Khalid Abbas

• PhD
• Professor (Associate) at University of Agriculture Faisalabad

Exploited fish species are experiencing population decline and environmental changes due to human activities. As populations decline, genetic diversity may decrease, potentially resulting in a reduced ability to adapt to current and future ecological shifts. The prominent freshwater fish species, Wallago attu, faces extinction threats and has recen...

Over the past two decades, there has been a growing alarm about the role of unintended hybridization in shaping the current biodiversity. Major carps (Labeo rohita, Catla catla, and Cirrhina mrigala) are commercially important freshwater fish for aquaculture and are also found exclusively in the riverine ecosystems of Punjab, Pakistan. One of the m...

Genetic integrity of commercially important fish species is being compromised due to ongoing anthropogenic interventions. Hitherto, there are limited number of studies addressing the questions related to population structure of dwindling fish populations. Studies were undertaken to assess the genetic status of Bagarius bagarius populations from Ind...

The genetic integrity of fish populations has been continuously threatened due to various anthropogenic actions, particularly restocking programs. These losses in genetic diversity present erosion of global biodiversity. The genetic status of Hypophthalmichthys molitrix in the Indus River was assessed by using microsatellite markers. For the purpos...

Chlorpyrifos (CPF) is a widely used organophosphate pesticide which has an unfavorable impact on the aquatic ecosystem. This work was designed to compute the LC50 and lethal concentration (96-hr) of chlorpyrifos for Labeo rohita. The LC50 and lethal concentration (96-hr) of chlorpyrifos for Labeo rohita was determined as 10.39±0.03 and 15.31±0.05 μ...

DNA methylation-mediated transcriptional regulation has been considered to significantly impact some steroidogenic enzyme genes expression. To uncover the roles of DNA methylation on the regulation of aromatase gene expression during gametogenesis in Misgurnus anguillicaudatus, the expression profiles and cellular localization of cyp19a1a and cyp19...

Due to industrial advancement, a variety of toxic chemicals including metals are released into the aquatic environment which not only disturbs the physico-chemical properties of the water bodies but also influences the aquatic food chain to cause physiological and cytogenetic alternations in the aquatic animals. Metals have the ability to produce r...

The immense hydrological changes in the Yangtze River basin during the last decades have had drastic effects on the Yellowcheek Elopichthys bambusa migration rate and its population structure. As a consequence, the declining population size of the E. bambusa populations raises concern in terms of sustainability of their genetic integrity and conser...

Genetic diversity is considered to be necessary for the long-term survival of species as it enables environmental adaptations to increase a species' or population's chances of survival, but it is being threatened by several environmental changes and anthropological interventions. Five microsatellite markers were employed to analyze the genetic dive...

Authors' Contribution KA designed the idea and research layout. MJ conducted different experiments/laboratory work and wrote manuscript. SN, HA, TS and MSA assisted in experiments handling, results interpretation and technically monitor the experiments. SA and MAZ were members of supervisory committee and facilitated the author in conducting the re...

Cisplatin (CP), an effective chemotherapeutic drug, has been widely used to treat the several types of tumors. Orientin (ORI) is a flavonoid that shows versatile therapeutic activities. The current research was planned to observe the protective role ORI on CP induced renal injury in rats. Twenty-four male rats were divided into four groups equally...

The ability of populations to persist and adapt to environmental changes is based on genetic diversity. Substantial empirical data shows that the genetic integrity of natural fish population is being compromised by the effect of anthropogenic interventions and robust environmental conditions. Genetic diversity estimates were obtained for 210 indivi...

In this experiment, effect of lead (Pb) + chromium (Cr) mixture on superoxide dismutase (SOD) in the liver of Labeo rohita at a concentration of 11.1 mgL-1 was observed. The ammonium sulphate precipitation and ion exchange chromatography techniques were successfully used to purify SOD. After purification, SOD activity of control and Pb+Cr treated f...

The application of pesticides has been increased in agriculture to improve crop production all over the world. This may leads to existence of pesticides and their metabolites in freshwater bodies. Pesticides can trigger stress in organisms by increasing the number of reactive oxygen species. Oxidative stress biomarkers like antioxidants enzymes hav...

The widespread use of metals for industrial and non-agricultural purposes has resulted in the presence of their residues in various environmental matrices. Metal contamination of surface waters has been well documented worldwide and constitutes a major issue that gives rise to concerns at local, regional, national and global scales. Metals have gre...

In present work, a statistical model called linear regression was applied to find out the casual relation between the dependent variables oxidative stress dynamics viz. Superoxide dismutase (SOD), peroxidase (POx), catalase (CAT) and glutathion S-transferase (GST) and nuclear abnormalities (NAs) in Catla catla and one independent variable exposure...

Soil Arthropods are a vitally important component of the ecosystem, as their diversity, abundance, and distribution pattern play a vital role in ecosystem sustainability. Their population is expected to vary according to geographical patterns and environmental variables such as temperature, and humidity. For this purpose, we collected soil arthropo...

The purpose of this study was to isolate and characterize the disease causative bacterial species from commercially important freshwater fish species, Cirrhinus mrigala. For this purpose, diseased C. mrigala samples were collected both from cultured and wild conditions. From sampled fish, extracted gills, liver, intestine and skin were homogenized...

The current work was accomplished to purify the renal catalase (CAT) from carnivorous fish, Channa striata exposed to sub-lethal dose (1/3rdof LC50) of deltamethrin (DM)+endosulfan(END) mixture. Fish was kept under control and experimental conditions for 14-days. Water quality characteristics like temperature, total hardness and pH were kept stabil...

Glutathione S-transferase (GST) is vital in oxidative stress. Keeping in view the importance of this enzyme, present study was conducted for partial characterization of GST from hepatocytes of Cyprinus carpio. The inferences showed higher (GST) activity in liver of C. carpio collected from Chashma Barrage (144.33±1.15) as compared to Trimmu Head wo...

Glutathione S-transferase (GST) is vital in oxidative stress. Keeping in view the importance of this enzyme, present study was conducted for partial characterization of GST from hepatocytes of Cyprinus carpio. The inferences showed higher (GST) activity in liver of C. carpio collected from Chashma Barrage (144.33±1.15) as compared to Trimmu Head wo...

This work was performed to evaluate glutathione S-transferase (GST) activity and total protein contents (TPCs) in tissues viz. brain, gills, kidney, heart, muscle and liver of Labeo rohita kept under sub-lethal dose (4.13 μgL-1) of chlorpyrifos. Fish was kept under chlorpyrifos stress for two months and samples were collected on weekly basis. It wa...

Present study was conducted to assess the haematological profile of Channa marulius from hatchery and riverine populations. Blood samples were collected by caudal vein puncture. Significantly higher values (p ≤ 0.05) were recorded for various blood indices in hatchery populations as compared to those of riverine sources. Observed values of haematol...

The total protein contents (TPCs) in muscle of Labeo rohita, Catla catla and Cirrhinus mrigala collected from Jehlum, Ravi and Chenab was evaluated. Fish was sacrificed to obtained muscle and muscle homogenate was prepared for TPCs estimation. The lower TPCs were observed in River Ravi as 2.24±0.10, 2.35±0.15 and 3.42±0.15 for Cirrhinus mrigala, Ca...

The aim of this study was to assess the activity of peroxidase (Px) in relation to metal (Zn, Cr, Ni, Co and Cu) bioaccumulation in riverine Labeo rohita gills, liver, kidney and muscle tissues. The sampled fish organ tissues from River Indus-Pakistan's major fishing sites including Kalabagh (KB), Chashma Barrage (CB) and Taunsa Barrage (TB) were e...

The issue of male sexual dysfunction arises due to numerous complications linked with sperm motility, imbalance of antioxidant enzymes and hormonal levels. Carbon tetrachloride (CCl 4) is widely used as a standard toxin to induce chemical injury and toxicity. A lot of research has been performed on many species of the genus Nepeta in vitro and in v...

In an acute toxicity trail, LC50 and LC100value (96 hr) of endosulfan (END)+chlorpyrifos (CPF) mixture for Catla catla was computed. The genotoxicity of END+CPF mixture in RBCs of fish was also evaluated by comet assay. To check the genotoxicity of END+CPF mixture, blood of fish was sampled after 24-hr of intervals. Some fishes were also kept in cl...

From last few years contamination of aquatic bodies has been increased due to extensive use of pesticides in agriculture. The exposure of aquatic animals to these pesticides results in acute and chronic health effects. Fresh water fish species such as Channa striata serve as important bio-indicators for aquatic contamination to access the changes c...

In this study insecticides toxic effects of mixture of organochlorine (endosulfan) and organophosphate (chlorpyrifos) investigated on the activity of antioxidant enzymes viz. superoxide dismutase, peroxidase, catalase and glutathione S-transferase in different organs (liver, gills, kidney, brain, heart and muscle) of fish, Labeo rohita. The LC 50 o...

Toxic effect of lead (Pb)+chromium (Cr) mixture on superoxide dismutase (SOD) from kidney of Labeo rohita exposed to sub-lethal concentration for 14 days was evaluated. After purification, specific activity of enzyme was 1750.13 and 1272.72 U mg ⁻¹ in kidney of metal exposed and control fish, respectively. The enzyme from metal exposed kidney was 2...

The activity of digestive enzymes (Amylase and Lipase) is affected by the animal’s nutrition. Amylase catalyzes the hydrolysis of carbohydrates while lipase catalyzes the hydrolysis of ester bonds. The purpose of present study was to analyze the activity of above mentioned digestive enzymes in Labeo rohita under intensive culture system. Ten fish w...

The widespread use of chemicals like heavy metals and pesticides has resulted in the pollution of many aquatic habitats worldwide. Therefore, assessment of toxicity result from these chemicals is necessary to conserve the aquatic life in natural habitat. Present research was performed to calculate the 96-h LC50 and lethal concentrations of heavy me...

In aquatic bodies, heavy metals contamination is a most important issue all over the world. Heavy metals are persistence in nature and can store in aquatic environment. These metals have ability to induce oxidative stress and altered the enzymes activities. Therefore, in current investigation the activity of glutathione S-tranferase (GST) in hepati...

The patterns of genetic variability and genetic differentiation among five wild and five hatchery populations of Catla catla were assessed using 15 microsatellite markers in a total of 500 individuals (50 individuals per population). In both wild and hatchery populations of C. catla, the level of genetic diversity was observed low-to-moderate in te...

This research work was performed to evaluate the glutathione S-transferase activity and total protein contents in liver of carnivorous fish, Wallago attu exposed to sub-lethal concentrations (1/3rd, 1/4th and 1/5th) of cadmium for14days. Fish was sampled after 7 days interval. Spectrophotometric method was used to analyze the GST activity and prote...

The freshwater ecosystems are extensively polluted with heavy metals discharged from industrial, domestic, and other human activities. These metals are significant stimulators of oxidative stress in aquatic organisms, especially fish, leading to the creation of reactive oxygen species. Therefore, current research was conducted to elucidate the toxi...

In this research work Superoxide dismutase (SOD) enzyme from the kidney of silver carp (Hypophthalmichthys molitrix) was studied. Fish was divided into two groups. One group kept under chronic exposure of metals mixture (Pb+Cr) for 15 days and other group of fish was kept under controlled conditions. Partial purification of SOD was done by Ammonium...

Three major carps namely; Labeo rohita, Catla catla, Cirrhinus mrigala are commercially important aquaculture freshwater fish species of Pakistan. Ascertaining the pure species status of major carps is essential for their appropriate management and conservation. The use of microsatellites DNA markers and Bayesian models based statistical methods ha...

The genetic integrity of the commercially important fish species is being compromised mainly due to artificial propagation. The present study evaluated the extent of genetic variability and assessed the population structure of Silver Carp (Hypophthalmicthys molitrix) in hatchery stocks of Punjab province, Pakistan using 16 species-specific microsat...

Genetic integrity of distinct local fish populations is being compromised in face of growing anthropogenic interventions and environmental degradation. The present study examined the genetic structure of Rohu, Labeo rohita in riverine populations of Punjab, Pakistan, as influenced by anthropogenic interventions. Average 25 fish specimens were colle...

The current study was conducted to determine the tolerance limits of Indian major carps viz. Catla catla, Cirrhina mrigala and Labeo rohita against pesticides mixture (Bifenthrin + Chlorpyrifos + Endosulfan) and to see it effect on antioxidant enzyme like superoxide dismutase (SOD) activity in the liver of these species. The 96-hr LC50 and lethal c...

The fish fauna in the Yangtze-based riparian ecosystem has been imperiled largely due to genetic degradation of populations. Regular genetic monitoring of the fish populations is required for an effective management and conservation. The genetic structure of Dojo loach, Misgurnus anguillicaudatus was investigated in twelve populations originating f...

In the present study, kidney tissues were selected to measure the catalase (CAT) enzyme activity due to their responsibility in the elimination of the compounds generating reactive oxygen species (ROS). Variation in Oreochromis niloticus kidney CAT activity (114.33±0.33 to 159.5±0.03) was observed throughout the study period. During first week of e...

The activity of digestive enzymes was determined in Hypophthalmichthys molitrix, Catla catla and Cyprinus carpio fed with different feed ingredients. There were two glass aquaria (3×2×2 ft) for each species and ten fish in each aquarium. Fish in one aquarium were fed on rice polish and fish in second aquarium were fed on corn gluten @ 3 % of their...

Genetic diversity and structure of six Populations of Wallago attu were studied from Jhelum River, Pakistan using five species specific microsatellite loci. Genotypic data of all the samples were generated through PCR amplification of targeted loci. A total of 23 alleles were found in 177 fish samples. All the microsatellite loci were found to be p...

Water contamination is a severe environmental issue and has worse effects on fish health. Antioxidant system is present in all living organisms that maintain redox homeostasis by neutralizing reactive oxygen species (ROS). Catalase (CAT) is the part of antioxidant system that protect an organism from oxidative stress by detoxifying H2O2 into H2O an...

The current study investigated abundance, species richness and diversity of Ichthyofauna of hill torrents of Suleman Mountain, Range, Dera Ghazi Khan Region, Pakistan. Fish sampling was carried out from ten sites. The fishes were identified following standard taxonomic keys. Relative abundance (%) and diversity indices were calculated. One way anal...

Acute toxicity tests (96-hr LC50 and lethal concentration) of chromium (Cr) and cadmium (Cd) were conducted with two fish species viz. Channa marulius and Wallago attu. At the end of each trial, the fish were dissected and their organs viz. gills, kidney and liver were isolated for the determination of antioxidant enzymes activity. Cadmium was sign...

The genetic structure of Labeo rohita in hatchery stocks of the province Punjab was assessed by using five species-specific microsatellite markers. The samples of L. rohita were collected from six selected hatcheries. The genotypic data of each sample was generated through PCR amplification of target loci and allelic scoring by gel electrophoresis....

Heavy metals are common aquatic pollutants and their importance is increasing due to anthropogenic activities. These pollutants reduce fish metabolic rate and hence reduce their growth. Heavy metals produce reactive oxygen species which cause oxidative stress. The fish, Cirrhina mrigala was given the sub-lethal concentrations of copper and cadmium...

The purpose of present study was to analyze and compare the nutritional values of wild captured and farm cultured Cirrhinus mrigala. The proximate composition of fish meat, head, scales, fins and skin were examined in this study. From both sources (wild and farm), 42 fish specimens were collected and divided into three different weight categories i...

In the present study, kidney tissues were selected to measure the catalase (CAT) enzyme activity due to its responsibility in the elimination of the compounds generating reactive oxygen species (ROS). Variations in Oreochromis niloticus kidney CAT enzyme activity (114.33±0.33 to 159.5±0.03) were measured throughout this study period. During first w...

A screening of ploidy level in 2146 individuals from 52 populations of the loach Misgurnus anguillicaudatus in China was performed. Ploidy level variation and its geographical distribution in this study was combined with previously reported data from another 28 populations. Two major (2n = 50, 4n = 100) and three minor (3n = 75, 5n = 125, 6n = 150)...

Length-weight relationships (LWRs) of diploid and tetraploid loach Misgurnus anguillicaudatus from the Yangtze River basin, China were estimated and compared.

The purpose of present study was purification and partial characterization of liver peroxidase from Pb+Cd metal mixture stressed and controlled Labeo rohita. Purification of liver peroxidase was carried out by the combination of ammonium sulfate precipitations, ion exchange chromatography and Sephadex G-75 superfine gel filtration chromatography. S...

Enzymes are necessary for normal cellular metabolism. Catalase enzymes play an important role in the protection of tissues from the toxic effects of reactive oxygen species. The present study was designed to partially characterize liver catalase enzyme after purification from controlled and metal mixture stressed Ctenopharyngodon idella. Purificati...

Extensive industrialization and urbanization has increased the concentration of heavy metals into the aquatic environment. The polluted environment of fish may interfere with metabolic activities of fish. Catalase is a well-known antioxidant enzyme and act as a biomarker to protect the fish against the oxidative stress. To studies these interferenc...

To determine the genotype with better traits for aquaculture practices of the loach, factorial crosses were made among diploid (D), tetraploid (T) dojo loach, Misgurnus anguillicaudatus, and large-scale loach, Paramisgurnus dabryanus (P), producing DD, DT, DP, TD, TT, TP, PD, PT, and PP genotypes (female listed first). The growth performance and su...

A feeding trial was conducted for 8 weeks to evaluate the effects of graded levels of neutral phytase supplementation using pretreatment or spraying method on growth performance, body composition, bone mineral content and serum biochemical parameter in grass carp, Ctenopharyngodon idellus. A control diet without phytase was added and six additional...

Natural occurrence of pentaploid loach, Misgurnus anguillicaudatus discovered from Liangzi Lake area, Hubei Province, central China, is reported here for the first time. The evidences from karyotyping, DNA content analysis and nuclear volume measurements were described to confirm the pentaploid nature of the identified individual. This individual w...

The genetic diversity of Glyptosternum maculatum populations from Nyang River, Lhasa River, and Shetongmon Reach of Yarlung Zangbo River was assessed using six microsatellite markers. Overall, the genetic diversity across the three populations was low. The Shetongmon population exhibited the highest level of genetic diversity in terms of number of...

Yellowcheek carp (Elopichthys bambusa) is the only species of genus Elopichthys. It is widely distributed in Chinese freshwaters but currently its populations have declined to threatening level. We examined the genetic diversity and population structure of E. bambusa in the Yangtze River basin. A total of nine polymorphic microsatellite markers wer...

Nine yellowcheek (Elopichthys bambusa) microsatellite loci were isolated using the fast isolation by AFLP of sequences containing repeats (FIASCO) protocol. Three to eight alleles per locus were detected in 29 samples collected from five populations of E. bambusa. The mean number of alleles was 5.6±1.9 and the level of observed heterozygosities ran...

Natural occurrence of hexaploid loach Misgurnus anguillicaudatus detected in central China is reported here for the first time. The evidences from karyotyping, DNA content analysis and nuclear volume measurements were described to confirm the hexaploid nature of the identified individual.

We determined the genetic diversity of geographic populations from three spawning grounds (Nyang River, Lhasa River, Shetongmon Reach of Yarlung Zangbo River) of Glyptosternum maculatum with amplified fragment length polymorphism (AFLP) markers. Five primer combinations detected 332 products, 51 of them (15.4%) were polymorphic in at least one popu...

To determine the cytotype with better traits for the aquaculture practices of the dojo loach Misgurnus anguillicaudatus from the viewpoint of fish farming improvement, factorial crosses (2n♀×2n♂, 2n♀×4n♂, 4n♀×2n♂, 4n♀×4n♂) were conducted between natural diploids (D) and tetraploids (T), producing DD, DT, TD, and TT groups (female listed first). The...

Haematological and serum biochemistry parameters were studied and compared between cultured and wild ecotypes of Dojo loach Misgurnus anguillicaudatus during the prime fishing season, i.e. May-August. Data were analysed for the impact of feeding regime and other ecological conditions on the physiology of fish. The results revealed that haemoglobin,...

In search for an easy, rapid and cost-effective method to determine the ploidy levels of diploid and tetraploid dojo loaches Misgurnus anguillicaudatus distributed naturally in China, direct (karyotyping) and indirect (flow cytometry, erythrocyte nuclear measurements and morphometric analysis) methods were compared. The results revealed that all te...

To obtain the phylogenetic relationship between diploid and tetraploid Misgurnus anguillicaudatus, the mitochondrial cyt b gene in the diploid and tetraploid weather loach were isolated and sequenced. The DNA sequences were analyzed using MEGA 3.0 software to determine the phylogenetic relationship. Forty-five variable sites among cyt b gene sequen...

The purpose of this study was to determine whether diploid, triploid and tetraploid loach (Misgurnus anguillicaudatus) differed in terms of their main haematological and physiological characteristics. Diploid and tetraploid fish were produced by crossing of natural diploids (2n x 2n) and natural tetraploids (4n x 4n), respectively. Triploid fish we...

The peripheral blood cells of one-year-old Chinese sturgeon (Acipenser sinensis) have been studied by light microscopy and transmission electron microscopy. The erythrocyte count was 84.86×104cellmm−3 in the peripheral blood of the fish and that of leukocytes was 2.24×104cellmm−3. The erythrocytes and four main types of leucocyte—thrombocytes, lymp...

For production enhancement and procedure upgrade, the developmental phases of laboratory-reared eggs of catfishPelteobagrus fulvidraco were investigated. Twenty mature females and 10 males were collected from Dadongmen wholesale fisheries market in Wuhan City on May 8, 2003. Zygotes were stripped from mature fish after hormone-induced ovulation, fe...

Without Abstract

The present project was planned to compare the performance of fresh and dry cowdung in major carps (Labeo rohita, Catla catla and Cirrhinus mrigala). The experiment was conducted for five months using three earthen ponds. Each pond was stocked with 20 Labeo rohita, 15 Catla catla, and 15 Cirrhinus mrigala. Manuring of treated ponds with fresh and d...