Epidemiological aspects of canine babesiosis in the semiarid area of the state of Minas Gerais, Brazil

Epidemiological aspects of Babesia vogeli infection were studied in the canine population of a rural town located in the Brazilian “Drought Polygon” of the state of Minas Gerais, Brazil. The survey was carried out in March 2003, when 505 dogs were identified and their characteristics registered on appropriate forms. Blood samples were collected at this time and again in June, September and December 2003. Serum samples were tested by the indirect fluorescent antibody test (IFAT) to detect antibodies against B. vogeli. The prevalence of anti-B. vogeli antibodies was 18.8%; however, no correlations were found between prevalence of infection and the age or gender of the animals. Cross-bred dogs presented a higher chance of acquiring infection in comparison to pure-bred dogs. Significant differences concerning the incidence of the disease were found during the period April–June in comparison to other months, demonstrating that transmission of B. vogeli is related to seasonal variations of tick infestations. The results indicate that climatic factors within the semiarid area interfere directly in the epidemiology of canine babesiosis.     

Implications of carbohydrate sources and rate of body weight gain on puberty in ewe lambs in tropical climate conditions

Tropical Animal Health and Production - The objectives were to evaluate the effects of two non-fibrous carbohydrate sources and the rate of body weight gain on puberty status in ewe lambs. Sixty...     

Effect of age of donor on embryo production in Morada Nova (white variety) ewes participating in a conservation programme in Brazil

In order to evaluate embryo production in Morada Nova (white variety) ewes superovulated with porcine follicle-stimulating hormone, 20 cycling ewes were used as embryo donors and allocated into two groups according to age: group 1 (ewes aged 1–2 years; n = 9) or group 2 (ewes aged 3–4 years; n = 11). Embryo recovery was performed by laparotomy 5–6 days after oestrus. The evaluation of embryos was made under stereomicroscope according to International Embryo Transfer Society rules. The overall recovery rate was 64.6% (5.0 ±  0.7 structures per ewe) and 86.3% of the recovered structures were fertilized. Group 1 was superior (p < 0.05) to group 2 according to recovered (6.6 ±  0.9 vs 3.6 ±  0.8) and fertilized structures (5.6 ±  1.1 vs. 3.5 ±  0.7) per ewe. In conclusion, the ovarian response and the embryo production in Morada Nova (white variety) sheep subjected to a standard superovulation treatment were considered satisfactory. In addition, the use of multiple ovulation and embryo transfer in younger ewes (≤ 2 years old) of this sheep breed appears to be an efficient tool to accelerate the preservation of the Morada Nova (white variety) breed, since younger ewes are as responsive as older ones.     

Bagaza virus is pathogenic and transmitted by direct contact in experimentally infected partridges,but is not infectious in house sparrows and adult mice

Bagaza virus (BAGV) is a mosquito-borne flavivirus belonging to the Ntaya serocomplex. In 2010, a disease outbreak was reported in Cádiz (Southern Spain) affecting game birds (red-legged partridges and common pheasants). In this work, red-legged partridges were inoculated experimentally with infectious BAGV isolated from this outbreak in order to make a complete clinical and analytical assessment of the disease caused by the pathogen in this species. Viral load (by real-time RT-PCR) in blood, oral and cloacal swabs, and feathers, and neutralizing antibody titres (by VNT) were measured. In order to determine direct contact transmission, non-inoculated partridges were caged together with the inoculated ones. To assess infectiousness in other species, house sparrows and mice were also inoculated with the virus. All the inoculated partridges were clinically affected, and 30% of them died. All the infected individuals lost weight, with larger losses being recorded in females. Conversely, no mortality or disease symptoms were observed in the sparrows or mice. Remarkably, all the contact partridges acquired the infection by direct (non-vectored) transmission. This study confirms that the red-legged partridge is a susceptible host for BAGV infection, and that this pathogen is transmitted by direct contact. Long-lasting viral loads detected in calami of immature feathers demonstrate that feather sampling could be a useful strategy in active surveillance programs for early detection of BAGV.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0233-9) contains supplementary material, which is available to authorized users.