Specific Growth Rate Research Articles

Preoperative Tumor Growth Rate Does Not Predict Overall or Progression-free Survival in Patients With Glioblastoma.

Presurgical tumor volume progression in glioblastoma (GBM) may be a predictor of survival. This study aims to evaluate the potential impact of preoperative tumor growth and other clinical as well as laboratory parameters on overall survival (OS) of GBM patients. We retrospectively analyzed 98 adult patients with GBM who received two magnetic resonance imaging (MRI) scans between 2013 and 2023, before primary surgery and concurrent Stupp chemoradiotherapy. Tumor growth rates were calculated to classify GBM into slower and faster growing categories. Statistical analyses, including Kaplan-Meier and multivariable Cox regression survival analyses, were performed to evaluate the impact of various clinical and treatment-related factors on OS and progression-free survival (PFS). Slower growing tumors had a significantly longer doubling time than faster growing lesions. Univariable analysis showed no significant differences in OS (p=0.12) or PFS (p=0.4) when analyzed according to tumor growth. When stratified by O6-methylguanin-DNA-methyltransferase (MGMT) status, there were still no differences in OS (p=0.14), but in PFS (p=0.009). In the multivariable Cox regression analysis, radiation dose (p=0.02) and the number of adjuvant cycles of temozolomide (TMZ) (p=0.002) were significantly associated with OS. MGMT status (p=0.02) and the number of adjuvant TMZ cycles (p<0.001) were significantly associated with prolonged PFS. Specific volume growth rate (SVGR), patient age, baseline tumor volume, Karnofsky performance status, extent of resection, and total radiation dose were not significantly associated with PFS. SVGR was not significantly associated with OS or PFS. In contrast, MGMT status, radiation dose, and number of adjuvant TMZ cycles were identified as predictors of treatment outcomes. These factors can guide physicians when designing personalized treatment concepts for patients with GBM.

Impacts of alfalfa nutrient concentrate on pellet physical attributes, growth performance, metabolism and nutritional quality of rainbow trout, Oncorhynchus mykiss

This study addresses the escalating demand for aquatic feed by exploring the potential of alfalfa nutrient concentrate (ANC) as feed ingredient for rainbow trout. Test diets contained varying ANC levels (0%, 5%, 10%, 15%, and 20%) to replace fishmeal (32% in the 0% ANC diet) to achieve equal digestible protein and were processed using a cooking extrusion method. Analysis of feed pellets showed that pellet density increased with ANC levels (P < 0.001), resulting in sinking pellets at 20% ANC. Water stability and durability were improved while oil leakage decreased with increasing ANC levels (P < 0.05). Two feeding trials were conducted to test the diets in flow-through water systems with three replicates per diet. The first 10-week trial evaluated their impact on feeding, fecal physical quality, and the apparent digestibility coefficient (ADC) of dietary nutrients in rainbow trout (initial body weight , 18.0 ± 0.2 g). ANC inclusion did not impact the palatability and satiety feed intake of the fish (P > 0.05). However, the ADC of dry matter and phosphorus significantly decreased in fish fed the 20% ANC diet (P < 0.05). The second 9-week trial investigated the growth performance, nutrition quality, and metabolism of rainbow trout (initial body weight, 19.0 ± 0.2 g). While all fish exhibited substantial growth, fish fed diets with 10% to 20% ANC displayed lower specific growth rate and higher feed conversion ratio compared to those fed with 0% or 5% ANC (P < 0.05). The whole body protein content was higher in fish fed 5% ANC compared to all other treatments (P = 0.030). The biochemical parameters of plasma were similar across treatments, except for a decrease in plasma phosphorus levels in fish fed a 10% ANC diet compared to those fed a 0% ANC diet. (P = 0.033). Significant changes were observed in liver metabolism including tricarboxylic acid cycle, amino acid and energy metabolism pathways in fish fed the 20% ANC diet versus the 0% ANC diet (P < 0.05). These results demonstrate that ANC inclusion improved pellet physical quality without impairing feeding behavior and nutritional quality of the fish but inclusion ≥10% in the diet reduced fish growth. This study offers the first comprehensive assessment of the potential of ANC used in fish feed involving feed management, feeding evaluation, and the biological response.

The impact of temperature on the growth of Pseudomonas aeruginosa in mineral waters originated from different wells: A predictive approach

This study aimed to evaluate the behavior of Pseudomonas aeruginosa (PSA) in natural mineral water sourced from three different extraction wells and stored at various temperatures (10, 12, 20, 23, and 30 °C) to calculate the kinetic growth parameters of this microorganism through predictive modeling. The physicochemical characterization of waters was also evaluated at the time of collection, and included the analysis of 40 different minerals, and quality parameters such as pH, conductivity, oxidation-reduction potential (ORP), total dissolved solids (TDS), salinity (PSU), and temperature (T). PSA survived in raw mineral water incubated at 12, 20, 23, and 30 °C; however, no growth was observed at 10 °C. Growth curves started with an initial population of ~ 2.5–3 log CFU/mL, and final PSA populations ranged from 3.5 to 4.9 log CFU/mL. The maximum specific growth rate (μmax) at 30 °C varied among the wells, with Well P-07 showing the highest growth rate (0.2 h−1), followed by Well P-08 (0.195 h−1) and well P-01 (0.133 h−1). At 12 °C, well P-01 exhibited the highest growth rate (μmax = 0.22 h−1), indicating a influence of mineral composition in the growth of PSA. The lag time (λ) also varied, with minimum values of 2.4 ± 0.1 h at 30 °C and maximum values of 41.6 ± 0.2 h at 12 °C. From these primary estimated parameters, it was possible to obtain five robust secondary models to describe the influence of temperature on the maximum growth rates and lag phase of PSA in the well. The estimated PSA growth parameters at 20 and 23 °C were subjected to a hierarchical cluster analysis and correlation plots to verify the influence of the physicochemical composition of the waters on the PSA behavior at each well's specific annual average temperature. This analysis confirmed a positive relationship (p < 0.05) between the presence of minerals (Ca, Fe, Sr, Mn, Na) and ions (SO4−3, Cl−) and the PSA lag phase time. These results underscore the need for tailored water quality management strategies that consider chemical composition and temperature to address specific microbial contamination risks.

Effects of soil physical ameliorants on the growth and root morphology of Prunus yedoensis and Ginkgo biloba seedlings in compacted soils

ABSTRACT Soil compaction is prevalent in forest ecosystems, it alters the physical structure of the soil and impedes tree growth. Although ameliorants are known to enhance soil properties and positively influence tree growth, studies remain limited on the effects of potential factors on root development in compacted soils after amelioration. This study aimed to examine the effects of the physical ameliorant treatments BIOC (compaction + biochar) and ORGF (compaction + organic fertilizer) on the soil properties, growth, and root development of Prunus yedoensis and Ginkgo biloba seedlings in compacted soils. We found that ameliorant treatments improved physicochemical soil conditions, such as bulk density, porosity, permeability, pH, total carbon, and total nitrogen, which in turn influence seedling growth. Specifically, in P. yedoensis, the relative growth rate of height was significantly higher in BIOC (46.19 ± 3.47%) compared to the control (29.58 ± 3.22%). The ameliorants did not significantly affect root morphological traits; however, we found that the total fine root length was positively correlated with shoot biomass in G. biloba (R = 0.97), but not in P. yedoensis. Root length tended to increase in BIOC, with measurements of 288.12 ± 68.97 m for P. yedoensis and 65.96 ± 25.08 m for G. biloba, while the mean fine root diameter tended to decrease in ORGF (1.25 ± 0.04 mm) and BIOC (1.37 ± 0.08 mm) for G. biloba. We conclude that biochar and organic fertilizer positively affect both soil properties and plant growth, highlighting that enhanced root development through ameliorants can improve plant growth in compacted soil.

Optimizing the combination of SiO2NPs and CeO2NPs on relative growth rate of Fragaria × ananassa plantlets cultured in vitro

Optimizing the combination of SiO2NPs and CeO2NPs on relative growth rate of Fragaria × ananassa plantlets cultured in vitro

A comparison of the early growth and survival of lesser-known tree species for climate change adaptation in Britain

Globally, climate change is altering both seasonal climates and the occurrence of extreme climate events, resulting in a drive to ensure our forests are resilient to these changes and the challenges they will bring. In Great Britain (GB), there has been a reliance on a limited number of species grown in monospecific plantations and concerns over the resilience of these forests is leading to a growing recognition of the need to diversify tree species composition. However, evidence of the relative growth rate and survival of alternative tree species and provenances during the critical establishment phase (typically within five or six years of planting) is often limited, hampering consideration of the wider adoption of many potentially suitable species. To address this knowledge gap, we compared tree height and survival data six years after planting from 34 provenances across 18 tree species at five experimental sites established across GB in 2012 in monospecific plots. For coniferous species, we found that Larix decidua, Larix x marschlinsii and Pinus radiata (on drier sites) were consistently amongst the tallest species, but survival could be variable. Pseudotsuga menziesii and Pinus pinaster also showed good early growth, matching the growth rate of Picea sitchensis (the most widely planted conifer in GB) when co-occurring and often exhibited good survival. In contrast Picea orientalis was slow to establish and amongst the smallest species at all five sites after six years, with Cedrus atlantica also performing poorly where planted. Surprisingly, we found very few differences in both mean tree height and survival between most provenances of the same species across all experimental sites, though more obvious differences may emerge as these trees mature. Only a small number of broadleaf species were available for analysis at age six in this study, but as expected Betula pendula generally performed well, while Acer macrophyllum often had very high mortality. While there are concerns around the susceptibility of pine species to Dothistroma septosporum and the future use of larch species in GB forestry is currently limited by the disease Phytophthora ramorum, our results highlight the potential for these species to establish well and exhibit good initial growth and survival on drier sites, with the same true of P. menziesii on moister sites. Future work should aim to understand whether further differences between species and provenances emerge with age and explore the potential of these emerging species as components of mixed-species stands to increase GB forest resilience to climate change.

Effect of Melia azedarach seed mediated nano-ZnO on growth performance, protein utilisation efficiency, haematology and nutritional status in pigs

The current study was conducted to investigate the effect of Melia azedarach seed-mediated ZnO nanoparticles on growth performance, protein utilisation efficiency, haematology and nutritional status in pigs. A total of 48 pigs were allocated to the following six treatments replicated 8 times: Negative Control (NC, No antibiotic), Treatment 2: Positive control (PC) given a conventional antibiotic (Oxytetracycline, 40 mg/kg feed); Treatment 3: Nano-ZnO 300 mg/L (N300ZnO), Treatment 4: Group given 150 mg/L Melia azedarach seed mediated nano-ZnO (N150MA), Treatment 5: Group given 300 mg/L Melia azedarach seed mediated nano-ZnO (N300MA), Treatment 6: Group given 450 mg/L Melia azedarach seed mediated nano-ZnO (N450MA). The experiment was conducted over 7 weeks. Melia azedarach seed-mediated ZnO nanoparticles had no significant effect on growth performance apart from average daily feed intake (ADFI) with treatment 3 having the highest value. It significantly affected protein consumption and growth efficiency but not protein efficiency ratio and specific growth rate. Melia azedarach seed-mediated ZnO nanoparticles had no significant impact on nutritional parameters, serum minerals apart from phosphorus which can negatively affect renal functioning.

Effects of Dietary Supplementation with Bacillus subtilis natto on Growth, Digestive Enzyme Activity, Immune Response, and Intestinal Microorganisms of Red Sea Bream, Pagrus major

This study investigated the influence of dietary supplementation with Bacillus subtilis natto (BSN) on various physiological parameters in red sea bream (Pagrus major). Key areas of focus included growth performance, enzymatic activity related to digestion, blood biochemical markers, immune function, and intestinal microorganisms. Fish were fed diets containing the following five levels of BSN: 0 (BN0), 1 × 107 (BN1), 1 × 108 (BN2), 1 × 109 (BN3), and 1 × 1010 (BN4) CFU kg−1 for 56 days. Fish in the BN3 and BN4 groups exhibited significantly enhanced growth performance compared to the BN0 group (p &lt; 0.05). Additionally, the activities of amylase and protease were markedly higher in the BN3 and BN4 groups (p &lt; 0.05), while lipase activity was significantly elevated in fish fed the BN3 diet (p &lt; 0.05). Plasma total protein levels also showed a significant increase in the BN3 group (p &lt; 0.05). Hematocrit values were significantly improved in the BN2, BN3, and BN4 groups (p &lt; 0.05). The intestinal microbiota of the BN4 group revealed a significant increase in the populations of B. subtilis and Lactobacillus, along with a notable decrease in Escherichia coli, compared to all other groups (p &lt; 0.05). The observed improvements in specific growth rate and the upregulation of growth-related gene expression further highlight the potential of BSN to enhance the growth performance of red sea bream. In conclusion, dietary supplementation with BSN at 1 × 109 and 1 × 1010 CFU kg−1 shows promise in improving the growth, health, and immune response of red sea bream.

Re-harvest application of 2-(3-chlorophenoxy) propionic acid on pineapple plants

The application of plant regulators such as exogenous auxin may provide effects on the translocation of carbohydrates to plant sinks, which may result in larger parthenocarpic fruits. The objective of the study was to evaluate the effects of the application of 2-(3-chlorophenoxy) propionic acid on the growth and quality of pineapple fruits. The experiment was carried out in a randomized block design. After floral induction, 2-(3-chlorophenoxy) propionic acid (CPA) was applied directly on the inflorescences at the following doses: 0 mg L-1; 40.0 mg L-1; 80.0 mg L-1; 120.0 mg L-1 and 160.0 mg L-1. Growth evaluations continued until 84 days after application, measuring fruit length (cm) with and without crown, crown length (cm), leaf D dry matter, fruit weight with and without crown (g), calculating if also, the absolute and relative growth rates. The post-harvest and quality characteristics of the fruits were also evaluated, as well as the harvest index. The application of CPA significantly reduces the length and weight of the crown of the fruits, however, the exogenous application of auxin provided an increase in the weight of the fruit. Regarding the post-harvest analysis, the application of CPA reduced the content of soluble solids in the fruit pulp.

Reduced canopy cover and development compromises weed suppression by buckwheat in cover crop mixtures

Buckwheat (Fagopyrum esculentum Moench) is a common cover crop typically grown for its rapid establishment and superior weed suppression. One challenge of incorporating buckwheat into crop rotations, however, is its short generation time, which requires in-season management to prevent viable seed production and volunteers in subsequent crops. Mixing buckwheat at reduced seeding rates with other cover crop species is one way for producers to reduce volunteer potential; however, this may compromise weed suppression. To investigate mechanisms behind buckwheat weed suppression and how using buckwheat in mixtures can affect suppression, we collected a series of morphological measurements in buckwheat monocultures and in three, two-way and four, three-way cover crop species mixtures and modeled their response over the growing season. We found that while buckwheat height and relative growth rate were unaffected with increasing species richness, there was a significant reduction in maximum leaf area index (3.75 vs. 2.85 vs. 2.82 cm2 cm-2) in mixture. Buckwheat monocultures provided superior season-long weed suppression compared to mixtures (85% vs. 53% vs. 50%). Principal component analysis showed that increased height and leaf area index values were associated with greater weed suppression. The link between reduced leaf area index and weed suppression in mixtures compared to buckwheat monocultures suggests that the rapid leaf development and canopy cover associated with buckwheat is a key mechanism behind weed suppression. In practice, producers should expect a dilution effect and weed suppression to be compromised when the buckwheat seeding rate is reduced in mixtures.

Exploring the Freshwater Cladocera (Pleuroxus spp.) as New Potential Live Feed in Aquaculture

In freshwater lakes, cladocera play a crucial role in the food chain, as they are the primary source of nutrition for nearly all aquatic species. Pleuroxus spp. are very suitable for aquaculture due to their ease of handling, rapid growth, non-selective filter feeder, high nutritional value, and remarkable ability to adapt to many environmental conditions. Silver barbs are in high demand in the aquaculture business due to their excellent flavours and rapid development rate. In this study, Pleuroxus spp. was cultured in a control condition with water quality maintained at the room temperature of 26 ± 1 °C and pH of 7.0 ± 0.5. Five treatments of Pleuroxus spp. were prepared, which comprised of T1 (control) = unfed, T2 = coffee grounds, T3 = corn flour, T4 = wheat flour, and T5 = sugarcane waste. Pleuroxus spp. were fed with a selected diet solutions at a concentration of 0.5 g/L daily. The result shows that Pleuroxus spp. given T3 (24.88 ± 5.48 ind/mL) had a greater population density than T4 (22.13 ± 4.83 ind/mL), T2 (21.06 ± 5.27 ind/mL), and T5 (20.56 ± 4.92 ind/mL) dietary treatments. Pleuroxus spp. given T3 had the greatest survival rate (97.9 ± 9.8%) when compared to other diets, T4 (86.81 ± 19.07%), T2 (82.71 ± 16.56%), and T5 (75.00 ± 21.08%). Silver barb showed the highest amount of daily weight gain in treatment T3 (0.11 ± 0.001 mg/days; p &lt; 0.05) compared with other dietary treatments. The maximum specific growth rate (SGR) (%) was achieved when fed with T3 (13.37 ± 0.02%; p &lt; 0.05). The feed conversion ratio (FCR) was shown to be significantly different (p &lt; 0.05). The FCR of larvae fed with different nutritional treatments ranged from 1.22 to 4.12, depending on the treatment. In comparison to other diets, the T3 treatment (1.22 ± 0.03) achieved the highest FCR ratio. In short, pre-feeding of zooplankton with prospective diets has built a baseline of improved aquaculture feeding procedures that may be employed in the future aquaculture businesses.

Metabolic engineering of Escherichia coli for the utilization of methylsuccinate, the product of methane activation via fumarate addition

Methylsuccinate is a branched-chain, 5-carbon (C5) dicarboxylate that can be generated from the O2-independent activation of methane via fumarate addition. However, no established metabolic pathway enables growth and product synthesis from methylsuccinate. Here, we report a synthetic pathway that converts methylsuccinate into two precursor metabolites: pyruvate and acetyl-CoA. The pathway was constructed through rational design and validated both in vitro and in vivo using E. coli as the host. Subsequently, growth on methylsuccinate as the sole carbon source was achieved using two parallel strategies: adaptive laboratory evolution and enzyme mining. Through the latter approach, we identified a heterologous electron transfer pathway mediated by previously uncharacterized enzymes and integrated into E. coli enabling the conversion of methylsuccinyl-CoA to mesaconyl-C4-CoA. The engineered strain demonstrated efficient growth on various C5 dicarboxylates including methylsuccinate, mesaconate, and itaconate, with a specific growth rate of 0.11 h−1 on methylsuccinate. This study represents an important step toward achieving synthetic methanotrophy, as the engineered strain can serve as a platform for screening potential methane activation enzymes and ultimately as a production chassis for the bioconversion of methane into various value-added products.

Growth and acclimation dynamics in reintroduced Erioderma pedicellatum (Hue) P.M.Jørg., a critically endangered cyanolichen in boreal rainforest

This study focuses on the critically endangered Erioderma pedicellatum, a sexually reproducing cyanolichen. The species’ decline is primarily attributed to habitat loss and extinction debts. The aim is to understand the possibilities of reintroduction via transplantation on Picea abies (L.) H.Karst. and gain insights into the species' growth response to environmental gradients in its boreal rainforest habitat. The source population of E. pedicellatum found on open, sun-exposed spruce branches within a waterfall spray zone, underwent a significant environmental shift when transplanted to the rainforest. The shift induced shade acclimation, which was marked by an increased maximal photosystem II efficiency (FV/FM), reduced thallus thickness and reduced apparent electron transport rate (ETRapp). However, stochastic fragmentation impacted 57 % of thalli, causing significant losses, particularly in sections with numerous apothecia, suggesting a trade-off between growth and reproduction. Unfragmented thalli with positive relative growth rate (RGR) exhibited increased growth correlated with base cation availability (high soil and bark pH) and light availability. Thalli that were already shade-adapted at the start (low ETRapp at high light) displayed the fastest growth in the rainforest. The best subset regression model of unfragmented thalli accounted for 72.8 % of the variation in RGR. The reintroduction of E. pedicellatum into the boreal rainforest is possible, but challenging, given that well-lit spruce branches with high base cation availability in humid canopy layers are rare.

Evaluating a Polyhouse Pond-based Aquaculture Production System for Cultivating Neolissochilus hexagonolepis (Chocolate Mahseer) in the Agro-climatic Conditions of Meghalaya, Northeast India

This study evaluated a polyhouse pond aquaculture system (PPAS, 200m2) for cultivating chocolate mahseer (Neolissochilus hexagonolepis) under Meghalaya’s agro-climatic conditions. Over two years, chocolate mahseer growth, survival, and biomass production in PPAS were compared against a conventional open pond aquaculture system (OPAS, 200m2). PPAS demonstrated substantial advantages, with fish exhibiting 34.6% higher final weight (112.24 ± 7.10g vs 83.38 ± 9.91g), 34.8% greater daily weight gain (0.31 ± 0.02 g/day vs 0.23 ± 0.03 g/day), 7.8% higher specific growth rate (1.10 ± 0.04 %/day vs 1.02 ± 0.08 %/day), and 16.1% better survival rate (83.85 ± 5.02% vs 72.20 ± 6.85%) compared to OPAS. Consequently, PPAS total fish biomass (941.97 ± 91.20 kg/ha) was 56.5% greater than OPAS (601.84 ± 90.60 kg/ha). PPAS maintained an average 2.4°C higher water temperature, with a 3.2°C difference during winter. Despite higher initial investment (₹ 85,000 vs ₹ 50,000) PPAS net profit (₹ 6,872) was substantially higher than OPAS (₹ 2,432) due to increased biomass. This innovative system mitigates environmental constraints, meriting further research for enhancing economic viability and long-term sustainability in adverse climatic regions.

Biomass Productivity and Photosynthetic Activity in Ulva compressa (Chlorophyta) in Raceway Photobioreactors Under Stress Conditions.

Research in seaweed cultivation technologies aims to increase production and reduce costs, leading to more efficient and sustainable processes. In this study, we analyzed the outdoor production of Ulva compressa cultured in summertime at different stocking densities of 0.6, 0.8 and 1.0 kg Fresh weight (FW) m-2 in a raceway photobioreactor with 30 m2 surface (3000 L), and its relation to photosynthetic activity. Under the experimental conditions of high temperature (>28-30 °C) and pH > 9 in culture water, higher seaweed density resulted in lower specific growth rate. The biomass production has been related to photosynthetic activity by using in vivo chlorophyll a fluorescence. Dynamic photoinhibition was observed at noon, which was less severe in cultures with higher algal densities. However, photosynthesis recovered in the afternoon. Seaweeds that were acclimatized for a week to the conditions of 1.0 kg FW m-2 stocking density showed an increase in biomass growth and absence of photoinhibition compared to non-acclimatized thalli. In conclusion, the cultivation of U. compressa in a mid-scale raceway photobiorreactor under conditions of high irradiance and temperature and low nutrient input, exhibited the best photosynthetic performance and hence the highest growth rates for the highest culture density assayed (1.0 kg FW m-2).

Identifying the gene responsible for non-photochemical quenching reversal in Phaeodactylum tricornutum.

Algae such as diatoms and haptophytes have distinct photosynthetic pigments from plants, including a novel set of carotenoids. This includes a primary xanthophyll cycle comprised of diadinoxanthin and its de-epoxidation product diatoxanthin that enables the switch between light harvesting and non-photochemical quenching (NPQ)-mediated dissipation of light energy. The enzyme responsible for the reversal of this cycle was previously unknown. Here, we identified zeaxanthin epoxidase 3 (ZEP3) from Phaeodactylum tricornutum as the candidate diatoxanthin epoxidase. Knocking out the ZEP3gene caused a loss of rapidly reversible NPQ following saturating light exposure. This correlated with the maintenance of high concentrations of diatoxanthin during recovery in low light. Xanthophyll cycling and NPQ relaxation were restored via complementation of the wild-type ZEP3 gene. The zep3 knockout strains showed reduced photosynthetic rates at higher light fluxes and reduced specific growth rate in variable light regimes, likely due to the mutant strains becoming locked in a light energy dissipation state. We were able to toggle the level of NPQ capacity in a time and dose dependent manner by placing the ZEP3 gene under the control of a β-estradiol inducible promoter. Identification of this gene provides a deeper understanding of the diversification of photosynthetic control in algae compared to plants and suggests a potential target to improve the productivity of industrial-scale cultures.

Multiple Paths to a Larger Mouth: Morphological Divergence in Two Island Populations of Australian Tiger Snakes (Notechis scutatus)

AbstractWe studied ontogenetic variation in skull morphology in tiger snakes sampled from mainland South Australia (Coffin Bay), mainland Western Australia (Herdsman Lake), Franklin Island, and Hopkins Island. The snakes from the two islands were selected because of their unusually large absolute body and head size, likely attained as a result of dietary constraints and strong selective pressure during thousands of years of isolation on islands. We performed geometric morphometric analysis of the skulls from these snakes to identify and precisely quantify morphological differences. Island snakes are born larger (trunk length) than mainland snakes, and consequently also tend to have larger absolute head size at birth. The heads of island snakes also show a faster relative growth rate (positive allometry) compared to those of mainland snakes, likely to cope with the large prey items found on these islands. However, the snakes from the two islands differ from each other in terms of morphological change associated with ontogeny, especially with regard to a palatal bone (ectopterygoid), which, compared to mainland snakes, is relatively longer in the snakes from Hopkins Island but shorter in the snakes from Franklin Island. Some morphological traits potentially associated with promoting a larger gape were also observed in one of the mainland populations (Herdsman Lake), consistent with standing variability for selection. Our results reveal that discernible changes in morphology and allometry in skull bones have evolved in island populations of tiger snakes in less than 10 000 years, and suggest that the large heads of island tiger snakes might develop via slightly different paths through morphospace on different islands.

Evaluation of the Dietary Arginine Supplementation on Yellow Catfish: From a Low-Temperature Farming Perspective

The yellow catfish is an economically significant freshwater fish with increasing importance in aquaculture. However, the low temperature environments prevalent in certain regions pose challenges to its growth, development, and overall health. This study aimed to explore the impact of dietary arginine (Arg) addition on the growth, digestive capacity, and intestinal antioxidant response in fish under low temperature acclimation (18 °C). Total 720 fish were randomly distributed into six groups, each containing 120 fish. Over the course of eight weeks, each group was fed with diets about varying Arg concentrations (1.79–3.26 g/kg). The results indicated that Arg supplementation resulted in an increase in specific growth rate (SGR), feed intake (FI), feed efficiency (FE), as well as pancreatic enzyme activities in both pancreas and intestine. Conversely, malondialdehyde (MDA) and protein carbonyl (PC) contents initially decreased but increased with higher Arg concentrations. Glutathione peroxidase 1a (GPX1a) showed a positive correlation with nuclear factor-erythroid 2-related factor-2 (Nrf2), showing its role in antioxidative capacity. Furthermore, this study revealed that Arg significantly enhanced the activities of anti-superoxide anion, anti-hydroxyl radical, and anti-oxidative enzymes, along with the relative mRNA abundance of Copper-Zinc superoxide dismutase (CuZnSOD), catalase, GPX1a, glutamate-cysteine ligase catalytic subunit (GCLC), and Nrf2 in the intestine. It was determined that yellow catfish weighing between 61.0 g and 89.0 g require an intake of 26.8 g of Arg per kilogram of diet based on polynomial regression analysis of specific growth rate (SGR), which is equivalent to 37.0 g of dietary protein, under sub-low temperature conditions of 18 °C.

The Growth Performance, Haematological Parameters and Serum Biochemistry of the Flathead Grey Mullet Mugil cephalus Under Recirculating Aquaculture System and Traditional Culture Systems.

The present investigation explored the growth performance, haematological parameters and serum biochemistry of flathead grey mullet under recirculating aquaculture system (RAS) and traditional culture systems. Nine hundred healthy fish, weighing 43.80 ± 3.55 g and length 16.54 ± 0.82 cm were randomly distributed to three treatments of RAS and traditional culture systems (T1: 20% of water changed daily; T2: once-through system 250 L/h; T3: RAS-20% of water changed weekly) in nine concrete tanks of 4000 L at stocking density of 100 fish/tank and each treatment had three replicates. Fish were fed (33.1% crude protein, 3 mm pellets) twice a day at a rate of 3% for 12 weeks. These findings suggest that the T3 followed by T2 led to notable improvements in growth performance compared to other culture systems. Significantly elevated values of weight gain, length gain, specific growth rate, average daily gain and survival % were observed in T3. The RBCs exhibited a significant decrease under T2. Haemoglobin concentrations and WBC counts significantly increased under RAS. Significant values of mean cell haemoglobin and mean cell haemoglobin concentration were recorded in T2. Total protein, albumin and globulin enhanced significantly under RAS, whereas the highest values of cortisol were observed in T2 and T3. These findings demonstrate that the RAS followed by once-through system significantly improve growth performance, feed efficiency and survival, as well as enhancing the haematology and serum biochemical status of flathead grey mullet. In conclusion, RAS provides ideal conditions for optimizing physiological functions, growth performance and fish health.

Characterization and pathogenicity of newly recorded Clonostachys rogersoniana against woolly apple aphid (Eriosoma lanigerum Hausmann) from India

BackgroundWoolly apple aphid (Eriosoma lanigerum Hausmann) (Homoptera: Aphididae) infests the aerial and edaphic portions of apple trees. It is responsible for the serious qualitative and quantitative reduction in apple fruits. This pest is mainly managed by chemical insecticides, so this present study was focused on the isolation of native entomopathogenic fungi (EPF), studying their growth characteristics and virulence against woolly apple aphids.ResultsClonostachys rogersoniana, as an EPF from an insect cadaver, was isolated and characterized, using morphological, microscopic, and molecular techniques. To the best of our knowledge, this is the first report of the occurrence of this fungus from India and it is named “C. rogersoniana isolate PUSACR01”. The radial growth and conidial yield of this isolate were excellent on PDAY among ten different culture media, whereas the relative growth rate and conidial germination were good on PDA and CA. The isolated fungus showed 85 and 86.67% mortality rates in adult females of the woolly apple aphid on day 11 at a concentration of 1.0 × 107 and 1.0 × 108 conidia ml−1, respectively. The LC50 values determined by probit regression analysis for days 7, 9, and 11 were 1.12 × 107, 2.52 × 106, and 4.74 × 105 conidia ml−1, respectively, while LT50 for concentrations of 1.0 × 105, 1.0 × 106, 1.0 × 107, and 1.0 × 108 conidia ml−1 were 18.73, 9.39, 6.71, and 5.03 days, respectively.ConclusionBased on the present study, C. rogersoniana would be considered a good biological control agent against the woolly apple aphid in apple orchards.