Average Standard Length Research Articles

Skeletal anomalies in gilthead seabream (Sparus aurata) larvae reared in different densities and water volumes

AbstractThis study describes the effects on the skeletal phenotype of two pivotal factors, density and water volume, don the hatchery (larval) phase of gilthead seabream (Sparus aurata) larvae previoulsy described for two model species (Danio rerio and Oryzias latipes) and sub‐adult (pre‐ongrowing) gilthead seabream (Sparus aurata). The experimental trial was conducted using single conditions in a pilot study, starting with a total of 615,385 eggs from the same batch. Three densities (LD low density: 25 larvae/L; MD medium density: 125 larvae/L; and HD high density: 250 larvae/L) and two water volumes (500 and 1000 L) were tested from spawning up to 60 days post‐hatching (dph) (average standard length: 1.79 cm; average dry weight: 27.11 mg). On the final samples, morphometric, anatomical, and histological data were collected for data pertinent to meristic counts and skeletal anomalies. The results (analyzed by means of multivariate analyses) indicated that the LD‐reared larvae were significantly longer and heavier than HD‐reared fish. Furthermore, LD‐reared gilthead seabream exhibited a significant reduction in the frequency of individuals with anomalies of jaws, vertebral body shape, and vertebral arches than the MD and HD conditions, which is in agreement with previous experiments carried out on model species and gilthead seabream sub‐adults.

Process Monitoring Using Truncated Gamma Distribution

The time-between-events idea is commonly used for monitoring high-quality processes. This study aims to monitor the increase and/or decrease in the process mean rapidly using a one-sided exponentially weighted moving average (EWMA) chart for the detection of upward or downward mean shifts using a truncated gamma distribution. The use of the truncation method helps to enhance and improve the sensitivity of the proposed chart. The performance of the proposed chart with known and estimated parameters is analyzed by using the run length properties, including the average run length (ARL) and standard deviation run length (SDRL), through extensive Monte Carlo simulation. The numerical results show that the proposed scheme is more sensitive than the existing ones. Finally, the chart is implemented in real-world situations to highlight the significance of the proposed chart.

Monitoring autocorrelated multivariate multiple linear profiles

AbstractIf the quality of a process can be represented by a functional relationship, a collection of this quality data is called a profile. In monitoring schemes, profile monitoring is used to evaluate the stability of a relationship. In some applications, quality data collected from continuous processes have time correlations and can thus be characterized by a linear relationship between more than one response and explanatory variables. Therefore, we investigate this type of multivariate multiple linear regression model with between‐profile correlations in this study. We propose two exponentially weighted moving average control charts for monitoring the regression parameters and the covariance matrix of the model. Our simulation results reveal that our proposed scheme has satisfactory performance in terms of the average run length and standard deviation run length criteria. Finally, we present an example using real data to demonstrate the applicability of the proposed scheme.

Generalized new exponentially weighted moving average control charts (NEWMA) for monitoring process dispersion

PurposeThis work aims to focuse on improving the performance of the new exponentially weighted moving average (NEWMA) scheme for monitoring process dispersion. The authors use the generalized time-varying fast initial response (GFIR) to further enhance the detection ability of variability NEWMA control charts at the process startup. The performance of the proposed chart and other schemes discussed in this article are evaluated; and compared using the average run length (ARL) and standard deviation run length (SDRL) measures. It is observed that the ARL of the proposed scheme is quicker in detecting small and moderate shifts in the process dispersion than its counterparts. The real-life application of the proposed scheme is presented.Design/methodology/approachThe dynamic parameter of GFIR is used to enhance the detection ability of variability NEWMA control charts. The authors apply GFIR to the control limit of variability NEWMA scheme. This further narrows the control limit, hence enabling it to swiftly detect small and moderate changes in process dispersion.FindingsThe authors present the performance comparisons by examining the ARL properties of the proposed chart and its counterparts. The performance comparison shows that the proposed chart is highly sensitive in detecting small and intermediate process shifts. The real-life application presented also supports the study’s conclusion from the simulation studies. The performance comparison of the proposed chart and its counterparts shows that the proposed scheme is efficient in detecting process abnormalities, especially at the startup.Originality/valueIn terms of the control limits, the proposed chart is the generalized variability NEWMA control chart in which all the previously proposed NEWMA variant schemes can be obtained. Also, the newly proposed control scheme is more efficient in detecting small or moderate persistent shifts in the process dispersion.

Enhanced fault detection models with real-life applications

<abstract> <p>Nonconforming events are rare in high-quality processes, and the time between events (TBE) may follow a skewed distribution, such as the gamma distribution. This study proposes one- and two-sided triple homogeneously weighted moving average charts for monitoring TBE data modeled by the gamma distribution. These charts are labeled as the THWMA TBE charts. Monte Carlo simulations are performed to approximate the run length distribution of the one- and two-sided THWMA TBE charts. The THWMA TBE charts are compared to competing charts like the DHWMA TBE, HWMA TBE, THWMA TBE, DEWMA TBE, and EWMA TBE charts at a single shift and over a range of shifts. For the single shift comparison, the average run length (ARL) and standard deviation run length (SDRL) measures are used, whereas the extra quadratic loss (EQL), relative average run length (RARL) and performance comparison index (PCI) measures are employed for a range of shifts comparison. The comparison reveals that the THWMA TBE charts outperform the competing charts at a single shift as well as at a certain range of shifts. Finally, two real-life data applications are presented to evaluate the applicability of the THWMA TBE charts in practical situations, one with boring machine failure data and the other with hospital stay time for traumatic brain injury patients.</p> </abstract>

Neutrosophic multivariate EWMA control chart

The MEWMA chart is one of the traditional multivariate charts which are widely employed in inspecting the quality of manufacturing and services. This chart is created through monitoring the small shifts of mean vectors of variable quality characteristics. Often in practice, the measurement of a quality characteristic produces uncertain, incomplete values, so that ambiguous numbers are obtained. In this condition, a neutrosophic-based control chart can overcome the problem resulting from the ambiguous data. The paper’s objective is to construct a new multivariate monitoring scheme based on a neutrosophic chart, namely the neutrosophic Multivariate EWMA (NMEWMA). Furthermore, the performance of the new multivariate monitoring scheme is evaluated in detecting process shifts employing the Average Run Length (ARL) and Standard Deviation Run Length (SDRL). This control chart is an innovation in the quality monitoring of uncertain data. The research result obtained indicates that the NMEWMA chart performs better than the MEWMA in finding the small mean shifts as well as in the real case application.

The Amazon sailfin catfish Pterygoplichthys disjunctivus x pardalis (Siluriformes: Loricariidae) in Panamá

Introduction: Despite having a rich and diverse native freshwater fish fauna, exotic species have been introduced to Panama since the 20th century. Objective: To report its presence in the fresh waters of Panama of a newly recorded exotic fish. Methods: Specimens were caught with gillnet in Gatun lake, on September 30, 2017. Results: Three specimens with average standard length and weight of 233mm and 307g, respectively, were identified as Pterygoplichthys disjunctivus x pardalis. This armored catfish, native to the Amazon basin, is breeding in Gatun and may threaten local species. Conclusion: The exotic fish Pterygoplichthys disjunctivus x pardalis has a reproductive population in Gatun Lake, Panama.

Histology of the digestive tract of the steno-endemic Cobitis herzegoviniensis (Teleostei: cobitidae) from Mostarsko blato (Neretva river basin, Bosnia and Herzegovina)

The study of endemic fish species is of great importance, considering that extensive knowledge is a prerequisite for adequate protection and conservation. This study investigated the histology of the digestive tract of the steno-endemic fish Cobitis herzegoviniensis Buj & Šanda 2014, from Mostarsko Blato (Neretva River basin, Bosnia and Herzegovina). Histology of the digestive tract of this species was investigated, since there is a scarcity of information regarding its digestive biology. Specimens (average total length 78 mm, average standard length 69 mm, mean weight 3,836 g) of the species C. herzegoviniensis were caught in the lower course of the Lištica River in the area of Mostarsko Blato in June 2019. The tissue of selected organs of the digestive system was used as the basic material. Using basic histological techniques, microscopic preparations were made from the tissue. This species has only esophagus and intestine. When studying the microscopic structure of the wall of the digestive tract, it was determined that the wall consists of three layers: mucosa (tunica mucosa), muscular layer (tunica muscularis) and outer layer (tunica serosa). The basic building block of the liver is the liver cell or hepatocyte.

Can the Sri Lankan endemic-endangered fish Labeo fisheri (Teleostei: Cyprinidae) adapt to a new habitat?

Labeo fisheri is an endemic and endangered freshwater fish of Sri Lanka. Mainly restricted to the upper reaches of the Mahaweli River basin, it has been previously reported living in deep rapids and among large rocks and boulders. An accidental record of a Labeo fisheri specimen from Victoria Reservoir led us to further study this habitat during the period from January to August 2017. This study was carried out to confirm the presence of a population of Labeo fisheri within the Victoria Reservoir and report its new habitat type in deep stagnant waters. We further investigated the food habits by analyzing the gut contents of L. fisheri in the Victoria Reservoir. Seven individuals were recorded from fishermen’s gill net catch in three fish landing sites along Victoria Reservoir, with an average total length of 24.80 ± 4.30 cm, average standard length of 19.70 ± 3.86 cm and average body weight of 197.69 ± 107.12 g. Based on gut content analysis, only phytoplankton, especially diatoms and cyanobacteria, were found in the gut of L. fisheri. This new population is facing the direct threat of fishing. Effective conservation measures are doubtful, since a fishery is well established in the Victoria Reservoir and the fishing gear used is not species-specific. More research is necessary to understand the population dynamics of L. fisheri in the Victoria Reservoir. In order to conserve it at this locality, community-based conservation measures are recommended.

PEMBERIAN PAKAN BUATAN DENGAN PERSENTASE YANG BERBEDA PADA PERTUMBUHAN IKAN NILA (OREOCHROMIS NILOTICUS LINN) MENGGUNAKAN HAPPA DI KOLAM KECAMATAN MARTAPURA KABUPATEN BANJAR KALIMANTAN SELATAN

Tilapia is a superior variety fish and is the result of crossing several tilapia varieties in several countries in the world. The purpose of this study was to determine the artificial feeding with different proportions on the growth of tilapia reared using happa in the pond. This research was conducted in Martapura sub-district, Banjar district for 2 months using happa. The test fish in this study had an average weight of 25-33 grams with a standard length of 8-10 cm. The maintenance area uses a pool equipped with 9 pieces of happa measuring 1m x1m x1m. The design method used RAL (Completely Randomized Design) with 3 treatments and 3 replications, namely treatment A (percentage of feed 7%), treatment B (percentage of feed 5%) and treatment C (percentage of feed 3%). Parameters observed included relative weight growth, relative standard length growth, condition factors, feed conversion, survival rate, mortality and water quality as supporting data. The results of the Liliefors normality test and the homogeneity of the Barlett variance showed that all data were normally distributed and homogeneous. The results of the analysis of Diversity (Anova) the growth of the average relative weight of individuals (A=409.69%, B=309.33%, C=259.99%), the relative growth of the average standard length of individuals (A= 73.32 ) %, B=50,98%, C=47,37%). Condition factor (A=4.73, B=4.94 and C 4.99), from the condition factor value, it can be said that the fish is fat (value >4). Conversion of food (A=2.30, B=1.90, C=1.18), water quality during rearing were generally still within the tolerance limits or general range so that they could support the life and growth of the test fish until the end of the rearing

Muscle pigmentation of Nile tilapia (<em>Oreochromis niloticus</em>) fed on crude palm oil incorporated fish feed

The effects of diets containing crude palm oil on muscle pigmentation and deposition of carotenoids in tilapia (Oreochromis niloticus) was studied. A total of 135 advanced fingerlings with an average body weight and standard length of 9.11±4.78 g and 8.1±0.8 cm, respectively were stocked in tanks for 8 weeks and fed with formulated diets containing crude palm oil (CPO) as the oil component. Weight, standard length, and carotenoid levels in fish were measured biweekly. Muscles of fish fed with the control diet and CPO incorporated diets had carotenoid levels of 0.14±0.03 µg/g and 0.28±0.01 µg/g, respectively. Skin of the fish had carotenoid levels of 3.24±0.02 µg/g in the control and 6.06±0.03 µg/g in the treatment. According to the results 3% CPO incorporated diet had a significant effect on enhancing flesh colour in tilapia. The sensory evaluation indicated that the flesh of CPO fed tilapia fillets were more attractive than the fillets of fish fed control diet. CPO oil is recommended as a natural food colourant for improving flesh quality of Nile tilapia fillets.

Growth performance, hematological responses and economic indexes of Colossoma macropomum (Cuvier, 1818) fed graded levels of glycerol

The aim of this study was to evaluate the performance, hematological responses and economic indicators of juvenile tambaqui Colossoma macropomum fed different levels of partial replacement of corn by glycerol (0%, 25%, 50%, 75%, and 100%). The experiment was conducted for 90 days in the production of aquatic organisms lab at the Nilton Lins University, Manaus, Brazil, in a completely randomized design, and consisted of four treatments, four repetitions and two sampling times. In total, 240 juveniles were used with initial average weight and standard length of 15.32 ± 1,61 g and 8.03 ± 0.22 cm, respectively. The fish were maintained in twenty 310 L water tanks that had a closed system with no reuse, continuous aeration, siphoning and replacement of water every 48 h. Feeding was twice a day with the experimental diets, which contained 28% crude protein. The following parameters were considered: zootechnical checks (weight gain + survival %), welfare (health) (hepatosomatic index + condition factor + viscerosomatic index), economic (Economic efficiency rate + economic profitability index) and hematology (hematology + metabolites + ions). The results of the study show that diets for juvenile tambaqui can contain up to 50% replacement of corn by glycerol without compromising the fishes' development under the conditions studied.

Phoretic association between Hisonotus chromodontus (Loricariidae: Hypoptopomatinae) and Ichthyocladius sp. (Diptera: Chironomidae) larvae in Amazonian streams

Abstract: Larvae of non-biting midges in the family Chironomidae can be found in association with several species of fish in the family Loricariidae. In this study, we describe the first record of phoretic interaction between larvae of Ichthyocladius sp. and the fish Hisonotus chromodontus in streams in the Amazon basin. Between July 2010 and March 2019, fish were collected from three streams of the Teles Pires River basin in the state of Mato Grosso, Brazil. We investigated the attachment site of chironomid larvae on the body of fish and the frequency of attachment. A total of 1.241 specimens of H. chromodontus were collected, among which nine hosts were found carrying in the ventral region a single Ichthyocladius sp. specimen. All Ichthyocladius sp. were attached to a spicule of fish between the pectoral and pelvic fins, in which they were observed at the fourth developmental stage at the beginning of the cocoon construction (1.50 mm). In addition, a pre-pupa larva (2.60 mm) and an empty cocoon (2.50 mm) were reported. The Loanda stream had the highest occurrence of this type of association (of 12 fish examined, three had larvae). The other two streams reported a lower occurrence: the Baixada Morena stream had three fish associated with larvae amongst 1105 fish examined, whereas the Selma stream had three out of 124 fish infested by larvae. The occurrence of only one larva per host can be related to the small body area of the host fish (average standard length = 26.60 mm and average weight = 0.31 g). We observed that the larvae prefer fixation sites in the vicinity of the pectoral and pelvic fin of the fish, which is presumably associated with the fact that chironomids feed on algae and debris suspended by the movement of loricariids. These streams differ with respect to the presence of riparian forests, which may affect resource availability and thereby influence ecological interactions between the species.

Monitoring multinomial processes based on a weighted chi-square control chart

Abstract: Interpreting an out-of-control signal is a crucial step in monitoring categorical processes. For the Chi-Square Control Chart (CSCC), an out-of control situation does not specify if it was a process deterioration or a process improvement. For this reason, a weighted chi-square statistical control chart WSCC is proposed with different weighting categories in order to enable an accelerated disclosure of a control situation after a shift due to a deterioration of quality and on the other hand, decelerate an out of control situation after a shift due to a quality improvement. Furthermore, in comparison with Marcucci’s method, the new procedure provides an accurate and easier way to interpret several signals. In other words, the WSCC allows a faster detection of an out-of control situation in the case of a quality deterioration, however, an out-of control situation is not quickly detected in the case of a quality improvement. Indeed, comparative studies have been performed to find the best control chart for each combination. Concluding remarks with comments and recommendations are given based on Average Run Length (ARL) and standard deviation run length (SDRL).

CUSUM control schemes for monitoring Wiener processes

Detecting the abnormal degradation rate of Wiener processes is important for quality control and reliability management. In this paper, we propose upper-side CUSUM control schemes for monitoring the abnormal degradation rate of three classes of Wiener processes. Average run length and standard deviation run length are applied to evaluating the efficiency of CUSUM control schemes. The results show that the proposed CUSUM control schemes can efficiently give out-of-control signals when the degradation rate of Wiener process accelerates. It is also shown that initial values of degradation rate and sampling frequency have significant influence on the performance of CUSUM control schemes.

Outliers Detection Models in Shewhart Control Charts; an Application in Photolithography: A Semiconductor Manufacturing Industry

Shewhart control charts with estimated control limits are widely used in practice. However, the estimated control limits are often affected by phase-I estimation errors. These estimation errors arise due to variation in the practitioner’s choice of sample size as well as the presence of outlying errors in phase-I. The unnecessary variation, due to outlying errors, disturbs the control limits implying a less efficient control chart in phase-II. In this study, we propose models based on Tukey and median absolute deviation outlier detectors for detecting the errors in phase-I. These two outlier detection models are as efficient and robust as they are distribution free. Using the Monte-Carlo simulation method, we study the estimation effect via the proposed outlier detection models on the Shewhart chart in the normal as well as non-normal environments. The performance evaluation is done through studying the run length properties namely average run length and standard deviation run length. The findings of the study show that the proposed design structures are more stable in the presence of outlier detectors and require less phase-I observation to stabilize the run-length properties. Finally, we implement the findings of the current study in the semiconductor manufacturing industry, where a real dataset is extracted from a photolithography process.

Reproductive biology of the Short-snouted Seahorse, Hippocampus hippocampus (Linnaeus, 1758) in the Eastern Black Sea of Turkey (Osteichthyes: Syngnathidae)

The reproductive characteristics of the Short-snouted Seahorse, Hippocampus hippocampus, was studied in the eastern Black Sea shore over a one-year period. Average standard length was 10.38 cm (6.15–13.3 cm) and weight 1.88 g (0.68–3.02 g). Males were slightly more common than females (females: 48%), but the difference was statistically insignificant (p>0.05). This was highest in autumn and lowest in winter, while there were no differences between the sexes (p>0.05). A sequential spiral of developing oocytes was observed from the earliest stage in the germinal ridge to the mature edge with the largest oocyte. Mature oocytes were found in histological sections during the summer season and the results obtained from gonadosomatic index values confirmed that the summer season is the breeding period of H. hippocampus at the eastern Black Sea shore of Turkey.

Natural anesthetics in the transport of Nile tilapia: Hematological and biochemical responses and residual concentration in the fillet

This study assessed the hematological and biochemical effects of natural anesthetics used in the transport of Nile tilapia (Oreochromis niloticus) and their residual concentration in the fish fillet. One hundred fish with an average weight of 816.36 ± 31.37 g and an average standard length of 31.27 ± 1.42 cm were distributed among five treatments: non-transported fish; fish transported in water only (control), fish transported in water + anesthetic vehicle (ethanol 36 μL L−1), fish transported in water + eugenol (20 μL L−1), and fish transported in water + Ocimum basilicum essential oil (20 μL L−1). The fish were transported in boxes (1.45 m long × 1.08 m wide × 1.03 m high, Trevisan®) for 2 h. Subsequently, hematological and biochemical parameters were evaluated. Meanwhile, fillet samples were removed to determine the level of residual deposition of those compounds in the fish muscle by gas chromatography–mass spectrometry (GC–MS). The fish transported with natural anesthetics showed a lower (p < .05) number of erythrocytes. Sedation with O. basilicum prevented alterations in energy metabolism, but did not prevent changes in the chloride and sodium electrolytes (p < .05). Glucose was higher (p < .05) in the fish from the eugenol group. The major components of O. basilicum essential oil were methyl chavicol (66.51%) and linalool (20.90%). The residual levels of the methyl chavicol and eugenol compounds in Nile tilapia fillets were 20.52 ± 2.05 and 75.04 ± 3.76 μg kg−1, respectively, which are below the acceptable levels of O. basilicum essential oil and eugenol for human consumption. Therefore, the natural anesthetics exhibited sedative capacity and did not cause harm, but induced alterations typical of physiological adjustments during transport stress.

Performance of robust EWMA control chart for variability process using non-normal data

The main purpose of quality control is to quickly detect the presence of assignable causes and shifts in the process so that an investigation of the process can be carry out as early as possible. The Shewhart control chart provides good performance when the observation data is normally distributed, whereas when the normality assumption is not met, a Robust control chart is needed. The performance of the control chart depends on the stability of the estimator used to estimate the process parameters and establish control limits in phase I. In this study, a Robust Exponentially Weighted Moving Average (EWMA) control chart will be present to monitor process variability using one of estimator Robust scale to estimate standard deviation. This estimator is used to develop robust control limits. Then evaluate the control chart performance using Average Run Length (ARL) and Standard Deviation Run Length (SDRL) with Monte Carlo simulation. Furthermore, the robust chart was applied to monitor the quality characteristics of the number of bacterial colonies in each aquaculture medicine product. The results obtained in this study are formed a control chart that is resistant to the existence of outliers and sensitive to shifts in the process of variability.

Plasticity of the skeleton and skeletal deformities in zebrafish (Danio rerio) linked to rearing density.

The teleost zebrafish (Danio rerio), an established model for human skeletal diseases, is reared under controlled conditions with defined parameters for temperature and photoperiod. Studies aimed at defining the proper rearing density have been performed with regard to behavioural and physiological stress response, sex ratio and reproduction. Studies concerning the effect of rearing density on the skeletal phenotype are lacking. This study analyses the response of the skeleton to different rearing densities and describes the skeletal deformities. Wild-type zebrafish were reared up to 30 dpf (days post-fertilization) in a common environment. From 30 to 90 dpf, animals were reared at three different densities: high density (HD), 32 fish l-1 ; medium density (MD), 8 fish l-1 and low density (LD), 2 fish l-1 . Animals at 30 and 90 dpf were collected and whole-mount stained with Alizarin red S to visualize mineralized tissues. The entire skeleton was analysed for meristic counts and 172 types of deformities. The results showed that the rearing density significantly influenced the specimens' average standard length, which decreased with the increase in the rearing density. Differences in meristic counts among the three groups were not observed. Rearing density-independent malformations affected the ribs, neural arches and the spines of the abdominal region, as well as vertebrae of the caudal complex. The HD group showed the highest number of deformities per specimen, the highest number of observed types of deformities and, together with the MD group, the highest frequency of specimens affected by severe deformities. In particular, the HD group showed deformities affecting arches, spines and vertebral centra in the caudal region of the vertebral column. This study provides evidence of an effect of the rearing density on the development of different skeletal phenotypes.