Generation of a Mixolab Profile After the Evaluation of the Functionality of Different Commercial Wheat Flours for Hot‐Press Tortilla Production

Refined wheat flours commercially produced by five different U.S. and Mexican wheat blends intended for tortilla production were tested for quality and then processed into tortillas through the hot‐press forming procedure. Tortilla‐making qualities of the flour samples were evaluated during dough handling, hot pressing, baking, and the first five days on the shelf at room temperature. The predominant variables that affected the flour tortilla performance were wet gluten content, alveograph W (220–303) and P/L (0.70–0.94) parameters, farinograph water absorption (57%) and stability (10.8–18.7 min), starch damage (5.43–6.71%), and size distribution curves (uniform particle distribution). Flours produced from a blend of Dark Northern Spring (80%) and Mexican Rayon (20%) wheat had the highest water absorption, and tortillas obtained from this blend showed the highest diameter and lowest thickness. The whitest and best textured tortillas were obtained from the flour milled from three hard types of Mexican wheat blend. A Mixolab profile was generated from the best tortilla flours, those produced by mills 3 and 4. The Mixolab profile showed that a good flour for hot‐press tortillas had a relatively lower absorption and short dough mix time compared with a bread flour and should have a significantly higher gluten compared with an all‐purpose flour. Compared with bread flour, the tortilla flour had higher retrogradation and viscosity values. The Mixolab profile proved to be a good preliminary test to evaluate flours for hot‐press tortillas.     

COLOR DOPPLER AND DOPPLER SPECTRAL ANALYSIS IN THE SPINAL CORD OF NORMAL DOGS

Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06.     

Investigation of Fresh and Freeze-Dried Seabream Spurus uurufu L. Eggs as a Fatty Acid Source in the Enrichment of Bruchionus sp.: Potential Use of a Waste Product

Abstract— Most marine fish larviculture is dependent on the culture and nutritional manipulation of live prey, of which the rotifers Brachionus sp. are one of the most commonly used. The particular reproductive characteristics of gilthead seabream Spus aurata L. lead to an egg overproduction in commercial hatcheries, where the excess is normally wasted. This study was developed with the objective of testing seabream eggs as an enrichment product for Brachionus sp., using as control the commercial product Algamac 2000×. In view of the need to preserve and store the eggs produced in excess, freezedrying was examined as a possible technical solution for this purpose. The fatty acid profiles of the tested enrichment products (fresh seabream eggs, freeze-dried eggs and Algamac 2000×), as well as of the enriched rotifers at 0 h and after 3,6,12, 15, 18 and 24 h of enrichment, were analyzed. Freeze-dried eggs were stored for 14 and 58 wk prior to analysis, in order to examine a potential deterioration of the fatty acid nutritional quality. A potential use of seabream eggs as an enrichment product for Brachionus sp. was demonstrated. Rotifers enriched with eggs, fresh and freeze-dried, presented relatively high levels of polyunsaturated fatty acids (PUFA), highly unsaturated fatty acids (HUFA; × C20 and 2 double bonds), and fatty acid methyl esters (FAME), a docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio of about 2 and a fairly high (n-3)/(n-6) ratio, especially during the first 3-6 h of enrichment. When freeze-dried eggs were stored in a dry atmosphere during 14 and 58 wk, only a slight and nonsignificant decrease was noted in the fatty acid content over this period of time. Therefore, freeze-drying may be an effective way of preserving the eggs in excess, at least up to 58 wk of storage.     

Crossability relationships between the common potato, Solanum tuberosum spp. tuberosum, and its wild diploid relatives S. kurtzianum and S. ruiz-lealii

The common potato, Solanum tuberosum spp. tuberosum (tbr), is a tetraploid species with a narrow genetic base, but with a large number of related species that harbor great genetic diversity for numerous characters of agronomic interest. S. kurtzianum (ktz) and S. ruiz-lealii (rzl) are wild diploid relatives with potential resistance to adverse biotic and abiotic factors. To evaluate if this wild germplasm can be incorporated by conventional crosses into the tbr gene pool, pollen-pistil compatibility relations and seed set in interspecific crosses with tbr were investigated. In 4x tbr × 2x ktz crosses and the reciprocals, 89% and 52.2% of genotypic combinations (respectively) were compatible at the pollen-pistil level. Seeds were obtained from some genotypic combinations in both directions of the cross, suggesting that functional 2n gametes might be produced by particular ktz genotypes. In 2x rzl × 4x tbr crosses and their reciprocals, 35% and 11.7% (respectively) of the genotypic combinations were compatible at the pollen-pistil level, but no seeds were obtained. These results indicate that the reproductive isolation between 4x tbr and 2x ktz is incomplete, and that gene exchange between them is feasible. Moreover, further studies will have to be carried out with rzl to ascertain its crossability with 4x tbr.     

Equine muscle fiber types: A histological and histochemical analysis of select thoroughbred yearlings

Equine skeletal muscle was histologically and histochemically analyzed in orderto measure fiber composition. Well-sampled open muscle biopsies were obtained from the semitendinosus muscle in select yearling Thoroughbreds. Each biopsy was sectioned and stained for the Harris Hematoxylin and Eosin and the modified Gomori Trichrome in order to demonstrate the basic muscle fiber morphology delineating intra and extracellular elements. A thirdstain, CA++ activated myosin Adenosine Triphosphatase at pH 9.4 was used to differentiate between specific types on the basis of enzyme activities. Subsequent differentiation of Type I slow twitch and Type II fast twitch muscle fibers was assessed on the basisof staining intensity. The high predominance of Type II fast twitch fibers ranged from 85.1 to 100 % with a mean of 90.5 %. Racing records, as two- and three-year-olds, were monitored in order to qualitatively compare histochemical results with performance achievements. While caution must be exercised, results of this investigation suggested that it may be possible, at an early age to partially predict the potential of each horse to adapt to training and to compete successfully in races of varying distances.     

3-Acetyl-4'-isovaleryl tylosin for prevention of swine dysentery

The 21 field isolates of Treponema hyodysenteriae which were tested were sensitive to 3-acetyl-4'-isovaleryl tylosin (AIV); the minimal inhibitory concentration was 0.25 to 16 micrograms/ml. 3-Acetyl-4'-isovaleryl tylosin administered prophylactically to pigs at concentrations of 5 to 100 mg/kg of feed and tylosin at 110 mg/kg of feed for 28 or 31 days prevented swine dysentery induced by tylosin-sensitive T hyodysenteriae strain SQ2; 15 nonmedicated, inoculated control pigs had bloody diarrhea, and 9 pigs died. In 2 additional trials, AIV administered prophylactically for 28 days at 55 or 110 mg/kg of feed prevented swine dysentery induced by tylosin-insensitive T hyodysenteriae strain B204. All of the inoculated principal pigs medicated with AIV at 55 or 110 mg/kg of feed or carbadox at 55 mg/kg of feed and the noninoculated sentinel pigs for each group had solid feces throughout the 56-day trial. In the nonmedicated, inoculated control groups, bloody diarrhea began at 4 to 5 days after inoculation was done, and 9 of 10 principal pigs and 6 of 9 sentinel pigs had dysentery; 2 pigs died. In the groups medicated with AIV at 27.5 or 5.5 mg/kg of feed, all 5 principal pigs and 3 or 4 sentinel pigs in each group had dysentery; 3 or 4 pigs in each group died. In the group medicated with tylosin at 110 mg/kg of feed, 7 of 10 principal pigs and all 9 sentinel pigs had dysentery; 1 pig died.(ABSTRACT TRUNCATED AT 250 WORDS)     

In vitro and in vivo production of cell wall degrading enzymes by Botrytis cinerea from tomato

The production and activity of pectolytic and cellulolytic enzymes byBotrytis cinerea in tomato plants, as well as by conidia of this fungus in some nutrient media was studied. In inoculated tomato plants, the activity of these enzymes varied. PME, endo-PG and exo-PG were produced in petioles and fruits, while cellulase was only found in those parts which were softened by the invading mycelium. PGTE could only be detected in the softened parts of the petiole stumps. In suitble substrates, PME, endo-PG and exo-PG are produced rapidly with the onset of germination of the conidia. At some temperatures, endo-PG activity was found before germination could be observed. Some endo- and exo-PG was detected in washing water of conidia. The significance of the production of these enzymes by germinating conidia in relation to the infection process on tomato plants is discussed.Samenvatting In geïnoculeerde delen van een tomateplant blijkt de activiteit van deze enzymen afhankelijk te zijn van de aard van het aangetaste weefsel en de mate van aantasting (Tabel 1). Conidiën blijken in bepaalde media zeer snel pectolytische enzymen te vormen (Tabel 2, Fig. 1). Endo-PG activiteit kon bij 26° en 30°C in een natriumpolypectaatmedium worden gemeten voordat kieming van de conidiën kon worden aangetoond, zij het in zeer geringe hoeveelheid, lijkt aanwezigheid van deze twee enzymen in niet gekiemde conidiën aannemelijk. PME blijkt in een pectinebevattend medium te kunnen worden aangetoond op het moment, waarop kiembuizen zichtbaar worden. Cellulase kon daarentegen in een medium met kiemende sporen niet worden gevonden.     

A critical path analysis of fruit production in strawberry

The method of Critical Path Analysis has been applied to strawberry fruit production from runner propagation to first harvest in an experimental situation. The quantitative components of yield and the stages of their creation have been identified and arranged in sequential order.Analysis of crop data showed that large variations in yield potential arose early in development, from causes not identified in the experiment. In the fruiting season there was a substantial shortfall in realisation of existing potential due to inefficient fertilisation of ovules and poor berry development.The analysis indicates three phases of development where factors not yet examined can have a large effect on yield.