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In-house receptors (IHRs) were isolated from non-immunized poultry liver to analyze selected contaminants and residues in targeted food and feed using

Background Kell is highly immunogenic after ABO and Rh blood group system, and anti-Kell antibodies have been linked to hemolytic transfusion reaction and fetal hemolytic disease in newborns. The antithetic KEL1/KEL2, KEL3/KEL4, and KEL6/KEL7 antigens are expressed in the Kell blood group system. At least 36 antigens are carried on a single 93 kDa red-cell trans-membrane protein in the Kell blood system. This study aimed to review different literature on the kell blood group and associated phenotypes and to find out the epidemiology and frequency of different Kell antigens all over the world. Methods Epidemiological studies of Kell antigens (2000 to 2022) were extracted to capture all reported data of different kell genotypes/phenotypes from different populations. Different databases like Google Scholar, PubMed, JSTOR, Scopus, and Science Direct were accessed to download all the published data reporting different percentages of kell antigens. Results A total of 250 research papers and articles were downloaded; 60 studies met our inclusion criteria. Most of the research studies consisted of KEL1/KEL2, KEL3/ KEL4, and KEL6/KEL7. According to this meta-analysis, the prevalence of KEL1 and KEL3 are lower than KEL2 (100%) and KEL4 (100%). In all captured studies the prevalence of KEL1 ranged from 0 to 23.6%, KEL2 from 0 to 100%, KEL3 from 0 to 11.7%, KEL4 100%, KEL5 0%, KEL6 100%, and KEL7 was 97.31%. Discussion This is the first meta-analysis to check the occurrence of Kell blood antigens frequency and the spectrum of variants associated with it in populations of the world. This review will help to identify which is the common antigen of the Kell blood group system and how it can affect the person by disease associated with it.

Three freshwater fish species viz. Labeo rohita, Cirrhinus mrigala and Gibelion catla, grown in brackish water ponds were analyzed for compositional properties to assess the potential of this habitat to produce nutritionally adequate fish for human consumption. Overall, the unsaturated fatty acids were lower in L. rohita (46.6%) than saturated fatty acids; while in C. mrigala and G. catla, the unsaturated fatty acids were 50.4% and 58.2%, respectively. The most abundant saturated fatty acid in examined species was palmitic acid (C16:0), 23.7 to 34.1%; mono-unsaturated fatty acid was oleic acid (C18:1) 19.6 to 31.7% and poly-unsaturated fatty acid linoleic acid (C18:2) 9.46 to 13.3%. A reasonable amount of essential fatty acids ω-3 (5.80 to 9.26%) and ω-6 (9.46 to 13.3%) was also found in these species while growing in brackish water on salt tolerant forages like Leptochloa fusca, Brachiaria mutica and Kochia indica as supplemental feed. The ω-3/ω-6 ratio was calculated as 0.46, 0.80 and 0.69 in L. rohita, C. mrigala and G. catla, respectively. The maximum EPA (eicosapentaenoic acid, C20:5) was observed in C. mrigala (2.23%), followed by G. catla (1.62%) and L. rohita (0.98%). While the DHA (docosahexanenoic acids, C22:6) was found maximum in G. catla (1.97%) and minimum in C. mrigala (0.95%). The results of body composition indicated that L. rohita found maximum protein contents (19.2%) with minimum total fats (1.28%) while C. mrigala found maximum total fats (2.11%) but minimum protein contents (18.3%). Overall results indicated that the Indian carps grown in brackish water have comparable chemical composition and nutritive value with the same species grown in freshwater medium.

An experiment was designed to contain eight feed consumption levels (ad libitum, 300, 330, 360, 390, 420, 450, 480 g/day/bird) to evaluate the effects of feed consumption levels on growth performance and apparent digestibility of nutrients for White Pekin ducks from 35 days to 42 days of age. Ninety-six 35-day-old male Pekin ducks were randomly assigned into eight treatments, each containing six replicate pens with two birds per pen. All birds of the treatment group 1 as the control group was fed ad libitum and the birds of the treatment groups from 2 to 8 were quantitatively fed by force-feeding. The feed intake was 300, 330, 360, 390, 420, 450, 480 g/day/bird for treatment groups 2 through 8, respectively. Results of growth performance showed that feed consumption levels affected final body weight and average daily gain significantly (P 0.05). Based on the broken-line regression model analysis with body weight gain data, the optimum feed consumption level for Pekin ducks w...

The present study was conducted to evaluate the extent of ß - lactam antibiotic, amoxicillin residues in market milk and meat. Samples were randomly collected from Faisalabad city, Pakistan. High Performance Liquid Chromatography (HPLC) method with inflorescent detector was used to detect, identify and quantify the amoxicillin residues in milk and meat samples. The milk samples were purified by performing a protein precipitation step, followed by derivatization. To clean up tissue samples, a liquid extraction, followed by a solid-phase extraction procedure C18 (4.0X4.6mm, 5μm) was performed. A 50% meat and 90% milk samples were found contaminated with residues. The residues of amoxicillin in milk were in range of 28 to 46μg/kg and in meat were 9 to 84μg/kg. All of the contaminated milk and 40 out of 50% meat samples fall in maximum residue limits.

A highly sensitive competitive ELISA was standardized to determine aflatoxin M1 (AFM1) in milk and dairy samples randomly collected from Faisalabad city, using Riedel-de-Haen, Aflatoxin M1 ELISA Systems, (Art–No. 45169). Standards of 5, 10, 25, 50, and 100 ng L−1 AFM1 in sample/standard buffer were used in optimizing anti-AFM1 antibodies and peroxidase–AFM1 conjugate. Linear standard curve showed increase in concentration (log C) accompanied by decrease in maximal absorbance (%B/B0) values (%B/B0 = 124.3 − 45.0 log C) with highly significant negative correlation (−0.973). The middle of the test (50% B/B0) was at 30 ng L−1 with 6.7 ng L−1 the lowest detection limit (90% B/B0). Duplicate analysis of 41 samples showed AFM1 levels below EC permissible limits (50 ng L−1) with maximums of 40, 13, and 7.4 ng L−1 in milk, yogurt and butter, respectively. However, possibility of exceeding limits cannot be excluded, and demands regular monitoring.

A highly sensitive enzyme immunoassay was standardized for aflatoxin B1 determination in poultry feed and its components using Riedel-de-Haen, ELISA Systems. A microtitration plate method was optimized using anti-aflatoxin B1 antibodies and peroxidase – aflatoxin B1 conjugate, based on competitive enzyme immunoassay principle. Standards of concentrations of 5, 10, 20, 50, 100, 500 ng/L aflatoxin B1, prepared in phosphate-buffered saline, were used. Standard curves showed that as the concentration of antigen decreased, absorbance values increased. Fifty percent inhibition was observed at 37 ng/L. Regression analysis showed that log concentration was inversely related to %B/B0, with a highly significant negative correlation (−0.980). The lowest detection limit for aflatoxin B1 was 5 ng/L. Using this standardized ELISA, aflatoxin B1 was detected in most of the commercially available poultry feed samples and their components. The data suggest that this test is suitable for the accurate determination of aflato...

A highly sensitive enzyme immunoassay is described for the detection of atrazine residues in water. Atrazine derivative was conjugated to Bovine Serum Albumin (BSA) to obtain an immunizing antigen and to Horseradish Peroxidase enzyme (POD) to obtain a marker for immunoassay. The formation of these conjugations was confirmed by UV spectroscopy as well as by gel-electrophoresis. Polyclonal antibodies were raised in rabbits by immunization with an atrazine-BSA conjugate containing 29 atrazine residues per BSA molecule. An ELISA on microtitration plates was optimized with peroxidase-atrazine conjugate. The middle of the test (50% B/Bo) was found to be at 90 ng/l, which is well below the maximum concentration permitted by the EC guidelines for drinking water. Detection limits for atrazine of about 1 ng/l could be reached. The assay did not require concentration or cleanup steps for drinking or ground water samples. Validation experiments showed good accuracy and precision. No cross-reactivities were shown by other s-triazines like terbutryn, ametryn, terbuthylazine, des-isopropylatrazine, and de-ethylatrazine except hydroxyatrazine. The latter was present at very low levels that can be calibrated/standardized before analysis or it may be considered as leftover residues of atrazine. Based on these results, it is suggested that this test can be applied to obtain fairly accurate results for atrazine concentration in water samples from different sources.

The effects of temperatures and solar radiation on the dissipation of 14C‐p,p'‐DDT from a loam soil was studied by quantifying volatilization, mineralization and binding. The major DDT loss occurred by volatilization, which was 1.8 times more at 45oC than at ambient temperature (30°C). Mineralization of DDT slowly increased with time but it decreased slightly with increase in temperature. Binding of DDT to soil was found to be less at higher temperatures (35 and 45°C) as compared to ambient temperature. Degradation of DDT to DDE was faster at higher temperatures. Exposure of non‐sterilized and sterilized soils treated with 14C‐DDT to sunlight in quartz and dark tubes for 6 weeks resulted in significant losses. Volatilization and mineralization in quartz tubes were more as compared to dark tubes. The volatilized organics from the quartz tubes contained larger amounts of p,p'‐DDE than the dark tubes. Further, higher rates of volatilization were found in non‐sterilized soils than in sterilized soils...

Dissipation of 14C‐p,p'‐DDT from water was studied for 180 days under outdoor conditions. DDT dissipated rapidly with overall half‐life of 53 days. The main degradation products were p,p'‐DDE and p,p'‐DDD. A portion of 14C‐residues was found in the sediment plus biomass (pellet) and on the inner surface of the glass container. This amounted to 7.2 and 6.7% of the initially added radioactivity, respectively. After 6 months, bound14C was more as compared to extractable 14C and p,p'‐DDD was the major metabolite of p,p'‐DDT in the extractable fraction. DDT dissipated from clay plates under indoor conditions with an overall half‐life of 160 days.

Dissipation and degradation of 14C‐p,p'‐DDT (Faisalabad and Peshawar locations) and 14C‐p,p'‐DDE (Faisalabad location) were studied for one year in soils under field conditions. Both DDT and DDE dissipated more rapidly under the Pakistani subtropical climate than reported for temperate regions. More binding to soil of 14C‐DDT was observed at Peshawar than that at Faisalabad. Overall halflives were 144 and 313 days in Faisalabad and Peshawar respectively. The main degradation products of p,p'‐DDT extracted from soils at the two locations were p,p'‐DDE and p,p'‐DDD. 14C‐DDE showed an overall halflife of 191 days under Faisalabad field conditions. Since the degradation of both DDT and DDE was not substantial, it is maintained that dissipation of both chemicals was largely due to volatilization/codistillation. About 68–92% of bound 14C‐residues from soils previously treated with 14C‐DDT were released by sulphuric acid treatment. Fresh soil inoculum also released up to 77% after three months. The resi...

A dipstick format was developed for on-site atrazine monitoring in water samples of different origins. It was derived from an in-house-developed ELISA based on polyclonal antibodies that also cross-react with hydroxyatrazine (30%) and terbuthylazine (17%). Test reagents were evaluated for temperature and pH stabilities and rapidity for field applications. Reagents performed well within a temperature range of 20-30°C and were tolerant to alkaline pH (up to 8.5) of the assay buffering system. Tracer incubation time could be reduced to 40 min. Bovine serum albumin addition (1%) in the assay buffer improved assay performance, giving 50% B/B0 (IC50) of 65 ng/L and the lowest LOD of 2 ng/L at 90 B/B0 (IC10). The dipstick ELISA format was standardized on a membrane support. Nylon membrane, positively charged, was superior to PVDF for qualitative or semiquantitative analysis regarding color intensity and stability. Tracer incubation time was further reduced to 30 min with a lowest LOD of 0.1 µg/L. For real sample screening with dipsticks, acceptable results were obtained for water. Significant correlation was found between dipstick and plate ELISA results. Validation using GC with a nitrogen-phosphorus detector and HPLC indicated that dipstick signals in aged water samples, which were mainly due to hydroxyatrazine, were significantly above European Commission regulations of 0.1 µg/L. However, dipsticks were superior, fast, and cost-effective.

In-house developed ELISA was standardized to monitor atrazine residues in different environmental samples. The standard curve was linear, indicating an increase in log concentration with decrease in absorbance (%B/B0 = 1.075–0.042 Log C; r = −0.966). The middle of the test was at 75 ng/L and the lowest detection limit at 4 ng/L. ELISA significantly correlated with the high performance liquid chromatography (HPLC) (r = 0.990). Internal validation showed good accuracy and precision. Maximum atrazine residues were present in Jehlum River water/sediments and maize/sugarcane plant roots. Most of the food samples were found to be contaminated. ELISA required less clean-up steps than HPLC, but showed matrix effect in soil/colored extracts.