Research Note: Comparison of chicken blood chemistry and electrolyte parameters between the portable i-STAT1 clinical analyzer and VetScan VS2 serum biochemistry panel using Hy-Line commercial white-egg laying hens.

The i-STAT1 clinical analyzer has become an increasingly popular tool in clinical production animal medicine as it can provide pen-side results in a cost effective and timely manner when compared to standard benchtop serum biochemistry blood gas and chemistry analyses. This study compares the results of the portable Abbott i-STAT1 analyzer and the Abaxis VetScan VS2 for glucose (Glu, mg/dL), ionized Ca (mmol/L), Na (mmol/L), and K (mmol/L) values. Three genetically distinct commercial varieties (CV) of Hy-Line white-egg laying hens are used in this study (Hy-Line W-36, Hy-Line W-80, and Hy-Line W-80+). Thirty blood samples (n = 10 per CV) were obtained in the production house from the brachial vein and concurrently analyzed by the i-STAT1 portable device. Serum from 22 of these same samples was analyzed via VetScan VS2, a benchtop serum clinical biochemistry analyzer, using VetScan Avian/Reptilian Profile Plus reagent rotors. A paired T-test was used to test for statistical differences in means between the 2 instruments for each of the parameters. Parameters with significant mean differences were then subject to correlation and regression analysis to further evaluate relationships between the results from the 2 methods. Significant differences between means were found for Glu, Na, and K levels. Ca levels were found to be not directly comparable by the 2 analysis instruments. This comparison elucidates the importance of clinical analyzer validations when applying different strategies of diagnostic medicine in poultry.

Establishment of Hy-Line commercial laying hen whole blood gas and biochemistry reference intervals utilizing portable i-STAT1 clinical analyzer.

Blood gas and biochemistry reference intervals were established for 3 genetically distinct commercial varieties (CVs) of Hy-Line laying hens: 2 brown-egg layers (Hy-Line Brown, Hy-Line Silver Brown) and a tint-egg layer (Hy-Line Sonia) utilizing the i-STAT1 analyzer. Each respective variety of laying hen was sampled on a replicate cycle of 2 wk for a total of 6 replicates (35 to 46 wk of age). Blood samples were obtained in the production house from the brachial vein, and subsequently analyzed by the i-STAT1 portable device. i-STAT1 clinical analyzer reports blood gas and biochemistry values for the following parameters: pH, partial pressure of carbon dioxide (pvCO2, mm Hg), partial pressure of oxygen (pvO2, mm Hg), bicarbonate (HCO3, mmol/L), base excess (BE, mmol/L), saturation of oxygen on hemoglobin (sO2%), glucose (Glu, mg/dL), sodium (Na, mmol/L), potassium (K, mmol/L), total concentration of carbon dioxide (TCO2, mmol/L), ionized calcium (iCa, mmol/L), hematocrit (Hct % packed cell volume [PCV]), hemoglobin (Hb, g/dL). A total of 1,800 individual hen i-STAT1 records were utilized in the establishment of reference interval values for the 13 parameters between the 3 CVs. Statistical analysis via ANOVA and Tukey's test revealed significant line differences for all 13 blood gas and chemistry parameters measured, with particularly interesting results in iCa. The blood gas and chemistry parameters collected in this study will serve as reference intervals to set the framework for potential future correlations to genetic markers, physiological abnormalities, and production performance.

Commercial Hy-Line W-36 pullet and laying hen venous blood gas and chemistry profiles utilizing the portable i-STAT®1 analyzer.

Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm.

A survey of the hatchability of broiler and turkey eggs in the United States from 1985 through 2005.

A survey was conducted of the hatchability of broiler and turkey eggs set in US commercial hatcheries from 1985 through 2005. In 2005, a total of 11 billion broiler eggs and 343 million turkey eggs were set, compared with 5.6 billion broiler eggs and 258 million turkey eggs set in 1985. These numbers represented increases of 98 and 33% in the respective totals of broiler and turkey eggs set since 1985. Hatchability during this period ranged from 79 to 82% for broiler eggs and 76 to 80% for turkey eggs. Advances in nutrition, genetic selection, and management of broiler and turkey flocks during this time period did not result in an increase in hatchability. The economic loss associated with the lack of improved hatchability in the year 2005 was in excess of $500 million.

Selection and characterization of pre-mRNA splicing enhancers: identification of novel SR protein-specific enhancer sequences.

Splicing enhancers are RNA sequences required for accurate splice site recognition and the control of alternative splicing. In this study, we used an in vitro selection procedure to identify and characterize novel RNA sequences capable of functioning as pre-mRNA splicing enhancers. Randomized 18-nucleotide RNA sequences were inserted downstream from a Drosophila doublesex pre-mRNA enhancer-dependent splicing substrate. Functional splicing enhancers were then selected by multiple rounds of in vitro splicing in nuclear extracts, reverse transcription, and selective PCR amplification of the spliced products. Characterization of the selected splicing enhancers revealed a highly heterogeneous population of sequences, but we identified six classes of recurring degenerate sequence motifs five to seven nucleotides in length including novel splicing enhancer sequence motifs. Analysis of selected splicing enhancer elements and other enhancers in S100 complementation assays led to the identification of individual enhancers capable of being activated by specific serine/arginine (SR)-rich splicing factors (SC35, 9G8, and SF2/ASF). In addition, a potent splicing enhancer sequence isolated in the selection specifically binds a 20-kDa SR protein. This enhancer sequence has a high level of sequence homology with a recently identified RNA-protein adduct that can be immunoprecipitated with an SRp20-specific antibody. We conclude that distinct classes of selected enhancers are activated by specific SR proteins, but there is considerable sequence degeneracy within each class. The results presented here, in conjunction with previous studies, reveal a remarkably broad spectrum of RNA sequences capable of binding specific SR proteins and/or functioning as SR-specific splicing enhancers.

Multiple distinct splicing enhancers in the protein-coding sequences of a constitutively spliced pre-mRNA.

We have identified multiple distinct splicing enhancer elements within protein-coding sequences of the constitutively spliced human beta-globin pre-mRNA. Each of these highly conserved sequences is sufficient to activate the splicing of a heterologous enhancer-dependent pre-mRNA. One of these enhancers is activated by and binds to the SR protein SC35, whereas at least two others are activated by the SR protein SF2/ASF. A single base mutation within another enhancer element inactivates the enhancer but does not change the encoded amino acid. Thus, overlapping protein coding and RNA recognition elements may be coselected during evolution. These studies provide the first direct evidence that SR protein-specific splicing enhancers are located within the coding regions of constitutively spliced pre-mRNAs. We propose that these enhancers function as multisite splicing enhancers to specify 3' splice-site selection.

Identification of a plant serine-arginine-rich protein similar to the mammalian splicing factor SF2/ASF.

We show that the higher plant Arabidopsis thaliana has a serine-arginine-rich (SR) protein family whose members contain a phosphoepitope shared by the animal SR family of splicing factors. In addition, we report the cloning and characterization of a cDNA encoding a higher-plant SR protein from Arabidopsis, SR1, which has striking sequence and structural homology to the human splicing factor SF2/ASF. Similar to SF2/ASF, the plant SR1 protein promotes splice site switching in mammalian nuclear extracts. A novel feature of the Arabidopsis SR protein is a C-terminal domain containing a high concentration of proline, serine, and lysine residues (PSK domain), a composition reminiscent of histones. This domain includes a putative phosphorylation site for the mitotic kinase cyclin/p34cdc2.

Immunoscintigraphy in intraocular malignant melanoma.

Immunoscintigraphy of malignant tumours has become an encouraging tool in nuclear medicine. Early diagnosis of small lesions is mandatory for successful cancer therapy. The scintigraphic detectability of small lesions (less than 1 cm in diameter) by immunoscintigraphy is shown in 39 patients suffering from ocular tumours (37 malignant choroidal melanoma, two benign choroidal naevi) using 99Tcm-labelled F(ab')2 fragments of the anti-melanoma monoclonal antibody 225.28S; this antibody recognizes the high molecular weight melanoma-associated antigen. No adverse effects were observed. In terms of true-positive results, single photon emission computed tomography (SPECT) proved to be superior to planar scans (73% versus 41% true-positive results).