Integrative phylogenetic, phylogeographic and morphological characterisation of the Unio crassus species complex reveals cryptic diversity with important conservation implications.

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.

Who do we gain? Enhancement of blood supplies by additional testing for donors who travel.

AIMS/OBJECTIVES: To describe the impact of additional testing on the England blood supply. BACKGROUND: The blood service for England, NHS Blood and Transplant, applies a system of deferral and testing to donors with potential exposure to Chagas disease, malaria and West Nile virus; however, testing costs must be justified. Here, we describe the donations and donors gained by testing. METHODS: Donation testing results and demographic data on donors in England where additional testing was applied were analysed in 2012-2016. The total number and proportion of donations tested, reactive and confirmed positive were calculated. Proportions of donors requiring additional tests were calculated by ethnic group for first-time and repeat donors. RESULTS: Additional testing for travel was applied to 3·5% of NHSBT blood donations between 2012 and 2016. Over 98% of these tests were non-reactive. Only malaria tests were confirmed positive, in 1·7% of donations tested. In first-time donors, 45 and 40% of Asian and Black donors required an additional test, respectively, mainly for malaria. Testing for West Nile virus increased from 1·5% in 2012 to 2·2% of donations in 2016. CONCLUSION: The majority of additional tests were screened negative, allowing approximately 64 000 donations to be released for issue annually. Donors most affected by malaria testing were more likely to have rare blood groups and be targeted for recruitment, whereas those given West Nile virus testing were mainly regular donors required for continuity of supply. These data show differences in the characteristics of donors by test and can be used to inform decisions about additional testing and deferrals.

Collimated blue and infrared beams generated by two-photon excitation in Rb vapor.

Utilizing two-photon excitation in hot Rb vapor we demonstrate the generation of collimated optical fields at 420 and 1324 nm. Input laser beams at 780 and 776 nm enter a heated Rb vapor cell collinear and circularly polarized, driving Rb atoms to the 5D(5/2) state. Under phase-matching conditions coherence among the 5S(1/2)→5P(3/2)→5D(5/2)→6P(3/2) transitions produces a blue (420 nm) beam by four-wave mixing. We also observe a forward and backward propagating IR (1324 nm) beam, due to cascading decays through the 6S(1/2)→5(1/2) states. Power saturation of the generated beams is investigated by scaling the input powers to greater than 200 mW, resulting in a coherent blue beam of 9.1 mW power, almost an order of magnitude larger than previously achieved. We measure the dependences of both beams in relation to the Rb density, the frequency detuning between Rb ground-state hyperfine levels, and the input laser intensities.

Temperature dependence of Rb 5P fine-structure transfer induced by 4He collisions.

Employing ultrafast laser excitation and time-correlated single-photon counting, we have measured the fine-structure transfer between Rb 5P states induced by collisions with 4He buffer gas at temperatures up to 150 °C. The temperature dependence of the binary cross section agrees with earlier measurements. Our data show that the temperature dependence of the three-body rate is about the same as that of the binary rate. The three-body rate can be described as arising from the reduction of the rubidium fine-structure splitting due to nearby helium atoms.

Low genetic diversity in Polish populations of sibling ant species: Lasius niger (L.) and Lasius platythorax Seifert (Hymenoptera, Formicidae).

We present preliminary data on mitochondrial DNA diversity within and among populations of the ants Lasius niger and Lasius platythorax in Poland. Phylogenetic analysis based on the mitochondrial DNA markers: cytochrome c oxidase subunit I (cox1) and 16S ribosomal RNA (16S rRNA) confirms the species status of L. niger and L. platythorax. Intraspecific variability is low in both species, which might be a result of severe bottlenecks and rapid postglacial expansion into Central Europe.

Enhancement of Rb fine-structure transfer in 4He due to three-body collisions.

Using ultrafast laser excitation and time-correlated single-photon counting techniques, we have measured the collisional mixing rates between the rubidium 5(2)P fine-structure levels in the presence of (4)He gas. A nonlinear dependence of the mixing rate with (4)He density is observed. We find Rb fine-structure transfer is primarily due to binary collisions at (4)He densities of < or = 10(19) cm(-3), while at greater densities, three-body collisions become significant. We determine a three-body collisional transfer rate coefficient (5(2)P(3/2) --> 5(2)P(1/2)) of 1.25(9)x10(-32) cm(6)/s at 22 degrees C.

Collinear laser spectroscopy of francium using online rubidium vapor neutralization and amplitude modulated lasers.

Performing collinear laser spectroscopy on low intensity radioactive beams requires sensitive detection techniques. We explain our apparatus to detect atomic resonances in neutralized (208-210)Fr ion beams at beam energies of 5 keV and intensities of 10(5) s(-1). Efficient neutralization (> or = 80%) is accomplished by passing the beam through a dense Rb vapor. Increased detection efficiency is achieved by amplitude modulating the exciting laser to decrease the scattered light background, allowing fluorescence detection only when the laser is near its minimum in the modulation cycle. Using this technique in a collinear geometry we achieve a background reduction by a factor of 180 and a signal-to-noise increase of 2.2, with the lifetime of the atomic state playing a role in the efficiency of this process. Such laser modulation will also produce sidebands on the atomic spectra which we illustrate.

Preharvest feed withdrawal affects liver lipid and liver color in broiler chickens.

An Iowa grain processor attempted to alter the typical 12-h preharvest fasting period by giving broilers cornstarch derivative pellets and water for 6 h followed by 6 h of no feed or water. After slaughter, plant food inspectors determined that livers from the treatment group were lighter in color than normal, and consequently a significant number of chicken carcasses were condemned for human consumption. The study reported herein was conducted to determine the effects of fasting or 3 feeding programs applied before processing on liver color, liver lipids, and liver glycogen of broilers. Dietary treatment groups consisted of 1) full-fed control broilers, 2) fasted broilers, 3) maltodextrin-fed broilers, and 4) and chickens given maltodextrin and methionine. Full-fed chickens had lighter liver coloration than chickens without access to feed for 6 or 12 h immediately prior to slaughter (P < 0.05). Lightness values for livers from full-fed control chickens (L* = 54.41) were 38% higher than those for livers from fasted broilers (L* = 39.30). Lighter liver colors in full-fed broilers were associated with higher hepatic lipid concentrations (6.38%) and more total liver lipid (4.96 g/liver) than was found in broilers without feed for 12 h. In contrast, darker livers from fasted broilers had lower levels of lipid (4.42%) and less total lipid (2.68 g/liver) than the full-fed broilers. Feeding maltodextrin pellets resulted in liver colors that were lighter (P < 0.05) than those found in fasted chickens but darker (P < 0.05) than livers from full-fed broilers. If carbohydrate supplements are fed prior to slaughter, producers should notify processing plant officials so that inspectors do not interpret light livers as an abnormal physiological state.

Mitochondrial DNA differentiation between two forms of trout Salmo letnica, endemic to the Balkan Lake Ohrid, reflects their reproductive isolation.

Mitochondrial haplotype diversity in sympatric populations of Ohrid trout, Salmo letnica was investigated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mtDNA control region and ND1, ND3/4, ND5/6 segments. A 310 bp fragment at the 5' end, and a 340-572 bp fragment at the 3' end of the control region were sequenced from representatives of the populations studied. Based on pairwise comparison of the sequences, five new haplotypes were identified plus one identical with the brown trout Andalusian haplotype from the southern Iberian Peninsula. The combination of both RFLP and sequence data sets yielded a total of 10 composite haplotypes. A high degree of genetic subdivision between S. letnica typicus and S. letnica aestivalis populations was observed. The notion of a sympatric origin for the two morphs is discussed. Length variation of the mtDNA control region due to the presence of an 82 bp unit, tandemly repeated one to four times, in the region between the conserved sequence block-3 (CSB-3) and the gene for phenylalanine tRNA is reported. Further, we demonstrate that a single duplication of the approximately 82 bp repeat unit is a common element of the salmonid mitochondrial control region. The unique genetic structure of Ohrid trout represents a highly valuable genetic resource that deserves appropriate management and conservation.

Utilizing Solanum glaucophyllum alone or with phytase to improve phosphorus utilization in broilers.

Experiments were conducted to determine if Solanum glaucophyllum (SG), a plant containing a glycoside of 1,25-dihydroxyvitamin D, could be used as a feed additive to improve P utilization of broilers. SG leaves (1, 2.5, or 5 g/kg), 1,25-dihydroxyvitamin D (15 microg/kg), or Ca and P (to achieve a 0.92% Ca:0.65% P:0.41% nonphytate P control diet) were added to a 0.56% Ca/0.45% P/0.28% nonphytate P basal diet and fed to broilers from 7 to 28 d of age. Birds fed basal ration alone exhibited reduced weight gain, bone density, and bone mineral content when compared with birds fed the 0.92% Ca:0.65% P diet. Adding 5 g SG leaves or 15 microg of 1,25-dihydroxyvitamin D/kg to the basal diet increased body weight gain, plasma Ca and P, bone ash, and bone density above basal diet levels. Plasma P and weight gain of birds fed 5 g SG or 15 microg of 1,25-dihydroxyvitamin D/kg basal diet were equivalent to those observed in birds fed the 0.92% Ca:0.65% P diet. In experiment 2, the effect of higher doses of SG, as well as the additive effect of SG with 1,200 phytase units/kg diet, were examined in chicks fed a 0.59% Ca and 0.42% P basal diet. Two levels of SG leaves (7.5 g and 10 g), phytase, or both SG (7.5 g) and phytase were added per kilogram of basal diet. Adding SG or phytase to the basal diet increased weight gain, plasma Ca, plasma P, and bone mineral content over that observed in birds fed basal diet alone. Combining SG with phytase provided no significant gains in growth or bone parameters over treatment with phytase alone.

Effect of low-protein diets on growth performance and body composition of broiler chicks.

Three experiments were conducted to investigate effects of dietary manipulations to improve growth performance and whole-body composition of broiler chicks fed low-protein diets supplemented with crystalline amino acids. In all experiments, male chicks (1 d old) were fed a common corn-soybean meal diet (23% CP) for 7 d and subsequently allotted to treatment diets in a completely randomized design (10 chicks per floor pen, six replications). Chicks had free access to the isoenergetic diets (3,200 kcal MEn/kg) for 2 wk, after which chicks were weighed and then fasted for 24 h, and the whole-body DM, N, and ether extract contents of two chicks per pen (and six baseline chicks) were determined. In Experiment 1, Gln or Asn replaced 1% triammonium citrate in the low-protein diet (19% CP). In Experiments 2 and 3, dietary concentrations of crystalline essential and nonessential amino acids, respectively, were increased incrementally in the low-protein diets (19 to 20% CP). In all experiments, chicks fed low-protein diets grew slower, used feed less efficiently, and retained less N and more ether extract than chicks fed the control diets (P < or = 0.05), despite additions of crystalline Gln or Asn and despite increased dietary concentrations of crystalline essential and nonessential amino acids. Chicks fed low-protein diets excreted less N (P < 0.001) than did chicks fed the high-protein diets, and N excretion increased linearly (P < 0.001) with N intake. In summary, low-protein diets failed to support equal growth performance to that of high-protein control diets.

Prediction of whole-body composition from the whole-body dry matter percentage of three-week-old broiler chicks.

Whole carcasses of 3-wk-old broiler chicks from four independent experiments were analyzed for percentage of whole-body DM, ether extract, and CP. The percentage of whole-body ash was calculated by the difference among DM, ether extract, and CP. A linear relationship between percentage whole-body DM and percentage whole-body ether extract (P < 0.001; r2 = 0.798) was found, but no relationships were detected between percentage whole-body DM and percentage whole-body CP (P = 0.29; r2 = 0.010). The percentage of whole-body ash was moderately correlated with the percentage of whole-body DM (P = 0.04; r2 = 0.036). In conclusion, the percentage of whole-body ether extract of 3-wk-old broiler chicks can be predicted from the percentage of whole-body DM by using the prediction equation Y = 0.961x - 17.855. Neither the percentages of whole-body CP nor ash could be accurately predicted from the wholebody DM percentage.

Effects of vitamin E and C supplementation on performance, in vitro lymphocyte proliferation, and antioxidant status of laying hens during heat stress.

Vitamin E (dl-alpha-tocopheryl acetate) was evaluated for its effects on performance, lymphocyte proliferation, and antioxidation in layers during heat stress. In Trial 1, 25, 45, or 65 IU of vitamin E/kg were fed to four replicated pens (five hens/cage) of DeKalb Delta or Hy-Line W-36 per treatment starting at 20 wk of age. At 34 wk of age, hens were heat-stressed at diurnal temperature ranging from 21 C to 35 C for 3 wk. The performances of hens not exposed to heat stress were not influenced by supplemental vitamin E. Supplemental vitamin E did not affect egg production; however, egg mass was greater (P < 0.05) with supplementation of 65 IU of vitamin E/ kg during heat stress. Egg yolk was significantly increased (P < 0.04) when hens were fed 45 and 65 lU/kg compared with the control vitamin E level (25 lU/kg). Haugh units were higher (P < 0.01) for hens fed 65 IU of vitamin E/kg compared to 25 and 45 lU/kg. Lymphocyte proliferative responses to concanavalin A (Con A) and Salmonella typhimurium lipopolysaccharide (LPS) were greater (P < 0.0001) in hens fed 45 and 65 IU of vitamin E/kg during heat stress. Strain had no effect on any of the parameters measured. In Trial 2, a 2 x 2 factorial was designed to test effects of vitamin C in drinking water (0 and 1,000 ppm) and dietary vitamin E (25 and 65 IU/kg). Eight replications per treatment with four hens per replication cage were heat-stressed at constant temperature of 35 C for 3 wk. Egg production and egg mass were higher when hens were fed 65 IU of vitamin E/kg than when hens were fed 25 lU/kg (81.5 vs. 75.9%, P < 0.03 and 48.2 vs. 44.6 g, P < 0.03, respectively). Yolk solids weight for the 65 IU vitamin E/kg group was higher (P < 0.01) compared to the 25 IU/kg group. ConA and LPS mitogenic responses were greater in hens fed 65 IU of vitamin E (P < 0.001 or P < 0.003, respectively) or 1,000 ppm of vitamin C (P < 0.001 or P < 0.002, respectively). The combination of 65 IU vitamin E/kg and 1,000 ppm vitamin C showed the highest ConA and LPS mitogenic responses among the treatments. No interaction effects of the two vitamins on production measurements or lymphocyte proliferative responses were observed. TBA values in egg yolk and plasma of hens fed 65 IU of vitamin E/kg were lower (P < 0.0001) than those of hens that received 25 IU of vitamin E/kg. These results suggest that vitamin E supplementation at 65 IU/kg diet may enhance production, induction of in vitro lymphocyte proliferation by ConA and LPS, and antioxidant properties of egg yolks and plasma of White Leghorn hens during heat stress and that supplementation of 1,000 ppm vitamin C may further enhance in vitro lymphocyte proliferative responses of hens during heat stress.

Effect of dietary vitamin K1 on selected plasma characteristics and bone ash in young turkeys fed diets adequate or deficient in vitamin D3.

Three experiments were conducted to determine the effect of dietary vitamin K1 (K1) on selected plasma characteristics and bone ash in poults. In Experiment 1, diets were supplemented with 0, 0.5, 1.0, or 2.0 mg of K1/kg. All diets contained 1,650 IU of vitamin D3 (D3)/kg. Dietary K1 had no effect on tibia ash at 7 d or incidence of a severe, rickets-like condition. Tibia ash of poults fed 2.0 mg of K1/kg, however, was greater at 14 d of age than that of poults fed the basal diet. Dietary inclusion of 0.5 mg of K1/kg was as effective as 1 or 2 mg of K1/kg in reducing plasma prothrombin time. In Experiment 2, a 2 x 4 factorial arrangement was used consisting of 1,650 or 550 IU of D3/kg and 0.1, 0.45, 1.0, and 2.0 mg of K1/kg. Dietary D3 and K1 had no effect on bone ash. Dietary inclusion of 0.1 mg of K1/kg seemed to be enough to minimize plasma prothrombin time. In Experiment 3, dietary treatments consisted of a control (1,650 IU of D3 and 2.0 mg of K1/kg) and K1 concentrations of 0, 0.37, 2.28, or 5.33 mg/kg in diets containing 275 IU of D3/kg. Poults fed the low-D3 diet without K1 consumed less feed, gained less weight, and had increased plasma alkaline phosphatase activity, decreased inorganic phosphorus level, and decreased tibia ash (P < 0.05) compared with those of poults fed the control diet. Feed intake and body weight gain were improved, plasma alkaline phosphatase activity decreased, and plasma inorganic phosphorus increased or tended to increase when poults were fed the low-D3 diet supplemented with 0.37 or 2.88 mg of K1/kg compared with poults fed the low-D3 diet without K1 supplementation. Tibia ash of poults fed the low-D3 diet was not affected by K1 supplementation. The results of this research show that dietary K1 concentration had little, if any, effect on bone development in 1- to 14-d-old turkeys.

Dietary vitamin K1 requirement and comparison of biopotency of different vitamin K sources for young turkeys.

In a preliminary experiment, the inclusion of vitamin K1 (K1) at a dietary level of 0.1 mg/kg was as effective as 1 or 2 mg/kg in reducing plasma prothrombin time (PT). To obtain an estimate of the dietary K1 requirement and to compare the biopotency of different vitamin K sources for poults, three additional experiments were conducted. In Experiment 1, an incomplete factorial arrangement of treatments was used in which five dietary concentrations of K1 (0, 0.1, 0.25, 0.5, or 2.0 mg/kg) were tested and two concentrations of neomycin (0 or 75 mg/L) in drinking water were used in conjunction with 0, 0.1, and 0.5 mg of K1/kg of diet. Thus, we used a total of eight treatments. Each treatment was given to two pens of poults, with eight poults per pen. Prothrombin time and prothrombin concentration (PC) in plasma were not influenced by inclusion of neomycin in drinking water. The K1 requirement was estimated, on the basis of PT and PC, to be 0.099 and 0.13 mg/kg, respectively, in Experiment 1. Dietary K1 concentrations tested in Experiment 2 were 0, 0.08, 0.31, or 0.44 mg/kg. A similar protocol to that of Experiment 1 was used in this experiment. The results of Experiment 2 indicated that the dietary K1 requirement was 0.079 mg, based on the influence of dietary K1 on PT. In Experiment 3, dietary treatments consisted of the equivalent of 0.22, 0.55, or 1.11 microM of menadione equivalent/kg from vitamin K1, menadione dimethypyrimidinol bisulfite (MPB) or menadione nicotinamide bisulfite (MNB), respectively, and a control without supplementation of any vitamin K source. The results of Experiment 3 showed that the biopotency of K1 was greater than that of MPB or MNB. The biopotencies of MPB and MNB were similar, although MNB was more potent in reducing plasma PT when supplemented at the level of 0.1 mg of menadione/kg. A nadir of PT and a plateau of PC were evident with a dietary supplementation of MPB or MNB at a level of 0.25 mg of menadione/kg. Results of this research show that the dietary K1 requirement of young turkeys is in the range of 0.079 to 0.13 mg/kg, and ingestion of neomycin did not affect estimates of the requirement. The biopotency of vitamin K1 in reducing plasma PT and increasing plasma PC was greater than that of MPB or MNB. The biopotency of MNB was greater than that of MPB when menadione supplementation was equivalent to 0.10 mg of K1/kg.

Influence of two dietary fats on the composition of emu oil and meat.

Male and female emus were fed a diet rich in saturated fat (beef tallow) or a diet rich in unsaturated fat (soybean oil) until they weighed about 35 kg. Samples of subcutaneous and retroperitoneal adipose tissues and samples of six major meat cuts were taken for determination of composition. Emus fed the two different diets grew at similar rates, but the male emus had a higher percentage of carcass fat. The adipose tissue cells from males were larger than those from females. All six meat cuts averaged 2.2% fat, with the regular filet having the most and the inside and outside drums the least. Cholesterol concentration of all sizes of meat cuts averaged 32.2 mg/100 g meat. Diet did not influence cholesterol content of the rendered oil. Fan filets had the greatest concentration of cholesterol, and the inside and outside drums had the least. Source of dietary fat had no effect on fat and cholesterol content of the meats. Meat from emus fed beef tallow was more tender and juicy. Fan filets were the most tender meat, had the least intense flavor, and were the most flavorful. Untrained panelists were able to discriminate between emu meat and beef. Source of dietary fat did not influence the fatty acid compositions of the meats. As expected, the soybean oil-fed emus produced oil that was more polyunsaturated than did the tallow-fed emus.

Metabolizable energy value of conjugated linoleic acid for broiler chicks and laying hens.

Two experiments with broiler chicks and one experiment with laying hens were conducted to determine the MEn value of conjugated linoleic acid (CLA). In Experiment 1, for 8 d, 16-d-old chicks were fed diets in which 4, 8, or 12% of CLA Source A or 4, 8, or 12% of soybean oil (SO) was substituted for glucose. Dietary MEn increased linearly (P < or = 0.001) with increments of CLA Source A or SO. Regression analysis relating increases in dietary MEn and increments of the dietary fat sources showed that the MEn values of CLA Source A and SO, when evaluated separately, were 7,419 and 8,429 kcal/kg, respectively. In Experiment 2, feed was withheld from laying hens for 38 h and then the hens were force-fed diets containing 15% glucose, 15% CLA Source A, or 15% SO (two feedings of 30 g each). Excreta samples were collected for 36 h after the last feeding. The MEn values obtained for CLA Source A and SO were 8,517 and 8,437 kcal/kg, respectively. The MEn of CLA Source B (higher in unsaturated fatty acids than CLA Source A) was determined in Experiment 3 by feeding diets containing 4, 8, or 12% CLA Source B to 14-d-old chicks. Increases in dietary MEn with increments of CLA Source B were curvilinear, with resulting MEn of 9,375 to 9,588 kcal/kg of fat when CLA Source B was fed at 4 or 8% of the diet and 7,917 kcal/kg when fed at 12% of the diet. Results of this research show that CLA sources can contribute substantial energy to diets, but the MEn value of CLA sources for young chicks varies with fatty acid composition and dietary concentration.

Volatile profiles and lipid oxidation of irradiated cooked chicken meat from laying hens fed diets containing conjugated linoleic acid.

The objective of this study was to determine the influence of dietary conjugated linoleic acid (CLA) on lipid oxidation, volatile profiles, and sensory characteristics of irradiated cooked chicken meat. Forty-eight 27-wk-old White Leghorn hens were fed a diet containing 0, 1.25, 2.5, or 5.0% CLA. After 12 wk of feeding trial, hens were slaughtered, and boneless, skinless breast and thigh muscles were separated. Meats of three birds from a dietary treatment were pooled and ground together through a 9-mm and a 3-mm plate, and patties were prepared. Patties were individually packaged and cooked in a water bath at 85 C for 15 min. After cooling to room temperature, patties were repackaged in oxygen-permeable or oxygen-impermeable bags, irradiated at 0 or 3 kiloGray (kGy) with an electron beam irradiator, and analyzed for lipid oxidation, volatile profiles, and sensory characteristics at 0 and 5 d of storage at 4 C. Cooked meat patties from hens fed CLA diets had lower TBA-reactive substances values and produced less hexanal and pentanal than the control. The irradiated and nonirradiated cooked chicken meat with aerobic packaging developed severe lipid oxidation during the 5-d storage at 4 C. Irradiation accelerated lipid oxidation in aerobic-packaged cooked chicken meat, but its effect was not as significant as that of the packaging. No odor differences were found among the cooked chicken meats from the different dietary CLA treatments. The increased storage stability of cooked meat from hens fed CLA diets was caused by the increased saturated fatty acids and CLA content in meat lipids. Tissue CLA was stable from oxidative changes and had minimal effect on volatile production in irradiated and nonirradiated cooked chicken meat during storage.

Comparison of three techniques for internal jugular vein cannulation in infants.

Central venous cannulation allows accurate monitoring of right atrial pressure and infusion of drugs during the anaesthetic management of infants undergoing cardiopulmonary bypass. In this prospective, randomized study, we compared the success and speed of cannulation of the internal jugular vein in 45 infants weighing less than 10 kg using three modes of identification: auditory signals from internal ultrasound (SmartNeedle, SM), external ultrasound imaging (Imaging Method, IM) and the traditional palpation of the carotid pulsation and other landmarks (Landmarks Method, LM). The cannulation time, number of attempts with LM and SM techniques were greater than those with IM technique. The incidence of carotid artery puncture and the success rate were not significantly different among the three groups. In infants, a method based on visual ultrasound identification (IM) of the internal jugular vein is more precise and efficient than methods based on auditory (SM) and tactile perception (LM).

Effects of dietary potassium supplementation for growing turkeys on leg weakness, plasma potassium concentration, and selected blood variables.

The objectives of this research were to observe the effects of increased K in the diets of growing tom turkeys from 6 to 18 wk of age on body weight, feed-to-gain ratio, and leg weakness; to study the effects of time and temperature of blood storage after sampling and before centrifugation on plasma K concentration; and to evaluate plasma creatine kinase activity as an indicator of leg weakness. Male Nicholas White turkeys were fed corn-soybean meal based starter and grower diets from 1 d to 6 wk of age. At this time, each of three dietary treatments was assigned randomly to three pens of toms, 30 toms per pen. The dietary treatments consisted of 1) corn-soybean meal control (control) diets, 2) corn-soybean meal diets supplemented with 25% more K than the control diets contained (Mod K), and 3) corn-soybean meal diets supplemented with 50% more K than the control diets (High K). Potassium carbonate was used as the source of supplemental K for the Mod K and High K diets. Calculated K concentrations of the control diets fed from 6 to 9, 9 to 12, 12 to 15, and 15 to 18 wk were 0.84, 0.74, 0.57, and 0.54%, respectively. Results of laboratory analysis of the diets agreed closely with the calculated values. By 12 wk, toms fed the High K diets weighed less (P = 0.018) than toms fed the control diets, and this difference was still evident at 18 wk (P = 0.013), even though the High K groups were changed to the control diets at 12 wk. Toms fed the Mod K diets also tended to weigh less at 16 and 18 wk than those fed the control diets, however, the diet effect at the latter time was not significant (P > 0.05). There were no consistent effects of dietary K on feed efficiency. Total incidence of leg weakness at 12 wk was greater (P = 0.015) among toms fed Mod K and High K diets than for those toms fed the control diets. These results show that dietary K concentrations greater than those usually present in corn-soybean meal based diets for growing turkeys should be avoided. Increases in dietary K concentrations were associated with increases in plasma K concentration. Storage of blood after sampling and before centrifugation decreases the plasma concentration of K. The decrease is minimized when ambient temperature of storage is decreased. Accordingly, blood should be centrifuged immediately after sampling for accurate measurement of plasma K concentration. Plasma creatine kinase activity is not a good indicator of associated leg weakness unless physical activity and stress can be controlled before blood sampling.