QUANTIFICATION OF CEREBRAL VENTRICULAR VOLUME IN ENGLISH BULLDOGS

Quantitative measurement of cerebral ventricle volume of eight English bulldogs was performed using magnetic resonance (MR) imaging. The mean ventricular volume was 14.8 ml. with a range of 8.6 m1.-38.1 ml. The mean ventricular volume of two beagles was 2.2 ml with a range of 0.7 m1.3.7 ml. The percent of intracranial volume occupied by ventricle was found to be significantly larger in bulldogs (14.0%; S.D. = 7.9%) than in beagles (Range = 1.048%). The relationship between the percent of intracranial volume occupied by ventricle and measurements of body weight, age, sex, and various measures of skull anatomy of the bulldog was also determined. The relationship between ventricular volume and neurologic dysfunction was examined. There was a possible trend between high percent of intracranial volume occupied by ventricle and low body weight. This study will serve as a pilot study for examining the relationship between ventricular volume and neurologic disease in bulldogs.     

Toxicokinetics of the active doxorubicin metabolite, doxorubicinol, in sulphur-crested cockatoos (Cacatua galerita)

The pharmacokinetics of doxorubicinol, a cytotoxic metabolite of the anticancer drug, doxorubicin, were studied in four healthy sulphur-crested cockatoos (Cacatua galerita) after a 20 min intravenous infusion of 2 mg/kg. Plasma doxorubicinol concentrations were measured by HPLC. The pharmacokinetic parameters were estimated using a non-compartmental method. The mean (+/- SD) peak concentration was 8341 +/- 3132 microg/L at 17.5 +/- 5.0 min after the start of the infusion, and doxorubicinol concentrations declined biexponentially to 154.3 +/- 34.5 microg/L, 40 min after the end of the infusion. Systemic clearance was 0.940 +/- 0.473 L/h/kg, mean residence time was 0.165 +/- 0.133 h, and steady-state volume of distribution was 0.123 +/- 0.0526 L/kg. The terminal half-life was 0.660 +/- 0.611 h. Detectible but unquantifiable concentrations of doxorubicinol were present in the plasma ultrafiltrate of two birds during the infusion, indicating very extensive plasma protein binding. Physiological, haematological and biochemical monitoring over 3 weeks showed that doxorubicinol at a single infused dose of 2 mg/kg caused no toxicities of major concern.     

A Biophysical and Economic Assessment of a Community‐based Rehabilitated Gully in the Ethiopian Highlands

Gully erosion reduces agricultural productivity by destroying valuable land resources, increases sediment concentrations, reduces water quality, and fills up reservoirs. Gully rehabilitation has proven to be challenging especially in the high‐rainfall areas of the Ethiopian Highlands and has therefore had limited success. This paper describes a successful low‐cost gully rehabilitation effort with community participation in the Birr watershed in the Blue Nile basin that begun in early 2013. Initially, farmers were reluctant to participate for religious reasons, but with the aid of local priests and respected elders, community discussions, and a visit to a rehabilitated gully, a consensus was reached to rehabilitate a 0·71‐ha upland gully. The rehabilitation measures consisted of regrading the gully head at a 45° slope, constructing low‐cost check dams from locally available materials, and planting Pennisetum purpureum grass and Sesbania sesban. At the end of the first post‐implementation rainy season, 2,200 tons of soil was conserved by the constructed check dams and newly planted vegetation, compared with soil losses of 680 and 560 tons in two untreated, nearby gullies. In 2014, an additional 3,100 tons of soil was conserved. In 2013, the marginal rate of return (MRR) on the gully rehabilitation investment was 2·6 based on the value of increased forage production alone. When we include trapped soil nutrient values, the rehabilitation MRR was increased to 10. Although these numbers are impressive, the best proof of the success was that farmers on their own initiative rehabilitated an additional five gullies in 2014. Copyright © 2015 John Wiley & Sons, Ltd.     

A male-fertile Lycopersicon esculentum × Solanum lycopersicoides hybrid enables direct backcrossing to tomato at the diploid level

Solanum lycopersicoides Dun. is a wild nightshade native to Chile and Peru that possesses many traits of potential interest to tomato breeders, including environmental stress tolerance, resistances to disease and insect pests, and certain fruit quality characteristics. Sexual and somatic hybrids with the cultivated tomato (Lycopersicon esculentum Mill.) are readily obtained, yet have a strong tendency towards male-sterility combined with unilateral incompatibility, barriers that have deterred breeding efforts in the past. We report herein the synthesis of a partially male-fertile F₁ hybrid by sexual crosses between tomato and a recently collected population of S. lycopersicoides. Over 280 BC₁ plants were obtained by directed backcrossing to tomato at the diploid level, of which 58 were sufficiently fertile to permit selfing or additional backcrosses. The transmission of S. lycopersicoides genetic markers into a uniform L. esculentum background was confirmed with 24 isozyme or morphological loci on 11 of the 12 alien chromosomes. Potentially useful tolerance to gray mold (Botrytis cinerea) was demonstrated by inoculation of stem cuttings with mycelial plugs: at 6 days post-inoculation, the intergeneric hybrid showed little evidence of disease progression and the length of stem lesions averaged only one third that of susceptible controls. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of temperature, elevated carbon dioxide, and drought during seed development on the isoflavone content of dwarf soybean [Glycine max (L.) Merrill] grown in controlled environments

The effects of elevated temperature, carbon dioxide, and water stress on the isoflavone content of seed from a dwarf soybean line [Glycine max (L.) Merrill] were determined, using controlled environment chambers. Increasing the temperature from 18 degrees C during seed development to 23 degrees C decreased total isoflavone content by about 65%. A further 5 degrees C increase to 28 degrees C decreased the total isoflavone content by about 90%. Combining treatments at elevated temperature with elevated CO(2) (700 ppm) and water stress to determine the possible consequences of global climate change on soybean seed isoflavone content indicated that elevated CO(2) at elevated temperatures could partially reverse the effects of temperature on soybean seed isoflavone content. The addition of drought stress to plants grown at 23 degrees C and elevated CO(2) returned the total isoflavone levels to the control values obtained at 18 degrees C and 400 ppm CO(2). The promotive effects of drought and elevated CO(2) at 23 degrees C on the 6' '-O-malonygenistin and genistin levels were additive. The individual isoflavones often had different responses to the various growth conditions during seed maturation, modifying the proportions of the principal isoflavones. Therefore, subtle changes in certain environmental factors may change the isoflavone content of commercially grown soybean, altering the nutritional values of soy products.     

Editorial

Editorial

Editorial     

How does P affect photosynthesis and metabolite profiles of Eucalyptus globulus?

Phosphorus (P) has multiple effects on plant metabolism, but there are many unresolved questions especially for evergreen trees. For example, we do not know the general effects of P on metabolism, or if P affects photosynthesis via the internal conductance to CO(2) transfer from sub-stomatal cavities to chloroplast or amounts of Rubisco. This study investigates how P?deficiency affects seedlings of the evergreen tree Eucalyptus globulus grown for 2.5 months with four nutrient solutions differing in P concentration. To determine why photosynthesis was affected by P supply, Rubisco was quantified by capillary electrophoresis, internal conductance was quantified from gas exchange and carbon isotope discrimination, and biochemical parameters of photosynthesis were estimated from A/C(c) responses. Additional insights into the effect of P on metabolism were provided by gas chromatography-mass spectrometry (GC-MS) metabolite profiling. Larger concentrations of P in the nutrient solution led to significantly faster rates of photosynthesis. There was no evidence that stomatal or internal conductances contributed to the effect of P supply on photosynthesis. The increase in photosynthesis with P supply was correlated with V(cmax), and amounts of P, phosphate and fructose 6-phosphate (6-P). Phosphorous supply affected approximately one-third of the 90 aqueous metabolites quantified by GC-MS, but the effect size was generally smaller than reported for experiments on herbaceous species. Phosphorus deficiency decreased concentrations of phosphate, glucose 6-P and fructose 6-P more than it decreased photosynthesis, suggesting faster turnover of smaller pools of phosphate and phosphorylated intermediates. The effect of P supply on most amino acids was small, with the exception of arginine and glutamine, which increased dramatically under P deficiency. P deficiency had small or non-significant effects on carbohydrates and organic acids of the tricarboxylic acid (TCA) cycle. The small effect of P on carbohydrates, organic acids and (most) amino acids likely reflects a functional homeostasis among C metabolism (glycolysis, TCA and pentose P cycles), rates of photosynthesis and growth. The strong functional homeostasis in E. globulus may reflect a conservative, long-term growth and metabolic strategy of evergreen trees.     

Breeding bird response to partially harvested riparian management zones

We compared avian communities among three timber harvesting treatments in 45-m wide even-age riparian management zones (RMZs) placed between upland clearcuts and along one side of first- or second-order streams in northern Minnesota, USA. The RMZs had three treatments: (1) unharvested, (2) intermediate residual basal area (RBA) (targeted goal 11.5 m²/ha, realized 16.0 m²/ha), and (3) low RBA (targeted goal 5.7 m²/ha, realized 8.7 m²/ha). Surveys were conducted one year pre-harvest and three consecutive years post-harvest. There was no change in species richness, diversity, or total abundance associated with harvest but there were shifts in the types of birds within the community. In particular, White-throated Sparrows (Zonotrichia albicollis) and Chestnut-sided Warblers (Dendroica pensylvanica) increased while Ovenbirds (Seiurus aurocapilla) and Red-eyed Vireos (Vireo olivaceus) decreased. The decline of avian species associated with mature forest in the partially harvested treatments relative to controls indicates that maintaining an unharvested RMZ adjacent to an upland harvest may aid in maintaining avian species associated mature forest in Minnesota for at least three years post-harvest. However, our observations do not reflect reproductive success, which is an area for future research.