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511.
Background:Previous research indicates that bahiagrass may be successfully conserved as baleage,but nutritive value is typically low for lactating dairy cows.The purpose of this study was to determine the effect of adding modest amounts of alfalfa forage(22%),achieved by inter-seeding alfalfa into an existing bahiagrass pasture,on baleage nutritive value and lactation performance of Holstein cows.Forage treatments employed were monoculture bahiagrass baleage(MBB;negative control),bahiagrass-alfalfa mixture baleage(BAB) and conventional corn silage(CCS;positive control).Thirty six mid lactation Holstein cows[34.8 ±5.8 kg 3.5%fat-corrected milk and 112 ± 19 d in milk(DIM)]were stratified according to milk yield and DIM and assigned randomly to 1 of 3 forage treatments.Cows were trained to Calan feeding gates and were offered a common CCS-based TMR in a 10-d covariance period followed by a 42-d treatment feeding period.Results:The BAB contained more protein and less NDF than MBB(12.6 vs 10.3%CP and 71.8 vs 76.6%NDF).Diet DMI was similar for MBB and BAB(19.5 vs 21.6 kg/hd/d),but cows consumed more of the CCS diet(25.5 kg/hd/d)than either baleage-based diet.Cows offered BAB tended to produce more milk than cows offered MBB based TMR(28.4 vs 26.1 kg/hd/d),but both baleage diets generated less milk than CCS-based diets(33.1 kg/hd/d).Milk cumpusition was similar across diets except for milk protein concentrations which were higher tor CCS than either MBB or BAB diets;however,milk urea nitrogen(MUN) was lowest for cows fed CCS diets.Cow BW gain was higher for BAB than MBB implying that a portion of the higher energy contributed by the alfalfa was being used to replenish weight on these mid lactation cows.Conclusions:Data from this study indicate that alfalfa inter-seeded in bahiagrass sod that produces BAB with as little as 22%alfalfa may improve nutritive value compared to monoculture bahiagrass baleage and marginally improve lactation performance of Holstein cows.Howev  相似文献   
512.
  1. This work constitutes the first comprehensive study of the epifaunal response to biological invasions in coralligenous habitats, which are one of the main hotspots of biodiversity in the Mediterranean.
  2. The epifaunal community inhabiting the invasive macroalga Rugulopteryx okamurae and other dominant sessile hosts on coralligenous habitats (i.e. the sponge Spongia lamella, the gorgonian Paramuricea clavata, and the macroalga Sphaerococcus coronopifolius) was characterized. A total of 137 taxa were found.
  3. There was a lack of functional equivalence between macroalgal species (both native and invasive) and sessile invertebrates. Despite the absence of significant differences in mean density values and number of species per replicate among host species, epifaunal composition on gorgonians and sponges differed significantly from that on both macroalgae.
  4. Epifaunal assemblages, especially those inhabiting macroalgal species, were dominated by generalist detritivorous species that can inhabit different hosts, while specialized interactions between mobile epifauna and sessile hosts were observed almost exclusively on sessile invertebrates. Moreover, epifaunal community associated with invertebrate hosts showed higher spatial heterogeneity in comparison with native and invasive macroalgae.
  5. A competitive displacement of native hosts by the spreading of R. okamurae on coralligenous habitats would likely result in a biotic impoverishment in terms of overall number of species and a taxonomical and functional homogenization of the epifaunal community. Specialist species with a heterogeneous distribution could be gradually replaced by a spatially homogeneous assemblage dominated by generalist species.
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513.
Growth performance of two Oreochromis niloticus strains, Chitralada and Red‐Stirling, their reciprocal crossbred and the Israeli tetra‐hybrid ND‐56 were assessed in net cages under on‐farming conditions. Throughout 268 days of grow‐out, the strains were weighed monthly and mortality, feed consumption and water quality were recorded. Ten rigid net cages (1.5 × 1.5 × 1.7 m) immersed in a 10 ha reservoir were linearly arranged near the reservoir outlet following a completely randomized design with two replicates for each treatment (strain). Each cage was stocked with 459 fish (120 fish m?3) and fed twice daily to apparent satiation with a commercial tilapia diet following the recommended feeding program. The final mean weights were higher for Chitralada (557.20 g) and the reciprocal crossbreds (522.95, 496.40 g) than those of Red‐Stirling (421.90 g). All treatments outperformed the ND‐56 tetra hybrid. Daily growth showed statistical differences between Chitralada (2.04 g) and Red‐Stirling (1.52 g) but they were statistically the same when compared with the reciprocal crossbreds (1.90, 1.80 g). The relative growth ratios showed the same trend observed in the results for daily growth. The mean survival rate was 98%. The overall growth rate showed that crossbred performed as well as the parental lines. All crossbred progeny presented red colouration with variable pattern of black marks corroborating the dominant inheritance of the red trait in Red‐Stirling strain.  相似文献   
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516.
The physiological measurements of collateral ligaments of distal interphalangeal joint (CL-DIPJ) differ in the literature. The factors that influence these differences are not well described. The aims of this study are to compare CL-DIPJ sizes in equines with different withers height, as well as to correlate body weight and hoof size to the size of these ligaments. In total, 52 horses were used in the study. They were divided into two groups according to wither height: Group 1 (G1) - 21 animals with up to 147 cm - and group 2 (G2) - 21 animals with greater than 148 cm. CL-DIPJ was ultrasonographically measured in order to find the mean of dorso-palmar (DPD) and latero-medial (LMD) diameters and the cross-sectional area (CSA). Hoof width and length were measured, and the results were used to calculate the hoof surface area. Withers height and body weight were also measured. Groups were statistically compared by Student's t test and Pearson's correlation application to each group. Groups were different in body size, HS and CL-DIPJ size when p < .05, except for the LMD of the medial collateral ligament of left thoracic limb. Withers height and body weight did not show significant correlations to CL-DIPJ size in G1, but they had little influence on the size of CL-DIPJ on G2. No correlation between the hoof size and the CL-DIPJ was noted in any of the two groups. In conclusion, the CL-DIPJ were larger in taller horses and their sizes were correlated to their height and weight, but they were not correlated to hoof size.  相似文献   
517.
ObjectiveTo evaluate the analgesic efficacy and safety of tumescent local anesthesia (TLA) in cats undergoing unilateral mastectomy.Study designProspective clinical trial.AnimalsA total of 12 ovariohysterectomized female cats.MethodsAll animals were premedicated with pethidine (4 mg kg–1) intramuscularly (IM), followed by induction of anesthesia with propofol (5 mg kg–1) intravenously and maintenance with isoflurane in oxygen. A refrigerated TLA solution (15 mL kg–1, 8 °C) was injected using a Klein cannula. The solution was composed of 0.5 mL of epinephrine (1 mg mL–1) and 40 mL of 2% lidocaine added to 210 mL lactated Ringer’s solution (final lidocaine concentration 0.32%). Heart and respiratory rates, systolic arterial blood pressure, temperature and oxygen saturation were measured during anesthesia. Blood samples were collected from the jugular vein for measurement of plasma lidocaine concentration using high performance liquid chromatography. Postoperative pain scores were evaluated hourly for 6 hours. Analgesic rescue was performed with tramadol (2 mg kg–1) IM and meloxicam (0.15 mg kg–1) subcutaneously.ResultsPlasma lidocaine concentration peaked at 90 minutes after injection of TLA, but no concentration considered toxic for the species was measured. The median postoperative analgesia time was 6 hours after injection of TLA.ConclusionsThis study found that TLA prevented sympathetic response to noxious stimuli during anesthesia and provided satisfactory postoperative analgesia in cats submitted to total unilateral mastectomy, with no apparent signs of toxicity.Clinical relevanceTLA can prevent sympathetic stimulation resulting from noxious stimuli during anesthesia, promoting good intraoperative conditions, proving to be a viable addition to analgesia in cats submitted to a total unilateral mastectomy.  相似文献   
518.
The aim of this study was to evaluate the occurrence of Shiga toxin (stx)-producing Escherichia coli (STEC) in diarrheic newborn calves, as well as the resistance profile of this microorganism against antimicrobials routinely used in veterinary therapy. The antimicrobial profile of Eugenia uniflora against E. coli clinical isolates was also analyzed. Specimens from the recto-anal junction mucosa were investigated by using chromogenic medium and identification of E. coli was done using microbiological methods (Gram staining, indole test, methyl red test, Voges-Proskauer test, citrate test, urease test, and hydrogen sulfide test). The stx1 and stx2 genes corresponding to the STEC pathotype were evaluated by using polymerase chain reaction and electrophoresis. The susceptibility profile to antimicrobial agents commonly used in veterinary therapeutic practice and the antimicrobial effect of lyophilized hydroalcoholic extract of E. uniflora L. leaves against E. coli clinical isolates were evaluated by disk diffusion and microdilution methods. Shiga toxin-positive E. coli was identified in 45% of diarrheic newborn calves (stx1 = 23.2%, stx2 = 4.0%, stx1 + stx2 = 18.2%). The frequency of stx-positive E. coli in the bacterial population was equal to 17.0% (168/990 clinical isolates): 97 (9.8%) stx1-positive E. coli, 12 (1.2%) stx2-positive E. coli, and 59 (6.0%) stx1 + stx2-positive E. coli isolates. All stx-positive E. coli analyzed showed resistance to multiple drugs, that is, from 4 to 10 antimicrobials per clinical isolate (streptomycin, tetracycline, cephalothin, ampicillin, sulfamethoxazole + trimethoprim, nitrofurantoin and nalidixic acid, ciprofloxacin, gentamicin, and chloramphenicol). Effective management measures should be implemented, including clinical and laboratory monitoring, in order to promote animal and worker health and welfare, prevent and control the spread of diseases, and ensure effective treatment of infectious diseases. The E. uniflora L. leaves showed inhibition of microbial growth based on the diameter of halos, ranging from 7.9 to 8.0 mm and 9.9 to 10.1 mm for concentrations of 50 and 150 mg/mL, respectively. This plant displayed bacteriostatic action and a minimum inhibitory concentration of 12.5 mg/mL for all clinical isolates. Its clinical or synergistic effects with antimicrobial agents must be determined from clinical and preclinical trials.  相似文献   
519.
Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.  相似文献   
520.
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