Use of a jugular vein graft in a modified Blalock-Taussig procedure in dogs

OBJECTIVE: To determine whether autologous jugular veins provide functional grafts with high 30-day patency rates in an experimental model of systemic-to-pulmonary shunting performed with a modified Blalock-Taussig procedure. ANIMALS: 15 healthy Beagles. PROCEDURE: A segment of the left jugular vein was implanted between the left subclavian and pulmonary arteries. Echocardiograms were obtained prior to surgery, at day 4 to 7, and at day 30 after surgery. Selective angiograms were performed immediately after surgery and on day 30. Oximetric shunt calculations were made via terminal angiography prior to euthanasia. Gross and histologic evaluations of the grafts were conducted. RESULTS: Grafts were patent in 12 of 15 dogs 30 days after surgery as assessed via auscultation, color Doppler ultrasonography, angiography, and histologic examination. Echocardiographic analysis revealed compensatory eccentric left ventricular hypertrophy. Mean pulmonary-to-systemic flow ratio was 1.5:1. Histologic evidence of endothelialization of the anastomotic sites and vein graft arterialization was detectable at 30 days. CONCLUSIONS AND CLINICAL RELEVANCE: Autologous jugular vein grafts were effectively used to create a systemic-to-pulmonary shunt by use of a modified Blalock-Taussig procedure. High patency, ready accessibility, low cost, and theoretical adaptative remodeling during patient growth make autologous jugular vein grafts a valuable alternative to synthetic materials.     

Effect of freezing and microbial growth on myoglobin derivatives of beef.

The effect of freezing and bacterial growth on the discoloration of beef was assessed by measuring myoglobin derivatives myoglobin (MB), oxymyoglobin (MBO(2)), and metmyoglobin (METMB) on the surfaces of fresh and frozen-thawed packaged beef cuts stored at 2 degrees C and analyzed after 0, 3, 6, 9, and 12 days of storage. MB, MBO(2), and METMB concentrations were measured spectrophotometrically. Frozen-thawed beef samples experienced less "blooming" (conversion of MB to MBO(2)) and more rapid discoloration than fresh cuts during storage. By day 3, >20% METMB was formed in the frozen-thawed samples, whereas the fresh samples reached this value after day 6 of storage. The rates of MB oxidation were similar (P > 0.05) for sterile and frozen-thawed inoculated (Pseudomonas fluorescens at a rate of 1.5 colony forming units/cm(2).cm(2) area) samples from day 0 through day 6 of storage. For storage periods of less than a week, bacterial growth is not a major cause of meat discoloration. After day 6, the high bacterial growth rate resulted in a rapid increase in METMB formation. Possible mechanisms for MB oxidation in frozen-thawed beef are suggested.     

Animal Transmissible Spongiform Encephalopathies and Genetics

The genotype of the host plays a crucial role in the pathogenesis of transmissible spongiform encephalopathies (TSEs). In this respect, the most important factor is represented by the gene of the prion protein (PrP). The present work summarizes the currently available knowledge on the genetic basis of TSEs focusing, in particular, on sheep scrapie. Interest in this disease has grown markedly following the discovery of bovine spongiform encephalopathy, both for scientific and health reasons. In Italy, specific research grants from the Ministry of Health and the National Research Council (CNR), together with cooperation between the Istituto Superiore di Sanità and the Istituti Zooprofilattici Sperimentali, have allowed us to study the PrP genotype and to investigate the genetic susceptibility to scrapie in the most important Italian sheep breeds, with special reference to Sarda, Comisana and Massese. The PrP genotype in relation to scrapie susceptibility was also studied in goats of Ionica breed.     

Comparison of optical indicators for potato crop nitrogen status assessment including novel approaches based on leaf fluorescence and flavonoid content

Some phenolic compounds are proposed as good indicators of crop nitrogen status (CNS). This research compared the use of leaf flavonoid content (LFC) as a potential indicator for evaluating potato CNS with other recognized indicators linked to leaf chlorophyll content (LCC). Three-year trials were conducted in Belgium on two potato cultivars including increasing nitrogen rates. Optical sensors (Dualex, Multiplex, Hydro N-tester, Cropscan) were used to evaluate LFC and/or LCC. Plant tissue samples were analyzed to calculate the biomass nitrogen concentration and the nitrogen nutrition index. The indicators were evaluated based on four criteria: the sensitivity, the earliness of the diagnosis, the accuracy, and the specificity. Apart from the low specificity to nitrogen, which can be improved by the use of a within-field reference plot, the LFC (combined with LCC or individually) matched the required criteria and could be suggested as a valuable indicator for assessing potato CNS.     

Genetic diversity and differentiation of Nile tilapia (Oreochromis niloticus) revealed by DNA microsatellites

To assess the genetic diversity of Nile tilapia Oreochromis niloticus, a total of 250 fish from five Egyptian populations were genotyped using six microsatellite markers. Heterozygosity and Wright's F‐statistics (F_IS, F_ST, and F_IT) were calculated to determine the genetic variation within and between these populations. Observed heterozygosities were in the range of 0.4 (Burullus) to 0.96 (Qena), with F_IS values ranging from 0.082 to 0.282. The mean F_ST showed that approximately 96.5% of the genetic variation was within‐population and 3.5% was among populations. Standard genetic distances were used to classify the five populations into two major groups. The deeper lotic river Nile populations of Assuit and Cairo formed one group and the shallow less lotic Delta lakes populations of Manzalla and Burullus formed the second group, with the upstream Nile Qena population being an outgroup. The findings from the current study help understanding of the broad‐scale population structuring of the Nile tilapia (O. niloticus) allowing the population groupings identified to act as potential sources of genetic variation. These populations could be included in future Marker‐Assisted‐Selection programs for economically desired production traits.     

Exploring the impacts of different fasting and refeeding regimes on Nile tilapia (Oreochromis niloticus L.): growth performance,histopathological study,and expression levels of some muscle growth-related genes

Fish Physiology and Biochemistry - The current study investigated how different fasting and refeeding regimes would impact Nile tilapia growth performance, histopathological examination, and gene...     

Morphological and Genomic Differences Between Cutting and Racing Lines of Quarter Horses

To investigate morphological and genomic differences between cutting and racing lines of Quarter Horses, 120 racing and 68 cutting animals of both sexes, registered at the Brazilian Association of Quarter Horse Breeders, were used. Blood samples were collected, and the following physical traits were measured: weight; height at withers; body length; length of the shank, pastern, rump, head, and neck; and chest, shank, and hoof circumference. For analysis of genomic differences, 54,602 single-nucleotide polymorphisms (SNPs) were genotyped using the Equine SNP50 BeadChip, and the quality of individual and SNP genotype data were evaluated. The fixation index, F_ST, was used to identify genome regions that were altered in the lines by selection. The results showed significant differences between the lines in all physical traits. Quality control led to the exclusion of four cutting animals with a call rate of <0.95. After filtering, 12,544, 13,815, and 13,370 SNPs were excluded for the whole population (n = 184), the 120 racing animals, and the 64 cutting animals, respectively. The number of informative polymorphisms detected in each line and in the whole population indicated that the Equine SNP50 BeadChip can be used in genetic studies of Quarter Horses. The fixation index, F_ST, identified 2,558 genome regions that may have been modified by divergent selection.     

In vitro evaluation,in vivo quantification,and microbial diversity studies of nutritional strategies for reducing enteric methane production

The main objective of the present work was to study nutritive strategies for lessening the CH₄ formation associated to ruminant tropical diets. In vitro gas production technique was used for evaluating the effect of tannin-rich plants, essential oils, and biodiesel co-products on CH₄ formation in three individual studies and a small chamber system to measure CH₄ released by sheep for in vivo studies was developed. Microbial rumen population diversity from in vitro assays was studied using qPCR. In vitro studies with tanniniferous plants, herbal plant essential oils derived from thyme, fennel, ginger, black seed, and Eucalyptus oil (EuO) added to the basal diet and cakes of oleaginous plants (cotton, palm, castor plant, turnip, and lupine), which were included in the basal diet to replace soybean meal, presented significant differences regarding fermentation gas production and CH₄ formation. In vivo assays were performed according to the results of the in vitro assays. Mimosa caesalpineaefolia, when supplemented to a basal diet (Tifton-85 hay Cynodon sp, corn grain, soybean meal, cotton seed meal, and mineral mixture) fed to adult Santa Ines sheep reduced enteric CH₄ emission but the supplementation of the basal diet with EuO did not affect (P > 0.05) methane released. Regarding the microbial studies of rumen population diversity using qPCR with DNA samples collected from the in vitro trials, the results showed shifts in microbial communities of the tannin-rich plants in relation to control plant. This research demonstrated that tannin-rich M. caesepineapholia, essential oil from eucalyptus, and biodiesel co-products either in vitro or in vivo assays showed potential to mitigate CH₄ emission in ruminants. The microbial community study suggested that the reduction in CH₄ production may be attributed to a decrease in fermentable substrate rather than to a direct effect on methanogenesis.