Effects of postpartum milking strategy on plasma mineral concentrations and colostrum, transition milk, and milk yield and composition in multiparous dairy cows.

The effects of postpartum milking strategy on plasma mineral concentrations, blood ß-hydroxybutyrate (BHB) concentration, and colostrum, transition milk, and first monthly test milk yield and composition were evaluated in 90 multiparous Jersey and Jersey × Holstein crossbreed cows from a commercial farm. Before first postpartum milking, cows were randomly assigned to the following milking strategies, implemented during the first 2 d postpartum: twice-a-day milking (M2, standard industry practice, milking every 12 h; n = 22), once-a-day milking (M1, milking every 24 h; n = 24), restricted milking (MR, 3-L milking every 12 h; n = 21), and delayed milking (MD, no milking for the first 24 h, and milking every 12 h afterward; n = 23). Blood samples for total plasma Ca, P, and Mg determination were collected from enrollment every 4 h up to 48 h, and at 3 d in milk. Blood BHB concentration was determined at 3 and 11 d in milk. Colostrum and transition milk yields were recorded, and samples were collected at each study milking for IgG and somatic cell count (SCC) determinations. Information for first monthly test milk yield and composition was obtained from the Dairy Herd Improvement Association. Statistical analyses were conducted using generalized multiple linear and Poisson regressions with Dunnett adjustment and M2 as reference group for mean comparisons. Overall, plasma Ca concentration within 48 h after enrollment was higher for MD (2.17 mmol/L), tended to be higher for MR (2.15 mmol/L), and was similar for M1 (2.09 mmol/L) compared with M2 cows (2.06 mmol/L). No statistically significant differences compared with M2 cows were observed for plasma P and Mg concentrations. Colostrum and transition milk and total Ca harvested within 48 h after enrollment were lower for M1, MR, and MD compared with M2 cows. The MD strategy prevented harvesting colostrum with >50 g of IgG/L. No statistically significant effects were detected on plasma mineral concentrations at 3 DIM, blood BHB concentration, colostrum and transition milk SCC within 48 h after enrollment, or milk yield, energy-corrected milk yield, and SCC at first monthly test. Our results suggest that postpartum plasma Ca concentration may be influenced by postpartum milking strategy, without interfering with future milk yield and udder health. Further studies should evaluate whether the proposed milking strategies in early postpartum affect production, reproduction, or health.

Microbial Control of Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae) in Brazilian Rubber Tree Plantations: a Brief Historical Account and Identification of Entomopathogenic Fungi by Means of Multigene Phylogeny.

Over the last decades, a few fungal species have been mentioned in the literature associated with the rubber tree lace bug, Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae). The rubber plantation area treated with these biocontrol agents has been steady since the 1990s, estimated in 10,000-15,000 ha per year. A few large-scale rubber operations, one biocontrol company, and three government-owned laboratories were, and currently one still is, involved in their commercialization. One species, currently referred to as Sporothrix insectorum, has been historically deployed in biocontrol applications in Brazilian rubber farms. However, L. heveae-infecting isolates have only been identified through morphological examinations; therefore, proper molecular assessments are needed for accurate identifications. Hence, DNA of six L. heveae-infecting isolates (five of which have been deployed in field applications) were extracted and sequenced. Multigene phylogeny found that both Simplicillium lanosoniveum and Cordyceps (formerly Isaria) sp. have been sprayed on rubber plantations to manage L. heveae populations, although the former is the only one currently applied. Simplicillium lanosoniveum and Cordyceps sp. have no relation whatsoever to true Sporothrix species associated with human and animal diseases. Therefore, our molecular data may encourage biocontrol companies to register mycoinsecticides targeting L. heveae. We also added unpublished historical accounts after contacting key contributors to the launching of this not so well-known biocontrol program in the 1980s.

Technical note: Glucose concentration in dairy cows measured using 6 handheld meters designed for human use.

The objective was to evaluate the precision and accuracy of 6 handheld glucose meters, designed for human use [Accu-Chek Aviva Plus (AC), Roche Diabetes Care, Mannheim, Germany; Aga Matrix (AM), AgaMatrix Inc., Salem, NH; Contour Next (CT), Bayer HealthCare LLC, Leverkusen, Germany; FreeStyle Precision Neo (FS), Abbott Diabetes Care Ltd., Alameda, CA; Nova Max Plus (NM), Nova Biomedical Corporation, Waltham, MA; and Precision Xtra (PX), Abbott Diabetes Care Ltd., Witney, UK] to measure blood glucose concentration in dairy cows. Blood samples from Jersey and Jersey × Holstein crossbreed cows (n = 97 for all; except CT, n = 71) were collected and analyzed in triplicate using the 6 handheld glucose meters evaluated. Plasma glucose was also measured with the laboratory reference method (hexokinase glucose-6-phosphate dehydrogenase). Based on the intra-assay coefficient of variation (CV), precision varied across handheld glucose meters: AC (2.2%), CT (4.0%), PX (4.7%), FS (5.6%), AM (6.2%), and NM (6.7%). Lin's concordance correlation coefficients between handheld glucose meters and the reference method were 0.75 for FS, 0.74 for PX, 0.62 for AC, 0.55 for CT, 0.53 for NM, and 0.48 for AM. Based on Passing-Bablok regression, the AM and PX meters showed bias in the measurements of blood glucose. Bland-Altman plots indicated a negative bias (FS = -0.25 mmol/L; CT = -0.60 mmol/L) or a positive bias (AM = 0.29 mmol/L; PX = 0.33 mmol/L; NM = 0.52 mmol/L; AC = 0.65 mmol/L) between handheld glucose meters and the reference method. All handheld glucose meters evaluated had wide limits of agreement (LoA) ranging from -0.18 to 1.47 mmol/L (AC, narrowest LoA) to -1.25 to 1.82 mmol/L (AM, widest LoA). Bias was the major contributor to the total observed error (TEobs), accounting for 81.5% of the TEobs in AC, 72.0% in CT, 64.9% in AM, 61.1% in NM, 57.8% in PX, and 56.2% in FS. Overall, although some handheld meters (AC, CT, and PX) showed satisfactory precision, none were accurate measuring glucose. Future studies should evaluate whether incorporating algorithms designed for cattle can improve accuracy and precision of handheld glucose meters.

A nonconventional two-stage fermentation system for the production of aerial conidia of entomopathogenic fungi utilizing surface tension.

AIM: To describe a new approach in which production of conidia of an entomopathogenic fungus takes place on the surface of an unstirred shallow liquid culture kept in nonabsorbent wells distributed in plastic sheets resembling a honeycomb. METHODS AND RESULTS: First, liquid incubation time and medium composition for production of Beauveria bassiana aerial conidia were optimized. Wells inoculated with Sabouraud dextrose yeast extract produced 2·2 × 108 conidia per cm2 of liquid surface following 5 days of incubation. Finally, tests were carried out in a prototype comprised of stacked plastic sheets in a cylindrical container. Conidia production on liquid culture surface varied from 1·2 to 1·6 × 109 conidia per ml of fermented broth. Germination rates and insect activity towards Tenebrio molitor larvae were not negatively affected when compared to conidia produced on solid medium. CONCLUSIONS: The two-stage fermentation process here described, based on a simple nonabsorbent inert support, has potential for the application in the production of aerial conidia of B. bassiana and other fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: Aerial conidia are the most extensive propagule type used in commercial mycopesticides, traditionally produced by solid-state fermentation (SSF). The industrial applications and other important benefits of the two-stage fermentation process here described may overcome some hurdles inherent to SSF aiming for the production of aerial conidia. Additionally, production consistency is increased by the use of chemically defined medium, and the better control of the environmental conditions could allow for more reproducible industrial batches.

Description of Males from Three Species of Eumeninae (Hymenoptera, Vespidae).

The external morphology and genitalia of the males of Stenonartonia mimica (Kohl 1907), Sphaeromenes discrepatus Giordani Soika, 1978 and Gamma bolivianum flavior Giordani Soika, 1990 are described for the first time.

Genetic diversity and pathogenicity of Metarhizium spp. associated with the white grub Phyllophaga capillata (Blanchard) (Coleoptera: Melolonthidae) in a soybean field.

Phyllophaga capillata (Blanchard) was recently described as a soybean pest in Brazil. The occurrence of Metarhizium spp. associated with adults and their pathogenicity were investigated. Natural prevalence of Metarhizium anisopliae was 0.51% in adults collected by light trap. Most Metarhizium isolates were identified as Metarhizium robertsii, although M. anisopliae sensu stricto and a few unidentified isolates were also found. Bioassays with representative isolates selected from different genetic groups resulted in ≤5.6% confirmed mortality against larvae and adults, suggesting low potential of microbial control of this pest by use of indigenous Metarhizium isolates.

Efficiency of bioaugmentation in the removal of organic matter in aquaculture systems.

Several techniques are currently used to treat effluents. Bioaugmentation is a new bioremediation strategy and has been employed to improve effluent quality by treating the water during the production process. This technology consists basically of the addition of microorganisms able to degrade or remove polluting compounds, especially organic matter and nutrients. The objective of this study was to assess the effects of bioaugmentation on some parameters of organic matter and on the performance of juvenile tilapias in an intensive aquaculture production system. The combination of two bacterial consortiums in a complete randomized design was employed in a factorial analysis with two factors. Statistical differences between treatments were analyzed by the analysis of variance (ANOVA) and Tukey test at the 5% level. One of the treatments, heterotrophic bacterial supplementation, was able to reduce biochemical oxygen demand (BOD) by 23%, dissolved organic carbon (DOC) by 83.7% and phytoplanktonic biomass by 43%. On the other hand, no damage was done to either the physical-chemical indicators of water quality or to the growth performance of juvenile tilapias assessed in this study.

Differential susceptibility of adults and nymphs of Blattella germanica (L.) (Blattodea: Blattellidae) to infection by Metarhizium anisopliae and assessment of delivery strategies.

Microbial insecticides for cockroach control, such as those containing entomopathogenic fungi, may be an alternative to reduce contamination by chemicals in housing and food storage environments. Virulence of isolate ESALQ1037 belonging to the Metarhizium anisopliae complex against nymphs and adults of Blattella germanica (L.), and its infectivity following exposure of insects to a contaminated surface or to M. anisopliae-bait were determined under laboratory conditions. Estimated LD50 15 d following topical inoculation was 2.69 x 10(5) conidia per adult, whereas for nymphs the maximum mortality was lower than 50%. Baits amended with M. anisopliae conidia had no repellent effect on targets; adult mortality was inferior to 25%, and nymphs were not susceptible. All conidia found in the digestive tract of M. anisopliae-bait fed cockroaches were unviable, and bait-treated insects that succumbed to fungal infection showed a typical mycelial growth on mouthparts and front legs, but not on the hind body parts. As opposed to baits, the use of a M. anisopliae powdery formulation for surface treatment was effective in attaining high mortality rates of B. germanica. Both nymphs and adults were infected when this delivery strategy was used, and mycelia growth occurred all over the body surface. Our results suggest that the development of powders or similar formulations of M. anisopliae to control B. germanica may provide faster and better results than some of the strategies based on baits currently available.

Tyrosine phosphorylation of platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) in mechanically stimulated vascular endothelial cells.

Fluid flow triggers signal transducing events, modulates gene expression, and remodels cytoskeletal structures in vascular endothelial cells (ECs). However, the primary steps of mechanoreception are still unknown. We have recently reported that a glycoprotein is rapidly tyrosine-phosphorylated in bovine ECs exposed to fluid flow or osmotic shock. Here were cloned a 3.4 kb cDNA encoding this protein and found that this was bovine PECAM-1. The tyrosine-phosphorylation level of PECAM-1 immunoprecipitated from mechanically stimulated bovine or human ECs increased. The PECAM-1 phosphorylation was not induced by reagents that triggered Ca2+ mobilization in ECs. An autophosphorylatable band comigrating with c-Src was co-immunoprecipitated with anti-PECAM-1, and c-Src phosphorylated and bound to a GST fusion protein containing the PECAM-1 cytoplasmic domain. A spliced mRNA form lacking amino acid residues 703-721 in the cytoplasmic domain was also expressed in bovine ECs, c-Src neither phosphorylated nor bound to the fusion protein containing the spliced PECAM-1 cytoplasmic domain which lacked one (Tyr 713) of the six tyrosine residues in the PECAM-1 cytoplasmic domain. These results suggest that the YSEI motif containing Tyr 713 is the Src phosphorylation/binding site. Our study is the first demonstration of inducible tyrosine phosphorylation of PECAM-1 and suggests involvement of PECAM-1 and Src family kinases in the sensing/signal transduction of mechanical stimuli in ECs.