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This case report describes a concomitant infection in a litter of puppies with two apicomplexan protozoa Neospora caninum and Hepatazoon canis. The different potential routes of infection are discussed along with a description of the course of the disease. A private practitioner in the South of Israel (Beer Sheva) submitted blood samples for serological testing for toxoplasmosis and neosporosis from a pup of 6 weeks of age (from a liter of 6 pups) showing neurological symptoms. The results were seropostive for N. caninum and seronegative for toxoplasmosis. After 3 weeks another pup also started to develop neurological signs. Samples including blood smears, serum samples for serology for Neospora and Toxoplasma and fecal samples from all the pups. Out of the 6 pups tested four were found seropositive for Neospora while all pups were seronegative for Toxoplasma. Of the six pups, four were found to be infected with Heptaozoon canis, three of which were coinfected with N. caninum. One pup was infected with only H. canis and another pup with only N. caninum and a third pup was found to be negative for both H. canis and N. caninum. Treatment consisted of trimethoprim sulfadiazine and clindamycin which were administered for six weeks. The pups recovered completely, with the exception of paresis of the left hind limb in the first diagnosed puppy. An important conclusion from this case report is the need to test all pups in a litter for N. caninum where even only one pup shows clinical signs. Furthermore treatment at an early age and for a prolonged period of time appeared to be successful in preventing the progression of the clinical signs. To the best knowledge of the authors this is the first natural concomitant infection case of N. caninum and H. canis in a litter of puppies. [ABSTRACT FROM AUTHOR]

Neosporosis, caused by infection with the intracellular protozoan Neospora caninum, is recognized as one of the major causes of infectious abortion in cattle. Since abortion is the only clinical sign associated with N. caninum infection, diagnosis is complicated, however it is crucial to understand the epidemiology of the disease, and to undertake measures to reduce losses to the cattle industry. In Israel the diagnosis of neosporosis is based on the detection of specific antibodies in aborted dams, or in the body fluids of aborted fetuses. The presence of antibodies in sera of aborted dams indicates exposure to N. caninum, but does not necessarily point to the causative agent of the abortion. In the present study sera from 7,951 aborted dams and body fluids from 446 fetuses were analyzed by the indirect fluorescent antibodies test (IFAT ). N. caninum seropositivity was found in 51.4% of the dams, and in 18.2% of the fetuses. In addition, primers were designed for the detection of N. caninum DNA, by a specific nested PCR (nPCR) test, in brain tissues from aborted fetuses. The primers do not react with other closely related apicomplexa species. The performance of both molecular and serological assays was evaluated in 97 samples of fetuses. Comparable results were observed in 57 negative and 20 positive samples, while 20 remaining samples showed positivity in only one of the assays. In addition, 26 paired dam and aborted fetuses were tested. Of these, 15 samples obtained from dams or fetuses were found to be negative by both tests, 5 seropositive dams had positive fetuses in at least one of the assays, and 6 samples from seronegative dams were found to be positive in at least one of the fetus' assays. The results obtained show high prevalence of N. caninum in cattle in Israel and emphasize the necessity for the application of several methods for a reliable diagnosis of neosporosis as a cause of abortion. [ABSTRACT FROM AUTHOR]

Outbreaks of arthropod-borne (arbo) viruses that infect livestock impact the health and welfare of domestic and wild animals are often responsible for significant economic losses in livestock production. Surveillance and early warning systems effectively predict the emergence and re-emergence of arboviral disease. This paper presents the interim results of five years monitoring the exposure of sentinel naïve heifers and Culicoides biting midges (Diptera; Ceratopogonidae) to bovine ephemeral fever virus (BEFV), Simbu serogroup viruses, bluetongue viruses (BTV), and epizootic hemorrhagic disease viruses (EHDV). The data were collected from 11 dairy farms situated within eight different geographical regions in Israel. The results indicate that cattle in Israel are affected by all four viruses from the early summer onward. The investigated viruses exhibit unique site-specific profiles in both ruminants and vectors. The potential of several vectors to transmit these viruses and lack of cross-protection to re-infection with multiple serotypes (BTV and EHDV) or species (Simbu serogroup viruses) highlights some likely mechanisms that may play a role in these viruses' maintenance cycle and possible endemization in our region.

In this report, the transmission efficacy of Babesia ovis, the principal causative agent of ovine babesiosis, was studied by infestation of lambs with different Rhipicephalus bursa stages or by injection of infected blood. Infected blood injection induced acute babesiosis in splenectomized lambs, while only mild clinical signs were observed in intact animals. Both splenectomized and intact lambs developed high antibody titer, detectable for at least 180 days post infection. Infestation of splenectomized and intact lambs with infected tick larvae did not induce clinical babesiosis or specific serum response in any of the examined animals. Similarly, infestation of one splenectomized lamb with partially-fed infected R. bursa males did not induce any clinical response or seroconversion. Nymph infestation caused a mild clinical response followed by specific seroconversion, in one out of five lambs. All animals infested with infected unfed adults (males and females) showed mild-to-severe clinical signs 8 to 12 days post infestation. The acute phase was followed by a marked seroconversion. Our results indicate that the principal transmission of B. ovis is performed by adult R. bursa ticks, and that the host reaction can last as long as 6 months following the acute infection., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

The gene encoding Babesia ovis surface protein D (BoSPD) was cloned from B. ovis cDNA library. This gene encodes a polypeptide chain of 155 amino acids, including a predicted 22 amino acid signal peptide. Sequence analysis of the BoSPD suggested that it is a surface protein with no known domains. BLAST analysis followed by multiple alignments showed four orthologs from other Apicomplexan species and suggested that BoSPD is specific for B. ovis. BoSPD-based PCR was then developed to specifically detect B. ovis in experimentally-infected sheep and Rhipicephalus bursa ticks, as well as in field samples. The PCR enabled detection of B. ovis at a calculated parasitemia of 0.0016% and was shown to be specific for B. ovis. Moreover, the BoSPD PCR allowed detection of prolonged subclinical infection in experimentally-infected lambs and in dissected organs of experimentally-infected ticks. Finally, the PCR was used to detect parasitemia in blood samples from naturally-infected sheep and in R. bursa ticks collected from sheep in an infected flock. These results suggest that the BoSPD gene sequence can be used as a specific and sensitive marker, allowing detection of subclinical parasitemia in sheep and in ticks. Based on its predicted properties, BoSPD may be considered as a candidate for anti-B. ovis vaccine development or a target for anti-B.ovis treatment., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Neosporosis caused by caused by the apicomplexan parasite Neospora caninum is one of the major causes of infectious abortion in bovines worldwide. A long-term prospective study was performed in a dairy herd endemic for N. caninum in order to analyze the impact of neosporosis on the proportion of aborting cows. A total of 1078 pregnant cows were tested for presence of antibodies and the proportion of abortions was calculated. The overall seroprevalence of N. caninum found in the herd was 35.5%. The percentage of abortions in seropositive cows was 3 times higher than in their seronegative counterparts (21.6 and 7.3%, respectively). No statistically significant association was found between the antibody level of positive during pregnancy and the proportion of aborting cows. However, 41.2% of the dams with antibody titers of 1:12,800 aborted. The risk of abortion for such dams was 2.7 times higher than for other seropositive cows which had lower titers of antibodies (p=0.0072). In the follow-up examinations of the seropositive cows during several pregnancies, the overall percent of abortions observed was significantly higher than in seronegative individuals (49.3 and 16.9%, respectively; p<0.0001). Moreover, the proportion of repetitive abortion observed was 5 to 1 (17.4 and 3.5%) in seropositive and seronegative dams, respectively (p<0.001). The rate of vertical transmission in positive dams was 61.0% and it appeared to be directly associated with antibody levels: the higher the titer in the dams during pregnancy, the higher the percentage of sero-positivity in their calves. Increased proportion of abortions was observed in seropositive cows both in summer and winter in comparison with spring and autumn. It was found that in seropositive cows, an increased number of pregnancies, which was directly related to the age of the dam, has been associated with an increased number of abortions., (Copyright © 2014 Elsevier B.V. All rights reserved.)