The amino acid profiles of the whole plant and of four plant residues from temperate and tropical forages

This study compared the amino acid (AA) profile of five residues (original forage, borate-phosphate buffer residue (BPR), neutral detergent fiber residue with (NDF+) and without (NDF-) sodium sulfite, and acid detergent fiber residue (ADF). Fourteen grasses and legumes from tropical and temperate regions were used in this study. The use of sodium sulfite did not affect the NDF concentration, but the NDF insoluble protein was lower (P < 0.05) in the NDF+ than in the NDF- (3.9 vs 4.5% DM, respectively). For all of the amino acids tested, the amino acid content, expressed as a percentage of CP, was lower in the ADF residue than in the original forage. There were no differences in the amino acid concentrations of the NDF- and NDF+ extracts (P > 0.05). Only in the case of methionine was there a difference in the amount of amino acid when the original forage was compared with the BPR (1.84 vs 1.45 % CP). When the AA profile of each residue was corrected for the AA content of the ADF, no difference was observed between the AA profile of the original forage and of the BPR (P > 0.05). Similar to the result without correction for the amino acids in ADF, the AA profiles of the NDF+ and NDF- fractions were similar (P > 0.05). From this result, we infer that the sodium sulfite had similar effects on all AA in the NDF residue that we tested. There were differences in amino acid concentrations in the original forage and the NDF residues for several amino acids (Met, Cys, Lys, Thr, Arg, Ile, Leu, and Phe) (P < 0.05). When the amino acid values of the original forage and the BPR were used with animal data in the Cornell Net Carbohydrate and Protein System model, few differences in animal predicted performance were evident. These findings suggest that the AA profile of the original forage can be used to predict the AA profile of the undegraded intake protein instead of using the borate-phosphate buffer residue for amino acid analyses. This would simplify obtaining feed amino acid values for use in the Cornell Net Carbohydrate and Protein System.     

核盘菌在亚麻上侵染致病的微观过程

 第1次利用电子显微镜对核盘菌在亚麻叶片上侵染致病的微观过程进行深入细致的观察。结果表明,该菌在侵入叶表面之前可能产生某些酶类物质来软化溶解亚麻叶表面角质层,以帮助该菌对叶表面的侵入。本文还对菌丝和子囊孢子侵染过程的异同进行了比较。     

Diversity of microbial products—discovery and application

Natural products derived from micro-organisms, plants and animals possess inherent biological properties and are, therefore, an excellent source of lead chemicals on which to base synthesis programmes employing rational design techniques. Only a fraction of the fungal kingdom has been screened systematically for novel metabolites despite their suspected potential. Moreover, the fungi are generally manipulable in laboratory culture systems and, because of their developmental versatility, they offer tremendous potential as sources of novel metabolites. Primary assay systems based on biochemical targets provide an effective means of screening microbial products; such assay systems also efficiently support chemical purification of lead activities and rapid elucidation of new chemical templates.     

Evaluation of toxicosis of liposome-encapsulated cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexane platinum (II) in clinically normal cats

OBJECTIVE: To determine adverse effects of single and multiple doses of liposome-encapsulated cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexane platinum (II) (L-NDDP) administered IV to healthy adult cats. ANIMALS: 10 healthy adult cats. PROCEDURE: 8 cats were given a single dose of L-NDDP (at rates of 75, 100, 150, or 200 mg/m2), and 2 cats were given liposomal lipid (1,500 mg/m2). Six of the 10 cats were given doses of L-NDDP at the maximum tolerated dosage (100 mg/m2) or a lower dosage (75 mg of L-NDDP/m2) at 21-day intervals, for a total of 4 treatments. Hematologic and serum biochemical analyses, urinalyses, and physical examinations were used to monitor effects of L-NDDP. RESULTS: All cats had transient pyrexia, lethargy, vomiting (1 to 3 times/24 h), inappetence, and an acute species-specific infusion reaction that was prevented by administration of atropine-diphenhydramine. Dose-limiting toxicosis was evident as a 10-day course of lethargy, intermittent vomiting, and diarrhea. In cats given multiple doses, dose-related thrombocytopenia, cumulative myelosuppression, transient increased hepatic transaminase activity, and mild to moderate hepatic hydropic degeneration and proximal renal tubular lipidosis in excess of lipidosis expected for this species were detected. Bone marrow hypoplasia was detected in some cats that received higher doses (cumulative dosages of 300 or 400 mg of L-NDDP/m2). CONCLUSION: Cats can safely be given L-NDDP at potentially therapeutic dosages without inducing renal or pulmonary toxicoses. CLINICAL RELEVANCE: Because L-NDDP has better tumoricidal activity than cisplatin (in vivo and in vitro) and is not cross resistant, it may be similarly or more efficacious than cisplatin in humans and dogs.     

Differences Between Cull and Normal Turkeys in Natural Infection with Mycoplasma meleagridis at One Day of Age

The thoracic air sacs of poults at one day of age were examined to compare those of normal, saleable poults with those of sibs culled¹ at hatching at three stages in the laying season. Lesions of airsacculitis were recorded and the air sacs were cultured for mycoplasma. Impression smears of the thoracic air sacs were stained with rabbit anti-Mycoplasma meleagridis serum conjugated with fluorescein isothiocyanate and examined to determine the location and infection rate of the organism. M. meleagridis were observed closely associated with or within epithelial cells of the air sac; within mononuclear cells and as extracellular “microcolonies”. The lesion and infection rate of cull poults in most hatches exceeded that of normal poults and infection with M. meleagridis was more often expressed (as a lesion) in cull than in normal poults.