The chronicity of Brucella abortus infection in humans and animals depends on the organism's ability to escape host defenses by gaining entry and surviving inside the macrophage. Although no human vaccine exists for Brucella, vaccine development in other bacteria has been based on deletions of selective nutritional as well as regulatory systems. Our goal is to develop a vaccine for Brucella. To further this aim, we have used a green fluorescent protein (GFP) reporter system to identify constitutively and intracellularly induced B. abortus genes. Constitutively producing gfp clones exhibited sequence homology with genes associated with protein synthesis and metabolism (initiation factor-1 and tRNA ribotransferase) and detoxification (organic hydroperoxidase resistance). Of greater interest, clones negative for constitutively produced gfp in agar were examined by fluorescence microscopy to detect promoter activity induced within macrophages 4 and 24 h following infection. Bacterial genes activated in macrophages 4 h postinfection appear to be involved in adapting to intracellular environmental conditions. Included in this group were genes for detoxification (lactoglyglutathione lyase gene), repair (formamidopyrimidine-DNA glycosylase gene), osmotic protection (K ؉ transport gene), and site-specific recombination (xerD gene). A gene involved in metabolism and biosynthesis (deoxyxylulose 5 phosphate synthase gene) was also identified. Genes activated 24 h following infection were biosynthesis-and metabolism-associated genes (iron binding protein and rhizopine catabolism). Identification of B. abortus genes that are activated following macrophage invasion provides insight into Brucella pathogenesis and thus is valuable in vaccine design utilizing selective targeted deletions of newly identified Brucella genes.Brucella spp. are gram-negative facultative intracellular bacteria and the causative agent of human and animal brucellosis, a persistent disease that is difficult to diagnose and treat. The bacteria penetrate the mucosa of the nasal, oral, or pharyngeal cavities and are phagocytized by host macrophages, where survival and replication occurs. Following a variable bacteremic stage, the organisms localize in the reticuloendothelial system. This intracellular localization likely accounts for the persistence of Brucella infections. Thus, the identification of bacterial proteins that contribute to the replication and survival of the bacteria is critical in understanding the protective mechanisms and pathogenesis of the disease.Although several virulence factors are known, the basis for virulence in Brucella infections remains poorly understood. Early studies on virulence factors were directed at the structural features of the outer membrane (37). The outer membrane contains two recognized virulence factors: lipopolysaccharide (LPS) and outer membrane proteins. LPS was recognized for its virulence role when naturally occurring isolates lacking LPS showed reduced survival. However, the role of outer membrane proteins in...

There is a constant expectation for fast improvement of livestock production and human health care products. The advent of DNA recombinant technology and the possibility of gene transfer between organisms of distinct species, or even distinct phylogenic kingdoms, has opened a wide range of possibilities. Nowadays we can produce human insulin in bacteria or human coagulation factors in cattle milk. The recent advances in gene transfer, animal cloning, and assisted reproductive techniques have partly fulfilled the expectation in the field of livestock transgenesis. This paper reviews the recent advances and applications of transgenesis in livestock and their derivative products. At first, the state of art and the techniques that enhance the efficiency of livestock transgenesis are presented. The consequent reduction in the cost and time necessary to reach a final product has enabled the multiplication of transgenic prototypes around the world. We also analyze here some emerging applications of livestock transgenesis in the field of pharmacology, meat and dairy industry, xenotransplantation, and human disease modeling. Finally, some bioethical and commercial concerns raised by the transgenesis applications are discussed.

ResumoSoros de 521 vacas do município de Avaré, SP, foram analisados pelos métodos de reação de imunofluorescência indireta (RIFI) e teste imunoenzimático (ELISA) para a detecção de anticorpos contra Neospora caninum. As amostras reagentes para Neospora também foram submetidas à RIFI para Toxoplasma gondii. Pelo método de RIFI 15,9% das amostras foram positivas para N. caninum nas diluições de 1:200 a 1:1600 e pelo teste de ELISA 30,5% dos soros foram positivos. Das amostras positivas para ELISA e negativas para a RIFI 1:200, 46 foram reagentes na diluição de 1:160. Todas as 129 vacas positivas para RIFI nas diluições ≥ 1:160 também o foram para ELISA. Dos 44 abortamentos constatados, 14 (31,8%) e 18 (40,9%) vacas apresentaram título na RIFI ≥ 1:200 e ≥ 1:160, respectivamente, e 24 (54,5%) reagiram ao teste de ELISA. Dos 159 soros que reagiram para N. caninum nos testes de RIFI e/ou ELISA, apenas seis foram positivos para T. gondii pelo método de RIFI e, das 44 vacas com histórico de abortamentos, apenas uma apresentou anticorpos anti-Toxoplasma. Esses resultados sugerem a presença de N. caninum nos rebanhos estudados e sua relação com os abortamentos observados. Palavras-chave: Neosporose, bovinos, Apicomplexa. AbstractSera of 521 dairy cows from herds in Avaré County, SP were examined by indirect fluorescent-antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to Neospora caninum. The positive samples for Neospora were also tested for Toxoplasma gondii by IFAT. By using IFAT 15.9% of the samples reacted for N. caninum with dilution between 1:200 and 1: 1600. By using ELISA 30.5% were seropositive for Neospora. Of the samples that were positive to ELISA and negative to IFAT for antibodies titers of 1:200, 46 showed IFAT titers of 1:160. All 129 cows that were seropositive to IFAT with titers of 1:200 and 1:160 were also positive to ELISA. Out of 44 detected abortions, 14 (31.8%) and 18 (40.9%) cows had IFAT titers of ≥ 1:200 and ≥ 1:160, respectively, and 24 (54.5%) cows were positive to ELISA. Of the 159 seropositive samples to N. caninum to IFAT and/or ELISA, only six were positive to IFAT to T. gondii. Moreover, among the 44 cows with history of abortion, only one demonstrated antibodies to Toxoplasma. These results suggest the presence of N. caninum in the herds that were evaluated and the potential relationship with the observed abortions.

Rickettsia spp. bacteria are responsible for tick-borne diseases worldwide, mostly maintained by rickettsial amplifiers capybaras in Brazilian endemic areas. The campus of the University of São Paulo, in southeastern Brazil, is an area endemic for Brazilian spotted fever (BSF), with high density of capybaras and Amblyomma spp., along with confirmed human cases. Besides capybaras, the university has also an in-campus high population of sheltered and free-roaming cats. Accordingly, the aim of this study was to determine the prevalence and characteristics associated with Rickettsia rickettsii, Rickettsia parkeri and Rickettsia felis exposure among cats in a BSF-endemic area. Out of 51 cats sampled, 23/35 shelter (65.7%) and 5/16 free-roaming (31.2%) were positive (titers ≥ 64) for at least one Rickettsia species. Ticks species were present in 3/16 free-roaming cats (18.8%), consisting of Amblyomma spp., nymphs of Amblyomma sculptum and adult Rhipicephalus sanguineus sensu lato. Despite sharing the capybaras environment, the seropositivity among the free-roaming and shelter cats was lower than owned cats in other endemic areas. Whether equally or less exposed to rickettsial infection, compared with owned cats in endemic areas, free-roaming and shelter cats may be used as environmental sentinels for human exposure to rickettsiae in such areas.

Sequelae due to testicular biopsy such as hemorrhage, adhesion and fibrosis may be limiting factors to the use of this surgical procedure. Fibrin glue (FG) derived from snake venom was used to minimize these sequelae, as well as to evaluate its healing property in tunica vaginalis and scrotal skin of rams. Applicability of fibrin glue derived from snake venom was tested in different tissues of other animals such as in sciatic nerve and colon of rats and skin of rabbits. In the present study, 30 healthy adult rams were used. They were divided into 3 groups of 10 animals each as follows: G1: fibrin glue group (application of fibrin glue on puncture sites and skin incisions after bilateral testicular biopsy with a Tru-Cut needle); G2: swab/nylon group (hemostasis by compression with a swab on puncture sites and skin suturing with nylon after biopsy) and G3: control group (the animals were not subjected either to biopsy or to surgery). On the 20 day after biopsy, the presence of adhesion strands between the sites of skin incision and testicle was evaluated by palpation. Adhesion strands were found in three testicles (15%) in G1 and in two testicles (10%) in G2. One hundred days after biopsy, orchiectomy was carried out and the material collected was assessed for subcutaneous (SC) and/or tunica vaginalis adhesions. G3 did not present any abnormality. Groups G1 and G2 presented four testicles each (20%) with adhesion between the tunics at biopsy site. On the other hand, subcutaneous adhesions were found once (5%) in G1 and three times (15%) in G2. Fibrin glue showed to be of easy application, required short postoperative monitoring, presented fast and good-quality healing property and tended to reduce formation of subcutaneous adhesion

The acquisition of dominance and ovulatory capacity was evaluated in follicles from cows that were carriers or half-sibling noncarriers of the Trio allele. Follicle size at acquisition of follicular dominance was determined by evaluating whether follicles ovulate after GnRH challenge (ovulatory capacity-experiment 1) and by determination of intrafollicular concentrations of estradiol and free insulin like growth factor 1 (IGF1) and relative mRNA expression of cytochrome P450 family 19 subfamily A member 1 (CYP19A1), luteinizing hormone/choriogonadotropin receptor (LHCGR), and pappalysin 1 (PAPPA, previously known as pregnancy-associated plasma protein A, pappalysin 1) in granulosa cells from follicles of different sizes (experiment 2). Ovulatory capacity developed in follicles at 8.3 mm (50% ovulatory capacity) in noncarriers but at smaller sizes (5.5 mm) in Trio carriers. Similarly, in experiment 2, follicles of Trio carriers acquired a dominant phenotype, as determined by intrafollicular estradiol and CYP19A1, LHCGR, and PAPPA mRNA expression in granulosa cells, at significantly smaller sizes but at a similar time after wave emergence. Overall, dominance/ovulatory capacity was acquired when follicles of Trio carriers were ∼30% the size (volume basis) of follicles in noncarriers. In addition, follicles in Trio carriers appear to acquire dominance in a hierarchal manner, as demonstrated by the progressively greater number of follicles with a dominant phenotype between days 2 and 4 after wave emergence. Thus, results from this study provide further support for a physiological model in which selection of multiple follicles in Trio allele carriers is characterized by acquisition of dominance at a smaller follicle size but at a similar time in the follicular wave with multiple follicles acquiring dominance in a hierarchal sequence.

The present study aimed to assess anti-T. gondii antibodies in sheltered and free-roaming cats within a university campus that has an overlapping population of humans and livestock. A total of 51 cats were tested for anti-T. gondii antibodies using the indirect immunofluorescent antibody test. Overall, 8/51 cats (15.7%) were seropositive. Cats were more likely to be seropositive when free-roaming (p= 0.008) and with presence of skin lesions (p= 0.042), and less likely with < 1 year of age (p= 0.021), probably due to higher environmental exposure and infected prey consumption. The presence of seropositive free-roaming cats whose areas overlapped those occupied by humans and livestock may suggest an increased on-campus chance of T. gondii occurrence.

No abstract