Growth and maturation of three commercially important coral reef species from American Samoa

Fisheries Science - This study presents age-based life history information on three small-bodied species targeted in the American Samoan fishery: Chlorurus japanensis palecheek...     

Agronomic response and water productivity of almond trees under contrasted deficit irrigation regimes

We investigated the long-term effects of different deficit irrigation (DI) options on tree growth, shoot and leaf attributes, yield determinants and water productivity of almond trees (Prunus dulcis, cv. Marta) grown in a semiarid climate in SE Spain. Three partial root-zone drying (PRD) irrigation treatments encompassing a wide range of water restriction (30%, 50% and 70% of full crop requirements, ET_c) and a regulated deficit irrigation treatment (RDI, at 50% ET_c during kernel-filling) were compared over three consecutive growth seasons (2004–2006) to full irrigation (FI). The results showed that all deficit irrigation treatments have a negative impact on trunk growth parameters. The magnitude of the reduction in trunk growth rate was strongly correlated through a linear relationship with the annual volume of water applied (WA) per tree. Similarly, a significant relationship was found between WA and the increase in crown volume. In contrast, leaf-related attributes and some yield-related parameters (e.g., kernel fraction) were not significantly affected by the irrigation treatments. Except in PRD₇₀, individual kernel weight was significantly reduced in the deficit irrigated treatments. Kernel yield, expressed in percent of the maximum yield observed in the FI treatment, showed a linear decrease with decreasing WA and a slope of 0.43, which implies that a 1% decrease in water application would lead to a reduction of 0.43% in yield. Water productivity increased drastically with the reduction of water application, reaching 123% in the case of PRD₃₀. Overall, our results demonstrate the prevalence of direct and strong links between the intensity of the water restriction under PRD – i.e., the total water supply during the growing season – and the main parameters related to tree growth, yield and water productivity. Noteworthy, the treatments that received similar annual water volumes under contrasted deficit irrigation strategies (i.e., PRD₇₀ and RDI) presented a similar tree performance.     

Pathologic and immunocytochemical studies of morbillivirus infection in striped dolphins (Stenella coeruleoalba).

Hundreds of striped dolphins (Stenella coeruleoalba) died along the Spanish Mediterranean coast during the second half of 1990. We necropsied 58 dolphins. Partial collapse of the lungs with patchy atelectasis, subcutaneous edema, icterus, and stomatitis were the most prominent gross morphologic changes. Histologically, a bronchiolo-interstitial pneumonia was the most frequent lesion (72% of the animals). It was characterized by hyperplasia of alveolar epithelial type II cells and formation of multinucleate syncytia in alveolar and bronchiolar lumina. Other prominent lesions were encephalitis (69%), lymphoid depletion, and formation of multinucleate syncytia in the cortex of lymph nodes. The distribution of morbillivirus antigen was investigated in 23 well-preserved dolphins using a monoclonal antibody against the hemagglutinin glycoprotein of phocine distemper virus. Positive immunostaining was found in brain (77%), in lung (70%), and in mesenteric (61%), mediastinal (47%), and prescapular (45%) lymph nodes. Phocine distemper virus antigen was demonstrated less frequently in trachea, stomach, biliary epithelium, intestine, kidney, and mammary gland. Necrotizing-hemorrhagic pneumonia and encephalitis due to Aspergillus fumigatus were seen in three dolphins, whereas two animals had lesions of toxoplasmosis. Changes in our dolphins were similar to those caused by distemper in seals and porpoises. The origin of the dolphin virus and the relationships among dolphin, seal, and porpoise morbilli viruses are unknown.     

Floristic and structural recovery of a laurel forest community after clear-cutting: A 60 years chronosequence on La Palma (Canary Islands)

We analyzed a post-clearcut chronosequence (0.5 to 60 years after harvesting) in the laurel forest of La Palma island (Canarian Archipelago) to determine the recovery of the stands with respect to species composition, richness, life strategies and structural parameters of the canopy. Multivariate analysis showed that exotic species, as well as annual ruderal species were confined to early-successional stages, while native perennials, typical of laurel forests, dominated the late-successional stages. Total species richness decreased significantly with time after clear-cutting. The relative fast recovery of understory native species may be due to low forest floor disturbance during harvesting. Shade-intolerant pioneer, pioneer-remnant and shade-tolerant late-successional species were the main life strategies of native tree species. Most structural parameters showed a continuous and monotonic increase (basal area, biomass) or decrease (density, percentage of photosynthetic biomass) during succession. Once clear-cutting, here performed with an interval of 8 years, is abandoned, the recovery of the laurel forest seems possible due to careful logging that protects the soil and a rapid asexual regeneration of native tree species, revealing this to be a sustainable management practice.     

The application of polyamines by pressure or immersion as a tool to maintain functional properties in stored pomegranate arils

Pomegranate fruits were treated with putrescine (Put) or spermidine (Spd) at 1 mM either by pressure infiltration or by immersion and then were stored at 2 degrees C for 60 days. Samples were taken biweekly and were further stored 3 days at 20 degrees C for shelf life study. The treatments were effective on maintaining the concentration of ascorbic acid, total phenolic compounds, and total anthocyanins in arils at higher levels than in control samples. In addition, the two ways of polyamine application increased the levels of total antioxidant activity (TAA) during storage, especially when polyamines were applied by pressure infiltration. Moreover, Spd showed the best results on increasing TAA through maintenance of total phenolic compounds.     

The effects of contrasted deficit irrigation strategies on the fruit growth and kernel quality of mature almond trees

The aim of this study was to quantify and compare the effects of two different deficit irrigation (DI) strategies (regulated deficit irrigation, or RDI, and partial rootzone drying, PRD) on almond (Prunus dulcis (Mill.) D.A. Webb) fruit growth and quality. Five irrigation treatments, ranging from moderate to severe water restriction, were applied: (i) full irrigation (FI), irrigated to satisfy the maximum crop water requirements (ET_c); (ii) regulated deficit irrigation (RDI), receiving 50% of ET_c during the kernel-filling stage and at 100% ET_c throughout the remaining periods; and three PRD treatments – PRD₇₀, PRD₅₀ and PRD₃₀ – irrigated at 70%, 50% and 30% ET_c, respectively, during the whole growth season. The DI treatments did not affect the overall fruit growth pattern compared to the FI treatment, but they had a negative impact on the final kernel dry weight for the most stressed treatments. The allocation of water to the different components of the fruit, characterized by the fresh weight ratio of kernel to fruit, appeared to be the process most clearly affected by DI. Attributes of the kernel chemical composition (lipid, protein, sugar and organic acid contents) were not negatively affected by the intensity of water deprivation. Overall, our results indicated that PRD did not present a clear advantage (or disadvantage) over RDI with regard to almond fruit growth and quality.     

Cytological and bacteriological findings in guttural pouch lavages of clinically normal horses

Percutaneous washes of the guttural pouches were obtained from two groups of 15 clinically normal horses, one lightly exercised and the other heavily exercised. Microbiological and cytological studies showed a wide variation in the differential cell counts. The cytological pattern of the normal lavages (< 5 per cent neutrophils) was characterised by a large proportion of ciliated columnar epithelial cells, a few non-ciliated cuboidal epithelial cells, and less than 1 per cent monocytes, lymphocytes, and eosinophils. Abnormal lavages (with more than 5 per cent neutrophils) had higher levels of bacterial growth than normal lavages. There were significant differences between the bacterial growth and total cell count, and also between the neutrophil contents of the lavages from the two groups of horses.     

Filamentous forms of Bordetella avium: culture conditions and pathogenicity.

Difficulties in preparing suitable antigen for the microagglutination (MA) test led to the discovery of a filamentous form of Bordetella avium. Broth media high in nutrients, vigorous shaking, and incubation at 37 C appeared to promote the development of filamentous forms of the organism. Peptone broth did not induce the development of filamentous forms. Eleven different isolates having both smooth and rough colony types were tested and observed to form filaments of various lengths. Filamentous forms of B. avium hemagglutinated guinea pig erythrocytes were motile, had pili and flagella, and were stable up to the fourth or fifth passage in broth media, at which time a predominance of typical coccobacillus organisms were observed. Filamentous forms of B. avium originating from smooth-colony types were pathogenic in turkey poults, whereas the filamentous forms of B. avium originating from rough-colony types were not pathogenic.     

Immunocytochemical diagnosis of skin tumours of the dog with special reference to undifferentiated types

Immunoperoxidase techniques for S-100 protein, keratin, cytokeratin, vimentin and desmin were applied to 65 canine skin tumours. These included eight squamous cell carcinomas, eight fibrosarcomas, eight melanomas, eight mastocytomas, eight haemangiosarcomas, eight leiomyosarcomas, five liposarcomas and 12 poorly differentiated tumours. Consistent results were obtained within each group. Cytokeratin and keratin immunoreactivity was detected only in squamous cell carcinomas. Vimentin was present in fibrosarcomas, melanomas, haemangiosarcomas, mastocytomas, leiomyosarcomas and liposarcomas. S-100 protein immunoreactivity was detected in melanomas, haemangiosarcomas, liposarcomas and leiomyosarcomas. Only leiomyosarcomas were positive for desmin. According to these results the 12 anaplastic tumours were diagnosed either as carcinomas, fibrosarcomas or malignant melanomas.     

A direct plating method for monitoring the contamination of Listeria monocytogenes in silage.

Twenty-two silage samples were analyzed for the presence of L. monocytogenes using five Listeria selective plating media, with and without previous selective enrichment step. L. monocytogenes was recovered from 3 samples by both procedures, but direct plating allowed the quantification of Listeria population. Two of these positive samples were implicated in outbreaks of listeriosis in sheep; the L. monocytogenes population in these samples was about 10(6) cells/g. The L. monocytogenes population in the other positive sample was 10(3) cells/g. Direct isolation of L. monocytogenes was only possible from LPM, PALCAM and LSAMm media. MOX and LSM media were not selective enough to allow direct Listeria isolation. In our hands, LSAMm was the most suitable plating medium for the direct isolation and specific quantification of L. monocytogenes from silage employing a red blood cells overlay technique.