Neospora caninum, Sarcocystis spp. and Toxoplasma gondii infections and their relationship with milk production in goats from Argentina

STEFFEN, K.D.; GOS, M. L.; ARIAS, R.O.; MORÉ, G.

Encuentro; 6th International Meeting on Apicomplexan Parasites in Farm Animals (Apicowplexa 2022); 2022

"Goats are intermediate hosts of Neospora caninum, Sarcocystis spp. and Toxoplasma gondii. Neosporosis and toxoplasmosis in goats have been extensively studied in different regions of the world related to reproductive losses. Sarcocystis spp. infection is generally asymptomatic and rarely cause clinical signs and abortions. In general, goat seroprevalence of these infections is high, although the impact on milk production is unknown. The aim of this study was to evaluate and relate the antibodies titers to these protozoa with the goat milk production in the province of Buenos Aires, Argentina. Blood samples were obtained from 336 Saanen breed goats from 2 dairy farms: E1 (N=146) and E2 (N=190). Sera were tested for N. caninum, Sarcocystis spp. and T. gondii antibodies by indirect immunofluorescence antibody test (IFAT) and processed to end dilution. In both dairy farms, milk production volume was measured once a month from August to December. The total production per lactation was calculated and adjusted to 240 lactation days. Differences in antibody titers were explored considering age, body condition and FAMACHA© grade as covariates using a multifactorial ANOVA test. The average total milk production of goats by lactation was 429.3 l (IC±17.8). The seroprevalence of N. caninum, Sarcocystis spp. and T. gondii was 81.8% (275/336), 96.4% (324/336) and 66.7% (224/336), respectively. Fifty-four percent (181/336) of goats were seropositive to three protozoa, 37.5% (126/336) to two and 8.3% (28/336) to only one. No significant differences in milk production were found between seropositive goats to three and two protozoa and positives to one or negatives to all three. Neospora caninum seropositive goats at cutoff titers ≥200 and ≥400 showed significantly higher milk production than the rest. Similarly, Sarcocystis spp. seropositive goats with cutoff titers ≥200 and ≥400 evidenced higher milk production than seronegative and lower titer goats. On the other hand, seropositivity to T. gondii at different titer cutoff levels showed no association with differences in milk production, except for 16 goats with titers ≧1600 which produced significantly less milk than the rest. Results confirm that N. caninum, Sarcocystis spp., and T. gondii infections and coinfection are common in dairy goats from the province of Buenos Aires, Argentina. High seropositivity at the three protozoa may determine a significant economic impact because of the reproductive failures. However, and contrary to our hypothesis, seropositivity was not related with lower milk production and even the seropositive animals with higher titers produced more than seronegative and low titers goats. Possibly, the high seropositivity observed influences the statistics, since seronegative goats are underrepresented. The animal's age, body condition and anemia degree (FAMACHA©) are important factors determining milk production in goats, and therefore, should be considered as in our study toavoid misinterpretations."