Preferential infection sites of Cysticercus bovis in cattle experimentally infected with Taenia saginata eggs.

The preferential sites of infection of Cysticercus bovis were evaluated in the skeletal muscle and entrails of 25 cattle that were experimentally infected with Taenia saginata (2×10(4) eggs). Two other animals were not inoculated (control). Ninety days after inoculation, all the cattle were euthanized. The carcasses were deboned and dissected into 26 anatomical sections (masseter muscles, brain, tongue, esophagus, heart, diaphragm, lungs, liver, kidneys, spleen, top sirloin butt, bottom sirloin butt, outside round, top (inside) round, transversus abdominus, top sirloin cap, strip loin, full tenderloin, eye of round, knuckle, shoulder clod, foreshank, shank, chuck, back ribs, and tail muscles). The dissected tissues were sliced into 5mm sections. From the 25 cattle, 9258 C. bovis (cysticerci) were recovered; 75.02% (6946) of these were recovered from skeletal muscles and 24.98% (2312) from the entrails. A high parasitism level was found in the shoulder clod (12.55%), heart (11.02%), liver (9.48%), masseter muscles (8.51%), chuck (8.25%), strip loin and full tenderloin (7.26%), knuckle (6.63%), and back ribs (5.53%), totaling 69.23% (5738) of all of the detected cysticerci. On the other hand, there was a low C. bovis parasitism level in the brain, spleen, tail muscles, kidneys, esophagus, and diaphragm, representing just 3.9% of the total number of cysticerci. Given these results, we conclude that specific skeletal musculature regions, such as the shoulder blade, chuck, strip loin and full tenderloin, knuckle, back ribs and top round, which are not officially examined in many countries, are effective sites to efficiently screen C. bovis infection. To date, these regions have not been considered as preferential sites of C. bovis infection. Based on our work, however, these regions deserve greater attention from health inspectors because they contained a greater number of Cysticercus than the other regions of carcasses that are parasitized by T. saginata larvae.

Detection of Toxoplasma gondii in the reproductive system of male goats / Detecção de Toxoplasma gondii no sistema reprodutor de caprinos machos

Male goats of mating age serologically negative for Toxoplasma gondii were divided into three groups: GI controls(placebo) (n = 2); GII infected with 1 × 10 potention 6 tachyzoites (RH strains) (n = 2); and GIII infected with 2 × 10 potention 5 oocysts(P strains) (n = 2). Clinical, hematology, parasite and serology tests and studies of parasites in the semen through bioassayand polymerase chain reaction (PCR), and in reproductive organs (bioassay) were performed to assess toxoplasmainfection. Serological titers peaked at 4096 in two animal groups infected with the protozoan. The bioassays allowed anearly detection of protozoa in semen samples of tachyzoite-inoculated animals. T. gondii DNA was identified throughPCR in the semen in five (Days 5, 7, 28, 49, and 70) and two (both at day 56) different days post-inoculation in GIIand GIII animals, respectively. It was also possible to detect T. gondii DNA in reproductive organs (prostate pool,testicles, seminal vesicle and epididymis) of goats inoculated with either tachyzoites or oocysts. The present studysuggests the possibility of venereal transmission of T. gondii among goats and it should be further assessed.(AU)

Caprinos machos, em idade reprodutiva, sorologicamente negativos para Toxoplasma gondii foram distribuídos emtrês grupos de animais: GI (n = 2) controle (placebo), GII (n = 2) - infectado com 1 × 10 elevado a 6 taquizoítos (cepa RH) e GIII(n = 2) infectado com 2 × 10 elevado a 5 oocistos (cepa P). Exames clínicos, hematológicos, parasitêmicos, sorológicos, pesquisano sêmen e em tecidos do sistema reprodutor, por meio da bioprova, e da Reação em Cadeia pela Polimerase (PCR),foram conduzidas para avaliar a infecção toxoplásmica. Os títulos sorológicos alcançaram valores máximos de 4096 nosdois grupos de animais infectados. Pela técnica da bioprova, foi possível revelar precocemente a presença do coccídionas amostras seminais dos animais inoculados com taquizoítos. Pela PCR, foi possível identificar, no sêmen, materialgenético de T. gondii, em cinco (5º, 7º, 28º, 49º e 70º) e em duas (ambos ao 56º) datas experimentais pós‑inoculaçãodos animais pertencentes aos grupos GII e GIII, respectivamente.Por esta mesma técnica, foi possível ainda isolarmaterial genético deste protozoário, também em amostras teciduais (pool de próstata, testículo, vesícula seminal eepidídimo) dos caprinos inoculados com taquizoítos e oocistos. A presente pesquisa sugere a possibilidade da ocorrência da transmissão sexual do T. gondii na espécie caprina.(AU)