Distribution and structural variation of arabinoxylans in common wheat mill streams

In 19 wheat-milling fractions total pentosan content, calculated as 0.88 x (% L-arabinose + % D-xylose), varied between 1.44 and 30.66% on dry matter (dm). It increased with ash content once the latter exceeded 0.6% (dm basis). Water-extractable arabinoxylans were recovered by saturating water extracts to 65% ethanol. Their contents in the milling fractions varied between 0.35 and 1.38%, and above 0.6% ash content also increased with this parameter. Their L-arabinose-to-D-xylose ratios ranged between 0.65 and 0.39, with the lowest values found for the fractions with highest ash content, indicating that the ash-rich tissues contain more arabinoxylans that are less branched. (1)H NMR spectroscopy revealed that the decrease in L-arabinose-to-D-xylose ratio was accompanied by an increase in unsubstituted xylose residues and a decrease in disubstituted xylose residues, while the contents of monosubstituted xyloses were virtually constant.     

The effect of a seaweed concentrate on the in vitro growth and acclimatization of potato plantlets

Summary The seaweed concentrate ‘Kelpak’ is used commercially in the greenhouse and field to improve plant quality. ‘Kelpak’ was added to the in vitro culture medium of potato cv. ‘BP1’ and also applied as a leaf/soil drench immediately after transplanting. The addition of 0.25% seaweed concentrate to the medium improved plantlet quality and led to better establishment in the greenhouse. No beneficial effect of seaweed concentrate in the tissue culture medium was observed if a second cutting was part of the micropropagation process. Additional application of 0.5% seaweed concentrate in the greenhouse to plantlet cuttings derived from tissue culture was not beneficial.     

Assessment of chromium tripicolinate supplementation and dietary protein level on growth,carcass, and blood criteria in growing pigs

This study was conducted to evaluate potential interactive effects of supplemental Cr and dietary protein levels in growing pigs. Thirty-six individually penned barrows, 22 to 63 kg, were used in a 2 x 3 factorial arrangement of supplemental Cr (0 or 200 ppb from chromium tripicolinate) and protein level (76, 83, or 90% of lysine requirement). A corn-soybean meal basal diet was designed to supply all mineral and vitamin needs, 90% of the estimated metabolizable energy need, and 76% of the estimated protein need at 70% of ad libitum feed intake. Additional protein to 83 or 90% of the lysine requirement was provided by a soy protein isolate supplement. Growth data were collected for a 50-d period, and pigs were killed at a mean of 63 kg BW. Increasing lysine levels linearly (P < 0.01) increased ADG and liver weight. Lysine level had a quadratic effect on 10th rib backfat thickness (P < 0.05) and cooler shrink (P < 0.01) with the highest responses at the 83% lysine level. Increasing lysine level linearly decreased (P < 0.05) carcass content of ash and lipid and quadratically increased the carcass water content (P < 0.01). Carcass accretion rate showed a linear increase for protein (P < 0.01) and water accretion (P < 0.01). Dry matter composition of the longissimus muscle showed linear increases of ash (P < 0.05) and protein (P < 0.01) and a linear decrease of lipid content (P < 0.01) resulting in a linear increase (P < 0.05) of the protein to lipid ratio based on the increasing lysine levels. Pre-feeding insulin levels were increased (P < 0.05) with increasing level of lysine. One hour post-feeding, a quadratic lysine response for plasma glucose (P < 0.05) was observed with the lowest concentration at 83% lysine. Cr addition increased 10th rib backfat thickness (P < 0.10). There was no Cr x lysine level interaction (P > 0.10) observed for any of the growth or carcass traits. Plasma glucose concentrations pre-feeding were lower for Cr-supplemented pigs (P < 0.01). As expected, increasing protein levels in protein-deficient diets increased protein accretion while decreasing lipid accretion in 22 to 63 kg growing pigs; however, these effects were more clearly seen in the longissimus muscle than in the entire carcass. Supplementation of Cr exerted only minor effects with few Cr x lysine interactions observed in this study.     

Studies on the replacement policies in dairy cattle. III. Influence of variation in reproduction and production

The optimum policy of insemination and replacement of dairy cows was determined by the dynamic programming technique. The model used in the previous study was extended to allow variation in time of conception. From 2 to 7 months after calving three alternatives were considered for an open cow namely (a) inseminating the cow, with a calculated probability of success, (b) leaving her open, and (c) replacing her immediately. When it was profitable to leave a cow open, the optimum time for replacement during the lactation period was determined.The minimum production level for insemination to be the optimum choice depended on the stage of lactation and the parity of the cow. In the optimum situation the average calving interval was 371 days, while 13% of the cows had an interval of 14 months or longer.The optimum policy was greatly affected by changes in the replacement heifer price. Changes in the probability of conception and persistency of milk production had significant but smaller effects. In herds with a smaller decline in production after the peak, insemination should be continued for longer than in herds with a larger decline.The relation between production and calving interval that resulted from the optimum policy was determined. When a measure of milk production was used that was not affected by gestation, the average correlation was 0.09. The correlation increased to 0.35 when the total 305-day production was used.     

Infectivity virulence and immunogenicity of Anaplasma centrale live blood vaccine

Cross-bred Bos taurus calves, aged between 6 and 8 months, were inoculated with the Onderstepoort Anaplasma centrale live blood vaccine. One group of 15 calves were inoculated once only, while a 2nd group of 15 were revaccinated 6 months later. All the animals were challenged with approximately 1 X 10(10) Anaplasma marginale parasites of a known virulent strain 8 months after the first vaccination. The results of blood smear examination and the card agglutination test indicated that only 20 out of 30 animals vaccinated contracted A. centrale infections after the first attempt, and 3 out of 5 after the second. The vaccine conferred only partial immunity to challenge with a virulent A. marginale strain.     

Isolation and characterization of the heat stable enterotoxin from a pathogenic bovine strain of Escherichia coli

A heat-stable enterotoxin secreted by a pathogenic strain of Escherichia coli of calf origin was purified to homogeneity by a procedure involving acetone fractionation, DEAE cellulose chromatography, Biogel P2 chromatography and size exclusion high pressure liquid chromatography. The purity of the product was ascertained by amino-acid analyses and amino acid sequence using manual degradation with 4-N, N dimethylaminoazobenzene-4' isothiocyanate (DABITC) and an automatic gas phase sequenator. The following amino acid sequence is proposed: Asn-Thr-Phe-Tyr-Cys-Cys-Glu-Leu-Cys-Cys-Asn-Pro-Ala-Cys-Ala-Gly-Cys-Tyr. It is identical to a similar active peptide isolated from strains of porcine origin. Antibodies to ST were successfully produced in rabbits using a conjugate with bovine serum albumin. The ultraviolet absorption and circular dichroism spectra of the active product were recorded and discussed.     

Effects of diet formulations containing proteins from different sources on intestinal colonization by Campylobacter jejuni in broiler chickens

The objective of this study was to compare the effects of 3 diet formulations containing different protein sources (animal, plant, and a combination of animal and plant) on the colonization of Campylobacter jejuni in the gastrointestinal tract of broiler chickens. A freshly isolated strain of C. jejuni (biotype IV, serotype HS O:21, O:29, HL untypable) from a broiler chicken was used to infect 3-day-old chicks that had been free of C. jejuni; 0.5 mL of an inoculum containing 10⁸ colony-forming units was administered orally. Shedding of the organism was studied, and C. jejuni in the ceca, jejuni, and crop were enumerated by quantitative culture. The isolates recovered from the birds during the study period of 35 d were characterized and confirmed as C. jejuni by the use of standard methods and underwent biotyping, serotyping, antimicrobial susceptibility testing by disk diffusion and the E-test, and flagellin gene typing. A cyclical pattern of shedding of C. jejuni was observed in all the birds. Colonization was highest in the ceca. The ceca of birds receiving plant-protein-based feed had significantly less colonization then the ceca of birds receiving the other types of feed, whereas the differences in colonization of the jejuni and crops were not significant. Characterization by biotyping, serotyping, and flagellin gene typing showed that 95% of the recovered isolates were identical to the strain used for infecting the chicks. However, with the Lior-HL typing scheme, 74% of the recovered isolates were HL untypable. Antimicrobial resistance testing did not reveal significant differences between the infecting strain and the recovered isolates among the different feed groups.     

A Stenosis of the Isthmus Aortae Concurrent with Multiple Defects in a Calfheart An Attempt at an Embryological and Phylogenetical Explanation

The findings in a calfheart with multiple ventricular septum defects and an isthmus stenosis in an aorta with its origin in the right ventricle have been described and discussed. The anomalies are explained embryogenetically as well as phylogenetically. No choice could be made between the theories. The author states: The phylogenetic theory needs more attention in future comparative studies of anomalies of the heart.     

OSTEOCHONDROSIS LESIONS OF THE CANINE SHOULDER: CORRELATION OF POSITIVE CONTRAST ARTHROGRAPHY AND ARTHROSCOPY

In this study the correlation between positive contrast arthrography and arthroscopy was evaluated in a series of 20 shoulder joints (12 dogs) with radiographic and clinical evidence of osteochondrosis. The joints were consecutively examined by arthrography and arthroscopy. In 12 joints arthrography revealed the presence of a cartilage flap, and this finding was confirmed by arthroscopy. In 3 out of 8 joints where arthrography failed to demonstrate rupture of the cartilage, arthroscopy revealed the presence of a distinct fissure line. In 2 joints arthroscopy demonstrated a lesion comparable with chondromalacia and in 3 only a dimple in the articular cartilage was found. In 2 joints arthroscopy revealed the presence of small joint mice not detected by arthrography. Kissing lesions on the surface of the glenoid cavity opposite to cartilage flaps could be demonstrated as well. Evaluation of synovial inflammation, judged by the aspect and pattern of the synovial villi, correlated well with histologic findings. These results indicate that arthroscopy is a complementary examination in painful joints where arthrography fails to demonstrate rupture of the articular cartilage. It could be the procedure of choice if diagnostic and surgical arthroscopy can be combined. However, arthrography remains the technique of choice to demonstrate joint mice within the bicipital tendon sheath.     

Antibodies to immunoglobulin-G in dog sera, synovial fluids and aqueous humor: a comparative study of rheumatoid factor assays, suitable for routine application

The incidence of anti-IgG antibodies (rheumatoid factors, RF) in body fluids (sera, synovial fluids and aqueous humor) selected from 62 normal and 275 diseased dogs was studied. Fluids were assayed by canine versions of standard agglutinating and/or precipitating RF assays with routine application in human practice. The number of RF detected by dog IgG-coated particles was substantially higher by latex fixation test (LFT) than by modified Rose-Waaler (RW) test (61/144 vs. 14/144). This did not result from false positives by LFT since latex activity was completely inhibited by aggregated dog IgG. Some evidence is presented indicating that results obtained by standard RW in particular, but also those obtained by standard LFT, might be improved by modifying testing conditions currently used. Body fluids were further studied for the presence of precipitins to aggregated dog IgG in 0.6% agarose (gel precipitation test (GPT]. The frequency of RF was higher by GPT than by LFT, both in normal control fluids (for sera 26/52 vs. 19/52) and patient material (for sera 135/197 vs. 95/197). Thus, the canine RF appear to be a serum component with an unexpectedly high frequency in both normal and diseased dogs, but grossly underestimated by the recommended routine RF assays based on agglutination. The GPT, which combines a superior detection rate of theoretically also agglutinating RF with an inability to detect RF quantitatively, seems an ideal RF 'indicator' test to dictate improvements to the quantitative LFT/RW assays so as to facilitate RF detection at clinically relevant concentrations. Thus optimized, RW/LFT would provide the optimal detection apparatus for the ultimate isolation of the relevant 'RF' repertoire present, for comparative studies aimed ultimately at unraveling the etiopathogenesis of the 'real' RF.