Use of serum amyloid A in equine medicine and surgery

Serum amyloid A (SAA) has become an indispensable part of the management of equine patients in general practice and specialized hospital settings. Although several proteins possess acute phase properties in horses, the usefulness of SAA exceeds that of other acute phase proteins. This is due to the highly desirable kinetics of the equine SAA response. SAA concentrations exhibit a rapid and pronounced increase in response to inflammation and a rapid decline after the resolution of inflammation. This facilitates the detection of inflammatory disease and real-time monitoring of inflammatory activity. SAA may be used in all stages of patient management: (1) before diagnosis (to rule in/rule out inflammatory disease), (2) at the time of diagnosis (to assess the severity of inflammation and assist in prognostication), and (3) after diagnosis (to monitor changes in inflammatory activity in response to therapy, with relapse of disease, or with infectious/inflammatory complications). By assessing other acute phase reactants in addition to SAA, clinicians can succinctly stage inflammation. White blood cell counts and serum iron concentration change within hours of an inflammatory insult, SAA within a day, and fibrinogen within 2–3 days; the interrelationship of these markers thus indicates the duration and activity of the inflammatory condition. Much research on the equine SAA response and clinical use has been conducted in the last decade. This is the prerequisite for the evidence-based use of this analyte. However, still today, most published studies involve a fairly low number of horses. To obtain solid evidence for use of SAA, future studies should be designed with larger sample sizes.     

Exploratory Study of Potato Cultivar Differences in Sensory and Hedonistic Applicability Tests

From a potato cultivar breeding database including 2,143 named cultivars and clones, 11 cultivars that spanned the major variation in cultivar quality were selected for subsequent sensory and hedonistic applicability tests. A tailor-made sensory profile of the cultivars was developed for four different cooking procedures: boiled, mashed, oven-fried and oven-cooked potatoes. A sensory profile consisted of the four to five most important sensory attributes, and the data was combined with the applicability data using multivariate data analysis. Ultimately, the variation in eating quality was evaluated in a hedonistic test with expert evaluation of applicability. Three gourmet chefs prepared the different cultivars as boiled potatoes, mashed potatoes, baked potatoes and oven-fried potatoes and evaluated the cultivars’ applicability, while a sensory panel consisting of nine judges evaluated the sensory quality. The multivariate data analysis revealed a significant diversity amongst the cultivars for the different cooking procedures. A single PCA bi-plot was able to provide a simple and clear overview of the gastronomic diversity and possible applications of the different potato cultivars.     

Bioaccumulation of melamine in catfish muscle following continuous, low-dose, oral administration

In this study, catfish muscle was analyzed for melamine (MEL) and cyanuric acid (CYA) residues following experimental feeding with low doses of MEL and MEL and CYA (MEL+CYA) and with the insoluble melamine-cyanurate complex (MEL=CYA). Catfish were daily fed 0.1 mg/kg BW of MEL for 15, 28, or 42 days, 0.1 mg/kg BW of MEL+CYA for 28 days, 2.5 mg/kg BW of MEL+CYA for 14 days, or 400 mg/kg BW of MEL=CYA for 3 days. Residues in the tissue were determined by LC-MS/MS. MEL was extracted with acidic acetonitrile, followed by defatting with dichloromethane, and isolated with cation exchange solid phase extraction (SPE). For CYA analysis, fish were extracted with dilute acetic acid, defatted with hexane, and cleaned up with a graphitic carbon SPE. Catfish fed 0.1 mg/kg BW of MEL reached a maximum muscle residue concentration of 0.33 ± 0.04 mg/kg (ppm) after 28 days of continuous feeding. The same concentration was found for MEL+CYA feeding at the 0.1 mg/kg BW level for 28 days. Feeding at 2.5 mg/kg BW of MEL+CYA yielded muscle concentrations above the 2.5 mg/kg level of concern for most of the study fish. Finally, catfish fed high levels of the MEL=CYA complex (400 mg/kg BW) accumulated relatively little MEL in the muscle (0.14 ± 0.07 mg/kg) and, unlike treatment with MEL+CYA, did not form renal melamine-cyanurate crystals. Appreciable concentrations of CYA were not detected in any of the muscles tested. These studies provide data to model the bioaccumulation of triazine residues into edible fish tissue as a result of the continuous consumption of adulterated feed.     

Nutritional and Chemical Composition of By-Product Fractions Produced from Wet Reduction of Individual Red Salmon (Oncorhynchus nerka) Heads and Viscera

There is growing interest for fishmeals and oils made from utilizing different fish by-products (heads, viscera, frames, etc.) that come directly from the commercial processing line. The major components of fish processing waste from salmon filleting operations are heads and viscera. In order to maximize the utilization of these individual by-products, the different fractions were evaluated. Analysis of essential amino acids in fishmeal showed significant differences in all essential amino acids except lysine. Differences were also noted in the levels of minerals, fatty acid methyl esters, biogenic amines, and fat soluble vitamins. The largest difference observed was in the level of retinol in the oil extracted from heads (8.9 ± 1.0 μg/g oil) and viscera (26.9 ± 3.8 μg/g oil). Head processing resulted in more lipids and cake, while the majority of viscera became stickwater. Results suggest that the fishmeal produced from different by-product parts can result in different nutritional values for feed or food ingredients.     

Validating an empiric sulfadiazine–trimethoprim dosage regimen for treatment of Escherichia coli and Staphylococcus delphini infections in mink (Neovison vison)

Antimicrobial agents are used extensively off‐label in mink, as almost no agents are registered for this animal species. Pharmacokinetic (PK) and pharmacodynamic (PD) data are required to determine antimicrobial dosages specifically targeting mink bacterial pathogens. The aims of this study were to assess, in a PKPD framework, the empirical dosage regimen for a combination of trimethoprim (TMP) and sulfadiazine (SDZ) in mink, and secondarily to produce data for future setting of clinical breakpoints. TMP and SDZ PK parameters were obtained experimentally in 22 minks following IV or oral administration of TMP/SDZ (30 mg/kg, i.e. 5 mg/kg TMP and 25 mg/kg SDZ). fAUC/MIC with a target value of 24 hr was selected as the PKPD index predictive of TMP/SDZ efficacy. Using a modeling approach, PKPD cutoffs for TMP and SDZ were determined as 0.062 and 16 mg/L, respectively. By incorporating an anticipated potentiation effect of SDZ on TMP against Escherichia coli and Staphylococcus delphini, the PKPD cutoff of TMP was revised to 0.312 mg/L, which is above the tentative epidemiological cutoffs (TECOFF) for these species. The current empirical TMP/SDZ dosage regimen (30 mg/kg, PO, once daily) therefore appears adequate for treatment of wild‐type E. coli and S. delphini infections in mink.     

The genetic organisation of the capsule biosynthesis region of Actinobacillus pleuropneumoniae serotypes 1, 6, 7, and 12

The aim of the present study was to investigate the organisation of the genes (cps) involved in biosynthesis the capsular polysaccharide (CPS) of Actinobacillus pleuropneumoniae serotypes 6, 7, and 12 and to compare these to the corresponding genes previously described in other A. pleuropneumoniae serotypes. In serotypes 6 and 7 the sequenced DNA regions comprised five and four open reading frames, respectively, designated cps6ABCDE and cps7ABCD, whereas the sequenced DNA region in serotype 12 comprised only two open reading frames designated cps12AB. At the amino acid level, CpsA, CpsB, and CpsC of A. pleuropneumoniae serotypes 2, 6, 7, and 8 contained a high degree of homology. At the amino acid level Cps6D revealed a high degree of homology to Cps8D, whereas Cps7D contained a high degree of homology to the Cps2D. The deduced gene product of the partially sequenced cps6E gene showed no homology to any deduced gene products of any cps genes of A. pleuropneumoniae investigated so far. None of the deduced gene products of the cps genes involved in encapsulation of A. pleuropneumoniae serotypes 2, 6, 7, and 8 revealed homology to the deduced gene products of the cps genes of serotypes 1, 5A, and 12. For some genes, a local homology was found to genes probably involved in teichoic acid synthesis in other bacteria. The results obtained revealed a high degree of homology among the genes involved in CPS biosynthesis for serotypes 2, 6, 7, and 8 and a different group of homologous cps genes for serotypes 1 and 12. In some serotype 7 strains, including the serotype 7 reference strain, WF83, the cps genes were not located adjacent to the genes responsible for CPS export (cpx), probably due to genetic rearrangements.     

Concentrations of serum amyloid A in serum and synovial fluid from healthy horses and horses with joint disease

OBJECTIVE: To determine serum amyloid A (SAA) concentrations in serum and synovial fluid from healthy horses and horses with joint disease and assess the effect of repeated arthrocentesis on SAA concentrations in synovial fluid. Animals-10 healthy horses and 21 horses with various types of joint disease. PROCEDURES: Serum and synovial fluid samples were obtained from each horse. In 5 of the 10 healthy horses, arthrocentesis was repeated 9 times. Concentrations of SAA were determined via immunoturbidometry. RESULTS: Serum and synovial fluid SAA concentrations were less than the assay detection limit in healthy horses and did not change in response to repeated arthrocentesis. Synovial fluid SAA concentrations were significantly higher in horses with suspected bacterial joint contamination or infectious arthritis, or tenovaginitis than in healthy controls, and serum concentrations were significantly higher in horses with infectious conditions than in the other groups. Neither serum nor synovial fluid SAA concentrations in horses with low-inflammation joint conditions differed significantly from those in healthy controls. Concentrations of SAA and total protein in synovial fluid were significantly correlated. CONCLUSIONS AND CLINICAL RELEVANCE: Synovial fluid SAA concentration was a good marker of infectious arthritis and tenovaginitis and appeared to reflect changes in inflammatory activity. The advantages of use of SAA as a marker include the ease and speed of measurement and the fact that concentrations in synovial fluid were not influenced by repeated arthrocentesis in healthy horses. Further study of the SAA response in osteoarthritic joints to assess its usefulness in diagnosis and monitoring of osteoarthritis is warranted.