Evaluation of the effectiveness of Duddingtonia flagrans and Monacrosporium thaumasium in the biological control of gastrointestinal nematodes in female bovines bred in the semiarid region

Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L₃ and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures.     

Higher feeding diets effects on age and liveweight gain at puberty in crossbred Nelore × Hereford heifers

This study was conducted to determine the age and liveweight at puberty of 120 crossbred beef heifers submitted to four diets to achieve predetermined weight gains (kg/day): 0.5 (G500; n?=?32), 0.75 (G750; n?=?32), 1.0 (G1000; n?=?29), and 1.25 (G1250; n?=?27). Animals were classified depending on their level of crossing between Nelore (N) and Hereford (H): 25%N-75%H, 37.5%N-63.5%H, 43.7%N-56.7%H, 50%N-50%H, and 75%N-25%H. Reproductive evaluation was performed at the beginning and at the end of the experimental period by ultrasonography and hormone analysis. The average age and liveweight at puberty were 388.0?±?1.9 days and 331.4?±?1.3 kg, respectively. Animals from the 25%N-75%H group reached puberty earlier than heifers from other genetic groups supplemented with G1250 diet (P?<?0.05). Heifers with higher degree of Nelore (75%N-25%H) fed with G1000 diet showed estrus 42 days prior to mating, but only 57 % reached puberty at mating (P?<?0.05). Heifers with follicles of higher diameter reached puberty (P?<?0.05) earlier. Higher average daily weight gain showed a positive effect on follicular diameter and IGF-I level at puberty (P?<?0.01). Concentrations of GH were lower in heifers fed G1250 compared to G1000 diet (P?<?0.05). There was a significant interaction between nutritional level and insulin levels at puberty (P?<?0.01). We demonstrated the relationship between IGF-I and average daily gain on the onset of puberty in heifers. In conclusion, heifers submitted to the higher feeding level showed a higher follicular diameter and were younger at puberty.     

Brazilian foot and mouth disease status and meat exportation to the European Union

The aim of this study was to define the differences between the Brazilian states that export and do not export meat to the European Union (EU) and to identify the variables that are important to meet the export requirements. Infrastructure and computerization of the control of animal transit in Brazil that impact on regional health status were evaluated and linked to other variables such as status for foot and mouth disease (FMD) and qualification to export meat to EU. Variables related to transit control of bovines implemented by the state agencies of animal health and inspection in each Brazilian state were evaluated. Using a discriminant analysis, four variables were selected that explained the variation between Brazilian states that were “free” and “not free” of FMD while another four were selected to explain the variation between the zones “approved” and “not approved” to export meat to the EU, including number of official veterinarians, total transit of bovines and buffaloes, total number of animal transit certificates issued for bovine and buffaloes at the state or zone level, and total number of municipalities in the state or zone. It was possible to correctly discriminate between “free” and “not free” FMD states or zones. Variables related to animal transit are important in assessing the state for the classification of animal health situation and for EU approval for the exportation of meat.     

Detection of anti-Leishmania infantum antibodies in sylvatic lagomorphs from an epidemic area of Madrid using the indirect immunofluorescence antibody test

An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.     

Mutants in the lipopolysaccharide of Brucella ovis are attenuated and protect against B. ovis infection in mice

Brucella spp. are Gram-negative bacteria that behave as facultative intracellular parasites of a variety of mammals. This genus includes smooth (S) and rough (R) species that carry S and R lipopolysaccharides (LPS), respectively. S-LPS is a virulence factor, and mutants affected in the S-LPS O-polysaccharide (R mutants), core oligosaccharide or both show attenuation. However, B. ovis is naturally R and is virulent in sheep. We studied the role of B. ovis LPS in virulence by mutating the orthologues of wadA, wadB and wadC, three genes known to encode LPS core glycosyltransferases in S brucellae. When mapped with antibodies to outer membrane proteins (Omps) and R-LPS, wadB and wadC mutants displayed defects in LPS structure and outer membrane topology but inactivation of wadA had little or no effect. Consistent with these observations, the wadB and wadC but not the wadA mutants were attenuated in mice. When tested as vaccines, the wadB and wadC mutants protected mice against B. ovis challenge. The results demonstrate that the LPS core is a structure essential for survival in vivo not only of S brucellae but also of a naturally R Brucella pathogenic species, and they confirm our previous hypothesis that the Brucella LPS core is a target for vaccine development. Since vaccine B. melitensis Rev 1 is S and thus interferes in serological testing for S brucellae, wadB mutant represents a candidate vaccine to be evaluated against B. ovis infection of sheep suitable for areas free of B. melitensis.     

Strangulation of the small intestine by an anomalous congenital band in a yearling

Strangulating obstruction of the small intestine by anomalous mesenteric bands is an uncommon cause of colic in horses. The most commonly reported bands are mesodiverticular bands that are embryological remnants of the vitelline arteries. Despite the congenital nature of the anomaly, a wide age range of horses can be affected. This report describes a case of small intestinal strangulating obstruction caused by an unusual, anomalous congenital band attached to the ileocaecal fold in a yearling colt. Information including case background, history, clinical, laboratory, surgical and pathological findings is described.     

Post-fire production of mushrooms in Pinus pinaster forests using classificatory models

This study was aimed at describing post-fire mushroom production in a Mediterranean ecosystem dominated by Pinus pinaster Ait. in the northwest of Spain and assessing the results by classificatory models. During the autumn periods of 2003–2006, fruit bodies from 115 fungal taxa were collected in burned and unburned areas and were further grouped into the following categories: saprotrophic/mycorrhizal; and edible/non-edible. After wildfires, a significant reduction in the number of fungal species and fruit body biomass production was observed. Based on this relevant information, the first simple classificatory model for this aim is provided. Nine alternative models based on classifications according to combinations of edibility and functional groups were fitted, and four fruiting body biomass production classes were defined as possible responses. As explanatory factors, time after fire and climatic variables significantly related to fruit body production were included. The best predictive results were obtained for edible and edible-mycorrhizal models, for which the correct classification rate of production classes was between 92 and 85 %. Moreover, the models obtained were applied to analyse the effect of time after fire on fungal production. Mycorrhizal and edible fungal production after fire was classified into the lowest class, whereas saprotrophic and non-edible species followed a contrary trend. The classificatory models can be useful to optimise management and harvest of these increasingly appreciated non-timber forest resources.     

A review of extracellular virulence product of Vibrio species important in diseases of cultivated shrimp

Shrimp aquaculture is an important industry that experiences significant losses from Vibrio species, especially at the larval and juvenile stages. Proteinaceous virulence factors, including alkaline proteases, metalloproteases, cysteine proteases and alkaline serine proteases, have been identified as important elements in Vibrio pathogenesis. This review summarizes current knowledge regarding the principal pathogenic Vibrio species in shrimp, with emphasis on relevant exotoxins and their modes of action, principal characteristics and molecular database. This pathogenic factors and their relation with other molecules produced by microorganisms may be help to understand the virulence mechanisms present in Vibrio strain.     

Behavioral response to selected feed attractants and stimulants in Pacific white shrimp, Litopenaeus vannamei

Nine commercial feeding attractants and stimulants for Litopenaeus vannamei were evaluated by observation of behavioral responses in animals allotted in one Y-maze aquarium apparatus. In the validation phase, fishmeal–Brazilian origin (FMBO); fishmeal–Peruvian origin (FMPO); blood meal (BM), meat and bone meal (MBM), squid meal (SM), fish oil (FO) and fish solubles (FS) were evaluated. There was also a control without stimulatory raw material. The tested materials were included at 3% in neutral gelatin pellets (wet basis). In each behavioral observation, two different ingredients were offered at the same time in equal quantities, being allotted in the end of each chamber's arm. In Phase II after system validation, the following commercial attractants were tested: 80% crude protein (CP) vegetable dried biomass (VDB₈₀), 68% CP vegetable dried biomass + glutamate + betaine (VDB₆₈), complex of amino acids (alanine, valine, glycine, proline, serine, histidine, glutamic acid, tyrosine and betaine) with enzymatically digested bivalve mollusk (CAA), condensed fish soluble protein (CFSP), squid liver meal (SLM), betaine (Bet), dried fish solubles–low biogenic amines (DFS_LB), dried fish solubles–high biogenic amines (DFS_HB) and whole squid protein hydrolysate (WSPH). Attractants were used at a 3% level wet basis with neutral gelatin, without any additional ingredient source available. The best four commercial attractants from this phase (CAA, CFSP, SLM and WSPH) were compared under 0.5% and 1.0% levels. In Phase I of the study, a higher percentage of choices were observed for FMPO and FMBO. BM and FO were the least chosen ingredients. In Phase II, the worst results were observed for Bet, DFS_HB and, mainly, for VDB₈₀ and VDB₆₈. When two-by-two comparisons were performed, results suggested that CFSP and CAA were the best commercial attractants tested. In the last phase, both CFSP and CAA at 1.0% level were significantly more chosen by shrimp than CFSP (0.5%), SLM (0.5 or 1.0%) or WSPH (0.5 or 1.0%). At both 0.5% and 1.0% levels, shrimp spent a similar amount of time feeding on CFSP and CAA. However, only CAA was statistically better than SLM and WSPH together. Further work is required to better elucidate the chemical drivers of chemostimulation for L. vannamei for each one of the attractants tested.