Evaluation of an oscillometric blood pressure monitor for use in anesthetized cats

OBJECTIVE: To determine accuracy of an oscillometric blood pressure monitor used over a wide range of pressures in anesthetized cats. DESIGN: Prospective study. ANIMALS: 6 healthy cats. PROCEDURE: 4 female cats and 2 male cats that weighed 2.7 to 4.5 kg (5.9 to 9.9 lb) and were 2 to 8 years old were anesthetized. Blood pressure was measured directly with an arterial catheter placed in the right femoral artery and indirectly from the left antebrachium by use of an oscillometric monitor. A series of diastolic arterial pressure (DAP), mean arterial pressure (MAP), and systolic arterial pressure (SAP) measurements were obtained during hypotension, normotension, and hypertension. Values obtained indirectly and directly were compared. RESULTS: The oscillometric monitor was accurate for DAP and MAP throughout the entire pressure range and met the standards of the Association for the Advancement of Medical Instrumentation (mean +/- SD difference from values obtained directly, < or = 5 +/- 8 mm Hg). The SAP was increasingly underestimated with increasing overall pressure; mean differences from direct measurements were -5.2, -12.1, and -17.7 mm Hg during hypo-, normo-, and hypertension, respectively. Standard deviations for SAP were all < or = 8 mm Hg. The monitor gave readings during all attempts. The direct blood pressure recording system appeared to perform well with neither under- nor overdamping. CONCLUSIONS AND CLINICAL RELEVANCE: Except for a minor underestimation of SAP during normo- and hypertension, the oscillometric monitor yielded reliable and easily obtainable blood pressure measurements in anesthetized cats.     

Bovine NK cells acquire cytotoxic activity and produce IFN-gamma after stimulation by Mycobacterium bovis BCG- or Babesia bovis-exposed splenic dendritic cells

Early interactions of innate immune cell populations, such as dendritic cells (DC) and natural killer (NK) cells, can affect the ability of the acquired immune response to control infection of intracellular microorganisms. In this study, we investigated the activation of bovine NK cells by CD13(+) splenic DC stimulated with either Mycobacterium bovis BCG or Babesia bovis merozoites. Splenic DC were used either immediately after selection (cytokine(-)) or after exposure to GM-CSF, IL-4 and Flt3L for 72 h (cytokine(+)). Phenotypic analyses showed up-regulation of MHCII, CD80 and CD86 on cytokine(+) DC when compared to cytokine(-) DC. Purified NK cells (CD335(+)CD3(-)CD2(+/-)CD8alpha(+/-)) were co-cultured with microbial-exposed cytokine(-) DC or cytokine(+) DC in either transwell or cell-to-cell format and NK cell IFN-gamma production and cytotoxicity were assessed. NK cell IFN-gamma production was dependent on cell-to-cell contact. Microbial-stimulated cytokine(+) DC induced significantly more IFN-gamma production from NK cells than cytokine(-) cells. In contrast, cytotoxicity and perforin up-regulation were more pronounced in NK cells cultured with cytokine(-) DC than cytokine(+) DC. Therefore, activation of bovine NK cells by microbial-stimulated CD13(+) splenic DC is influenced by the maturation state of the DC suggesting different roles for the splenic DC during disease-induced maturation.     

The effect of bovine viral diarrhea virus infections on health and performance of feedlot cattle

The aim of this study was to investigate the effect of bovine viral diarrhea virus (BVDV) infections (unapparent acute infections and persistent infections) on the overall health and performance of feedlot cattle. Calves from 25 pens (7132 calves) were enrolled in the study. Overall and infectious disease mortality rates were significantly higher (P < 0.05) in pens categorized at arrival as positive for type I BVDV and lower in pens that were positive for type II BVDV than in negative pens. Mortality attributed to BVDV infection or enteritis was significantly more common (P < 0.05) in the pens containing persistently infected (PI) calves than in pens not containing PI calves (non-PI pens). There were no statistically detectable (P > or = 0.05) differences in morbidity, overall mortality, average daily gain, or the dry matter intake to gain ratio between PI and non-PI pens. Although type-I BVDV infections in feedlots appear to contribute to higher mortality rates, the presence of PI calves alone does not appear to have a strong impact on pen-level animal health and feedlot performance.     

Effects of supplemental protein type on productivity of primiparous beef cows

Effects of supplemental degradable (DIP) and undegradable (UIP) intake protein on forage intake, BW change, body condition score (BCS), postpartum interval to first estrus, conception rate, milk production and composition, serum metabolites and metabolic hormones, and calf gain were determined using 36 primiparous Gelbvieh x Angus rotationally crossed beef cows. On d 3 postpartum, cows (average initial BW = 495 +/- 10 kg and BCS = 5.5 +/- 0.1) were randomly assigned to one of three dietary supplements (12 cows/treatment). Date of parturition was evenly distributed across treatment (average span of calving date among treatments = 2.4 +/- 2.5 d). Individually fed (d 3 through 120 postpartum) dietary supplements were 0.82 kg of corn and 0.23 kg of soybean meal per day (DIP), the DIP + 0.12 kg of blood meal and 0.13 kg of corn gluten meal per day (DIP + UIP), and 0.82 kg of corn, 0.07 kg of blood meal, and 0.08 kg of corn gluten meal per day in an isonitrogenous replacement of soybean meal (UIP IsoN). Cows had ad libitum access to native grass hay (8.5% CP) and trace-mineralized salt. Total OM intake was greater (P = 0.06) for DIP + UIP than UIP IsoN cows. At 30 d postpartum, DIP + UIP cows produced more milk than UIP IsoN, with DIP being intermediate; however, at 60 d postpartum, DIP + UIP and DIP cows were not different, but both had greater milk production than UIP IsoN (treatment x day interaction; P = 0.08). A treatment x day interaction (P = 0.06) for BCS resulted from DIP + UIP cows having the greatest BCS at 60, 90, and 120 d d postpartum and DIP having greater BCS than UIP IsoN cows only on d 60 postpartum. Serum insulin concentrations were highest (treatment x day interaction; P = 0.09) for DIP + UIP cows at 30 d postpartum but did not differ among treatment thereafter. Serum insulin-like growth factor-binding protein (IGFBP)-2 (34 kDa) and -3 (40 and 44 kDa) were greatest (P < 0.0003) for DIP cows. Serum urea-N concentrations were greater (P < 0.01) in DIP + UIP cows than in either DIP or UIP IsoN cows. However, postpartum interval to first estrus, conception rate, and calf weaning weights were unaffected (P = 0.35, 0.42, and 0.64, respectively) by treatment. Although UIP in addition to or in replacement of DIP affected milk production and blood metabolites, the productivity of these primiparous beef cows was not altered. Thus, the type of supplemental protein does not seem to influence productivity of primiparous beef cows in production systems with conditions similar to our experimental conditions.     

In silico prediction of Gallibacterium anatis pan-immunogens

The Gram-negative bacterium Gallibacterium anatis is a major cause of salpingitis and peritonitis in commercial egg-layers, leading to reduced egg production and increased mortality. Unfortunately, widespread multidrug resistance and antigenic diversity makes it difficult to control infections and novel prevention strategies are urgently needed. In this study, a pan-genomic reverse vaccinology (RV) approach was used to identify potential vaccine candidates. Firstly, the genomes of 10 selected Gallibacterium strains were analyzed and proteins selected on the following criteria; predicted surface-exposure or secretion, none or one transmembrane helix (TMH), and presence in six or more of the 10 genomes. In total, 42 proteins were selected. The genes encoding 27 of these proteins were successfully cloned in Escherichia coli and the proteins expressed and purified. To reduce the number of vaccine candidates for in vivo testing, each of the purified recombinant proteins was screened by ELISA for their ability to elicit a significant serological response with serum from chickens that had been infected with G. anatis. Additionally, an in silico prediction of the protective potential was carried out based on a protein property prediction method. Of the 27 proteins, two novel putative immunogens were identified; Gab_1309 and Gab_2312. Moreover, three previously characterized virulence factors; GtxA, FlfA and Gab_2156, were identified. Thus, by combining the pan-genomic RV approach with subsequent in vitro and in silico screening, we have narrowed down the pan-proteome of G. anatis to five vaccine candidates. Importantly, preliminary immunization trials indicated an in vivo protective potential of GtxA-N, FlfA and Gab_1309.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0080-0) contains supplementary material, which is available to authorized users.     

Accumulation of Sapogenin Conjugates and Histological Changes in the Liver and Kidneys of Lambs Suffering from Alveld,a Hepatogenous Photosensitization Disease of Sheep Grazing Narthecium ossifragum

Sixteen lambs exhibiting hepatogenous photosensitization (alveld) after grazing pasture containing Narthecium ossifragum and seven nonphotosensitized lambs grazing the same pastures were studied. All the alveld-affected lambs revealed liver damage dominated by single cell necrosis, portal fibroplasia and bile duct proliferation. Crystalloid clefts were demonstrated in the bile ducts of two and in the hepatocytes and Kupffer cells of nine photosensitized lambs. Plasma bilirubin concentration was severely increased in ten of the cases of alveld whereas the activity of aspartate aminotransferase was moderately to severely increased in seven cases. The activity of glutamate dehydrogenase was moderately elevated in one of the photosensitized lambs. The main histopathological findings in the kidneys from the alveld-affected lambs were dilated tubules, often with eosinophilic material in the tubular lumina. Regenerative changes were seen in a large proportion of the renal sections. Elevated plasma concentrations of urea and creatinine, and the renal histopathological changes, suggested that the photosensitized lambs had been through a phase of renal injury. Analysis of the free and conjugated sapogenin content in liver tissue and bile was performed by gas chromatography–mass spectrometry. There were significantly higher concentrations of conjugated episapogenins in both the liver and bile in the alveld-affected lambs than in the nonphotosensitized lambs.     

Selection of virulent populations of Meloidogyne javanica by repeated cultivation of Mi resistance gene tomato rootstocks under field conditions

Field trials were conducted in a plastic house artificially infested with an avirulent population of Meloidogyne javanica to determine the durability of the resistance mediated by the Mi gene in tomato rootstocks after repeated cultivation for three consecutive years. Treatments included an experimental rootstock cv. PG76 ( Solanum lycopersicum  ×  Solanum sp.), a commercial rootstock cv. Brigeor ( S. lycopersicum  ×  S. habrochaites ), a resistant tomato cv. Monika ( S. lycopersicum ), and a susceptible cv. Durinta ( S. lycopersicum ). Based on the reproduction index (RI: number of eggs per g root on the resistant cultivar divided by number of eggs per g root on the susceptible cultivar × 100), rootstock cv. PG76 responded as highly resistant (RI = 7%) after the first cropping cycle (3·4 nematode generations), showed intermediated resistance (RI = 33%) after the second cropping cycle (3·3 generations), and was fully susceptible (RI = 94%) after the third cycle (3·3 generations). In contrast, rootstock cv. Brigeor and resistant cv. Monika retained intermediate resistance levels (RI = 41 and 25%, respectively) after the third cropping cycle. Virulent nematode populations were rapidly selected from an avirulent one after repeated cultivation of resistant tomatoes under field conditions. Bioassays conducted under controlled conditions confirmed that selection for virulence occurred more rapidly in plots with cv. PG76 followed by Brigeor and Monika. The nematode population in the field not exposed to Mi resistance remained avirulent to Mi genotypes. The genetic background of the resistant rootstocks and the frequency of cropping were critical factors for the appearance of virulent nematode populations. Irrespective of nematode infection, all resistant tomatoes yielded more than the susceptible cultivar.     

Cardiac glycoside poisoning in sheep caused by Urginea physodes (Jacq.) Bak. and the isolated physodine A

Urginea physodes (Jacq.) Bak., a species closely related to or possibly synonymous with U. pusilla, is described and its distribution given. Four bufadienolides were isolated from U. physodes and the approximated LD50 and cumulative effect of some of them determined in guinea pigs. The most toxic one proved to be mildly cumulative. Typical signs of acute cardiac glycoside poisoning, involving the locomotory, gastro-intestinal, respiratory and cardiac system, were seen in the field cases and/or were experimentally induced by the plant. Similar signs could also be induced by injecting the isolated bufadienolide, physodine A, to a sheep.     

A quantitative approach to analysing cortisol response in the horse

The cortisol response to glucocorticoid intervention has, in spite of several studies in horses, not been fully characterized with regard to the determinants of onset, intensity and duration of response. Therefore, dexamethasone and cortisol response data were collected in a study applying a constant rate infusion regimen of dexamethasone (0.17, 1.7 and 17 μg/kg) to six Standardbreds. Plasma was analysed for dexamethasone and cortisol concentrations using UHPLC‐MS/MS. Dexamethasone displayed linear kinetics within the concentration range studied. A turnover model of oscillatory behaviour accurately mimicked cortisol data. The mean baseline concentration range was 34–57 μg/L, the fractional turnover rate 0.47–1.5 1/h, the amplitude parameter 6.8–24 μg/L, the maximum inhibitory capacity 0.77–0.97, the drug potency 6–65 ng/L and the sigmoidicity factor 0.7–30. This analysis provided a better understanding of the time course of the cortisol response in horses. This includes baseline variability within and between horses and determinants of the equilibrium concentration–response relationship. The analysis also challenged a protocol for a dexamethasone suppression test design and indicated future improvement to increase the predictability of the test.     

Cardiopulmonary and sedative effects of intravenous or epidural methadone in conscious dogs

Cardiopulmonary and sedative effects of intravenous or epidural methadone were compared. Six beagles were randomly assigned to group MIV (methadone 0.5 mg/kg IV + NaCl 0.9% epidurally) or MEP (methadone 0.5 mg/kg epidurally + NaCl 0.9% IV). Cardiopulmonary, blood gas and sedation were assessed at time (T) 0, 15, 30, 60, 120, 240 and 480 min after drug administration. Compared to T0, heart rate decreased at T15–T120 in MIV (p < .001) and T15–T240 in MEP (p < .05); mean arterial pressure was reduced at T15–T60 in MEP (p < .01); respiratory rate was higher at T15 and T30 in both groups (p < .05); pH was lower at T15–T120 in MIV (p < .01) and T15, T30 and T120 in MEP (p < .05); PaCO₂ was higher at T15–T60 in MIV (p < .01) and T15, T30 and T120 in MEP (p < .01); sedation scores were higher at T15 and T30 in MIV and T15–T60 in MEP (p < .05). At T120 and T240, sedation score was higher in group MEP compared with group MIV (p < .01) In conclusion, cardiopulmonary and sedative effects of identical methadone doses are similar when administered IV or epidurally to conscious healthy dogs.