Variables Associated with Infections of Cattle byBrucella abortus.,Leptospira spp. andNeospora spp. in Amazon Region in Brazil

Abstract

The frequency of Neospora spp., Leptospira spp. and Brucella abortus infections in adult cattle was determined in herds of the State of Pará, Brazil, which is an important region for cattle production located in the Amazon region. A total of 3466 adult female cattle from 176 herds were tested, leading to a frequency of seropositive animals of 14.7%, 3.7% and 65.5% and a herd positivity of 87.4%, 41.3% and 98.8% for infections caused by Neospora spp., B. abortus and Leptospira spp., respectively. The five most frequently diagnosed serologic responses to Leptospira spp. were those against serovars hardjo, wolfii, grippotyphosa, hebdomadis and shermani. The following associations were found: practice of artificial insemination, large farm size, large herd size, large number of dogs and high number of total abortions per year with the presence of antibodies against serovar hardjo; positive results to serovar grippotyphosa with the presence of dogs; inappropriate disposal of aborted foetuses with positivity to serovar hebdomadis. Serovar grippotyphosa was also associated with number of episodes of abortions. Neospora spp. positive herds were associated with episodes of abortion and B. abortus infection with the disposal of dead animals and aborted foetuses on pastures and with the use of artificial insemination. In conclusion, the high frequency of brucellosis, leptospirosis and neosporosis in the region may be a consequence of social, natural and raising conditions as: (i) climate conditions that favour the survival and spread of pathogens in the environment; (ii) farms located in regions bordering forest areas; (iii) farms in areas of difficult access to the veterinary service; (iv) extensive beef herds raised at pastures with different age and productive groups inter-mingled; and (v) minimal concerns regarding hygiene practices and disease prevention measures.

Bayesian evaluation of three serological tests for the diagnosis of bovine brucellosis in Bangladesh

“…There might be several reasons, including larger herd size, irregularly/not testing cattle, high proportion of cross-breed cattle, recent cattle introductions without proper testing and the sole use of AI at the GF. AI using semen from brucellosis infected bulls can spread disease [6, 52].…”

Ocorrência e fatores de risco da infecção pelo vírus da língua azul em bovinos no Estado de Pernambuco

“…A inseminação artificial já foi identificada em outros estudos como fator de risco associados a outras infecções (Almeida et al 2013, Chiebao et al 2015. Estudos indicam a presença e virulência do agente em amostras de sêmen, sendo necessária a certificação negativa para sua comercialização (Vanbinst et al 2010).…”

Investigating the Immunological and Biological Equilibrium of Reservoir Hosts and Pathogenic Leptospira: Balancing the Solution to an Acute Problem?

“…SP (Felt et al, 2011;Boey et al, 2019) SP (Campos et al, 2017) A (Chiebao et al, 2015;Loureiro and Lilenbaum, 2020) SP (Simbizi et al, 2016) SP (Lee et al, 2017) A (Greenlee et al, 2004) SP (Goldstein et al, 2006) A (Srinivas et al, 2013) Icterohae morrhagiae…”