlighting the necessity of responsible and more restrictive use of anticoccidial drugs [24,25].…”