Histopathological findings in the early diagnosis of granulosa cell tumour in bitches

Granulosa cell tumour (GCT) is a majorly observed ovarian tumour in female dogs. It is essential to diagnose GCT in its initial phase before any symptoms occur, as histological and physiological differences may be observed based on the evolution of this neoplasia. This study aimed to analyse the anatomic histopathology of GCT in its initial stage, with findings of ovaries not yet with the suspicion of neoplasms in the Canis familiaris. A sample including 55 ovaries presented GCT in 40 female dogs. The histopathological analysis was performed considering the intensity of pleomorphism, vascularization and inflammatory infiltrate. Furthermore, we evaluated the mitoses count in 10 fields using 40× magnification. Out of the 40 animals evaluated, 62.5% (25/40) presented the tumour in only one ovary. The Call‐Exner corpuscle was present in 65% (26/40) of the cases. The follicular histological pattern was present in 52.5% (21/40) of the animals. The presence of the Call‐Exner bodies and the degree of tumour cell pleomorphism (p = 0.033) were associated. Moreover, the degree of vascularization and the intensity of the inflammatory infiltrate were also related (p = 0.001). In addition, there was a positive relationship between the increase in pleomorphism and the mean age of the animals (p = 0.044). This study confirmed that the appearance of this tumour may precede any clinical symptomatology. In this study, the most frequent histopathological pattern was the follicular. The characteristics of the granulosa cell tumour diagnosed early were poorly pleomorphic cells, low mitotic index and presence of Call‐Exner body.     

Genetic variability of rhizobacteria from wild populations of four Lupinus species based on PCR-RAPDs§

The metabolic capacities of rhizosphere bacteria can depend on intraspecific genetic variability at strain level. We sampled bacteria from the rhizosphere of three populations of four different Lupinus species at two growth stages (flowering: GS1 and fruiting: GS2). Isolates were identified to the genus level by classical biochemical tests. The most abundant genera found were Bacillus, Aureobacterium, Cellulomonas, Pseudomonas, and Arthrobacter. Genetic divergence of rhizobacteria was tested by PCR-RAPDs. The genetic distances were low, with mean values of 37 % for Bacillus, 25 % for Aureobacterium, 46 % for Cellulomonas, 16 % for Pseudomonas, and 23 % for Arthrobacter. Aureobacterium, the most abundant genus, predominated in the rhizosphere of all populations and at both growth stages (GS1 and GS2) of L. angustifolius. The Aureobacterium strains consisted of 11 groups with 90 % similarity indexes. The cluster analysis of these groups shows that strains isolated from different lupin species and sampling times have extraordinary low diversity indexes, or are even identical. This fact, together with the low genetic distance detected in the rhizosphere, reveals a clear specificity in the plant-bacteria interaction. This specificity could be related with several aspects of plant physiology.     

Survival of Post‐larval Litopenaeus vannamei Following Acclimation to Low Salinity Waters at Different Temperatures

Temperature and salinity are two factors known to influence the growth potential and survival of the Pacific white shrimp, Litopenaeus vannamei, acclimated to low salinity waters. In west Alabama, farmers suspect low water temperatures at stocking, in conjunction with low salinity and suboptimal ionic profiles, might be responsible for reduced survival and production at harvest. To determine the influence of temperature and salinity on post‐larval (PL) L. vannamei, a series of bioassays were conducted at the E.W. Shell Fisheries Research Station in Auburn, Alabama and Claude Peteet Mariculture Center in Gulf Shores, Alabama. PL L. vannamei of ages 11, 13, and 20 (PL₁₁, PL₁₃, and PL₂₀) were acclimated down to salinities of 12, 4, 2, 1, 0.5, and 0.2 ppt at different temperatures ranging from 17.6 to 24.0 C. During the acclimation bioassays survivals were assessed at 24 and 48 h. PL survival of the three age groups examined were significantly reduced at salinities of 1, 0.5, and 0.2 ppt. These results correspond well to those reported at higher temperatures confirming that across the tested temperature range salinity endpoint was the driving factor in determining survival and that suboptimal temperatures had a minimal influence on survival.     

Early stages of Margaritifera margaritifera glochidiosis in Atlantic salmon: Morphopathological characterization

Freshwater mussels of the order Unionida encyst into the fish mucosa to metamorphose and complete their life cycle, causing a parasitic disease known as glochidiosis. This parasitic stage represents a bottleneck for the survival of naiads, particularly for critically endangered species as Margaritifera margaritifera; however, little is known about the events occurring during this critical stage. Therefore, this study aimed to histologically characterize the development of M. margaritifera glochidiosis in Atlantic salmon to get insight into the pathogenesis of this interaction. Fish exposed to glochidia were sampled during the first 44 days post-exposure, and organs were observed by stereomicroscopy and light microscopy. Glochidia attached to the gills by pinching the lamellar epithelium, whereupon an acute proliferative branchitis engulfed most of the larvae. However, during the first 14 days, a severe detachment of unviable glochidia occurred, associated with the presence of pleomorphic inflammatory infiltrate and epithelial degeneration. In the cases where larvae remained attached, a chronification of the lesions with none to scarce inflammation was observed. These results provide key information to better understand the complex host–parasite interaction during the early stages of glochidiosis and provide valuable information to optimize artificial rearing of naiads in conservation of threatened freshwater mussel populations.     

Maguey (<Emphasis Type="Italic">Agave salmiana</Emphasis>) infructescence morphology and its relationship to yield components

Agaves are long-lived semelparous plants that produce a high number of seeds, in dehiscent capsules, on the apical section of a stalk, up to 5 m long, after 8–25 years. These and other characteristics such as yield and yield components are scarcely evaluated in the plants of the Agave genus. The objective of this study was to quantify the capsules and seeds yield of A. salmiana Otto ex Salm-Dyck plants simultaneously maturing and growing in the same region. Infructescences of three plants simultaneously growing at San Luis Potosí, Mexico, were harvested. On them we evaluated the number of umbels, capsules and seeds (normal and sterile) and their mass per plant. The study was developed on a completely randomized design with each infructescence as an experimental unit. Also, the type distribution of the number and mass of these yield components along the stalk was evaluated with the Chi square test for goodness of fit, the Shapiro–Wilks for normality tests, asymmetry and kurtosis. Data were analyzed with the ANOVA and multiple comparisons by the Tukey test (p?≤?0.05). The number of umbels per plant (17–25), capsule per umbel (2–179) and per plant (554–1990), normal seed per capsule (0–297), normal seeds per plant (30,610–186,209) and sterile seeds per plant (211,059–619,251) widely and significantly varied among infructescences. Biomass of capsules per plant umbel (3–795 g), biomass of sterile and normal seeds per capsule (0.071–1.449 and 0–3.320 g), per umbel (0.34–97.76 and 0.21–185.26 g) and per plant (182–1052 and 334–2069 g) also varied widely. Seed yield was statistically different between plants simultaneously growing and maturing at the same site.     

Loss of genetic variability in the captive stocks of tambaqui,Colossoma macropomum (Cuvier, 1818), at breeding centres in Brazil,and their divergence from wild populations

The loss of variability in farmed populations and the risks of interactions with wild populations support the need for the genetic monitoring of species farmed throughout the world. In Brazil, the tambaqui is the most widely farmed native fish species. Despite this, there are no data on the pedigree of the farmed stocks, and the potential for interactions with wild populations in the Amazon basin has raised concerns with regard to the genetic variability of these stocks. The present study analysed sequences of the mitochondrial Control Region and 12 microsatellites to characterize the genetic variability of seven historically important commercial tambaqui breeding centres located in four different regions of Brazil, and compared these sequences with those obtained from individuals collected from a wild population. High levels of genetic diversity were found in the wild population, whereas genetic diversity was reduced in both markers in most captive populations, except for the broodstock located near the Amazon River. High F_ST and D_EST indices were recorded between the wild population and most of the captive stocks analysed. The drastic reduction in genetic diversity found in most captive stocks and the difference between these stocks and the wild population may have been the result of the small size of the founding populations and the absence of breeding management. The renewal of the broodstocks and the application of breeding management techniques are recommended. In the Amazon region, in addition, the use of broodstocks that are genetically very different from local wild populations should be avoided.     

Effect of increasing docosahexaenoic acid content in weaning diets on survival,growth and skeletal anomalies of longfin yellowtail (Seriola rivoliana,Valenciennes 1833)

Five isoproteic (54.8%) and isolipidic (24.1%) microdiets, which varied in their docosahexaenoic acid (DHA) content (0.25%, 0.75%, 1.64%, 1.99% and 3.17%; dw), were manufactured to determine its effects on longfin yellowtail Seriola rivoliana larvae in terms of fish biological performance, whole body fatty acid profile and incidence of skeletal anomalies from 30 dah (11.31 ± 1.79 Total Length, TL) to 50 dah (19.80 ± 0.58 mm TL). The inclusion of dietary DHA up to 3.17% (dw) improved larval resistance to air exposure, although DHA did not significantly affect fish final growth or final survival. Indeed, high levels of dietary DHA (1.99% and 3.17%, dw) tended to increase the incidence of skeletal anomalies in S. rivoliana larvae, albeit no significant differences were observed. Furthermore, the occurrence of severe anomalies such as kyphosis and lordosis, was mainly associated to the larvae fed the highest levels of dietary DHA. In terms of survival, increasing dietary DHA levels did not significantly affect longfin yellowtail survival rate, despite a tendency for enhanced survival. The results of the present study proved that the inclusion of dietary DHA in inert diets up to a 3.17% (dw) and a DHA/EPA ratio above 3.1 increased the final survival and stress resistance in S. rivoliana larvae.     

Understanding the relationship between volunteers’ motivations and learning outcomes of Citizen Science in rice ecosystems in the Northern Philippines

This study relies on the Flying Beauties Citizen Science project conducted in the Philippines to assess personal motivations and learning outcomes of volunteers who were involved in documenting butterflies and dragonflies in rice ecosystems. While evaluation of motivations of volunteers in Citizen Science is not new, at least in affluent western countries, little is done in investigating volunteers’ motivations and learning outcomes of Citizen Science projects in low-income countries. Using surveys, we collected data from volunteers that were analysed qualitatively and quantitatively. We adopted a two stages evaluation format—before and after volunteers finished the project exercise. We compared pre-motivations to motivations attained and changes in level of knowledge before and after the project ended. We use Spearman’s Rho, Kendall’s Tau—nonparametric tests to draw correlations between variables. The results showed that key determinants that drove people to volunteer in the project were (a) learning about species and (b) being part of scientific research and the principal learning outcome was improved awareness about ecosystem functions of the species.