The Search for Antidotes Against Ricin.

The castor plant (Ricinus communis) is primarily known for its seeds, which contain a unique fatty acid called ricinoleic acid with several industrial and commercial applications. Castor seeds also contain ricin, a toxin considered a chemical and biological warfare agent. Despite years of investigation, there is still no effective antidote or vaccine available. However, some progress has been made, and the development of an effective treatment may be on the horizon. To provide an updated overview of this issue, we have conducted a comprehensive review of the literature on the current state of research in the fight against ricin. This review is based on the reported research and aims to address the challenges faced by researchers, as well as highlight the most successful cases achieved thus far. Our goal is to encourage the scientific community to continue their efforts in this critical search.

The dangers of castor oil tea in neonates in rural Haiti: A case report.

During a 2-year period, eight cases of a distinct illness were seen among 1,424 neonates admitted to a newly established neonatal care unit in southern Haiti. The newborns presented with a picture of sepsis with shock, vomiting, hypotonia, lethargy, and abdominal distention. Five cases proved fatal and another case left the hospital against advice in extremis with little chance of survival. In each case, the illness was associated with a history of ingestion of teas that included castor oil, known as lok in Haitian Creole. The presumptive cause of the illness was established by the presence of a dark, oily substance in drainage from the nares and nasogastric tubes and by subsequent admission on direct questioning of the caregivers, who said that the infants had been given large amounts of lok. The castor oil tea had been given to three infants in the immediate neonatal period where its use is attributed to encouraging the passage of meconium. The five remaining infants were between 15 and 30 days of life when they were given lok shortly before admission to the neonatal unit for treatment of an undefined illness. All of them were term infants with no identified risks at birth. As nasogastric tubes are not routinely placed in sick neonates, and the parents did not volunteer information about lok administration, the practice may be more widespread than that recorded here. Although our data are confined to observations in Haiti, the use of traditional medicines is a globally widespread phenomenon. Attention must be drawn to the potential toxicity of such preparations and means found to ban their use in neonates.

Discovery of RTA ricin subunit inhibitors: a computational study using PM7 quantum chemical method and steered molecular dynamics.

Ricin is a potent toxin derived from the castor bean plant and comprises two subunits, RTA and RTB. Because of its cytotoxicity, ricin has alarmed world authorities for its potential use as a chemical weapon. Ricin also affects castor bean agribusiness, given the risk of animal and human poisoning. Over the years, many groups attempted to propose small-molecules that bind to the RTA active site, the catalytic chain. Despite such efforts, there is still no effective countermeasure against ricin poisoning. The computational study carried out in the present work renews the discussion about small-molecules that may inhibit this toxin. Here, a structure-based virtual screening protocol capable of discerning active RTA inhibitors from inactive ones was performed to screen over 2 million compounds from the ZINC database to find novel scaffolds that strongly bind into the active site of the RTA. Besides, a novel score method based on ligand undocking force profiles and semi-empirical quantum chemical calculations provided insights into the rescore of docking poses. Summing up, the filtering steps pointed out seven main compounds, with the SCF00-451 as a promising candidate to inhibit the killing activity of such potent phytotoxin.

Identification of novel potential ricin inhibitors by virtual screening, molecular docking, molecular dynamics and MM-PBSA calculations: a drug repurposing approach.

Ricin is a potent cytotoxin with no available antidote. Its catalytic subunit, RTA, damages the ribosomal RNA (rRNA) of eukaryotic cells, preventing protein synthesis and eventually leading to cell death. The combination between easiness of obtention and high toxicity turns ricin into a potential weapon for terrorist attacks, urging the need of discovering effective antidotes. On this context, we used computational techniques, in order to identify potential ricin inhibitors among approved drugs. Two libraries were screened by two different docking algorithms, followed by molecular dynamics simulations and MM-PBSA calculations in order to corroborate the docking results. Three drugs were identified as potential ricin inhibitors: deferoxamine, leucovorin and plazomicin. Our calculations showed that these compounds were able to, simultaneously, form hydrogen bonds with residues of the catalytic site and the secondary binding site of RTA, qualifying as potential antidotes against intoxication by ricin.Communicated by Ramaswamy H. Sarma.

An Electrochemical Approach to Follow and Evaluate the Kinetic Catalysis of Ricin on hsDNA.

International authorities classify the ricin toxin, present in castor seeds, as a potential agent for use in bioterrorism. Therefore, the detection, identification, and characterization of ricin are considered the first actions for its risk assessment during a suspected exposure, parallel to the development of therapeutic and medical countermeasures. In this study, we report the kinetic analysis of electro-oxidation of adenine released from hsDNA by the catalytic action of ricin by square wave voltammetry. The results suggest that ricin-mediated adenine release exhibited an unusual kinetic profile, with a progress curve controlled by the accumulation of the product and the values of the kinetic constants of 46.6 µM for Km and 2000 min-1 for kcat, leading to a catalytic efficiency of 7.1 × 105 s-1 M-1.

A Simple, Fast and Portable Method for Electrochemical Detection of Adenine Released by Ricin Enzymatic Activity.

International authorities classify ricin toxin present in castor seed as a potential agent for use in bioterrorism. Therefore, the detection, identification, and characterization of ricin in various sample matrices are considered necessary actions for risk assessment during a suspected exposure. This study reports a portable electrochemical assay for detecting active ricin based on the adenine electro-oxidation released from herring sperm DNA substrate by its catalytic action. Also, kinetic parameters were calculated, and the values were Km of 3.14 µM and Kcat 2107 min-1. A linear response was found in optimized experimental conditions for ricin concentrations ranging from 8 to 120 ng/mL, and with a detection limit of 5.14 ng/mL. This proposed detection strategy emphasizes the possibility of field detection of active ricin in food matrices and can be applied to other endonucleolytic activities.

Near-fatal poisoning after ricin injection.

OBJECTIVE: To report a near-fatal poisoning after intentional injection of ricin from a castor bean (Ricinus communis) extract. CASE REPORT: A 21 year-old man self-injected ∼3 mL of a castor bean extract intramuscularly and subcutaneously in the left antecubital fossa. Upon admission to our ED (1 h post-exposure; day 1, D1) he was awake and alert, but complained of mild local pain and showed slight local edema and erythema. He evolved to refractory shock (∼24 h post-exposure) that required the administration of a large volume of fluids and high doses of norepinephrine and vasopressin, mainly from D2 to D4. During this period, he developed clinical and laboratory features compatible with systemic inflammatory response syndrome, multiple organ dysfunction, capillary leak syndrome, rhabdomyolysis, necrotizing fasciitis and possible compartment syndrome. The patient underwent forearm fasciotomy on D4 and there was progressive improvement of the hemodynamic status from D7 onwards. Wound management involved several debridements, broad-spectrum antibiotics and two skin grafts. Major laboratory findings within 12 days post-exposure revealed hypoalbuminemia, proteinuria, thrombocytopenia, leukocytosis and increases in cytokines (IL-6, IL-10 and TNF-α), troponin and creatine kinase. Ricin A-chain (ELISA) was detected in serum up to D3 (peak at 24 h post-exposure), with ∼79% being excreted in the urine within 64 h post-exposure. Ricinine was detected in serum and urine by LC-MS up to D5. A ricin A-chain concentration of 246 µg/mL was found in the seed extract, corresponding to the injection of ∼738 µg of ricin A-chain (∼10.5 µg/kg). The patient was discharged on D71, with limited range of motion and function of the left forearm and hand. CONCLUSION: Ricin injection resulted in a near-fatal poisoning that evolved with septic shock-like syndrome, multiple organ dysfunction and necrotizing fasciitis, all of which were successfully treated with supportive care.

Ligand-Based Virtual Screening, Molecular Docking, Molecular Dynamics, and MM-PBSA Calculations towards the Identification of Potential Novel Ricin Inhibitors.

Ricin is a toxin found in the castor seeds and listed as a chemical weapon by the Chemical Weapons Convention (CWC) due to its high toxicity combined with the easiness of obtention and lack of available antidotes. The relatively frequent episodes of usage or attempting to use ricin in terrorist attacks reinforce the urge to develop an antidote for this toxin. In this sense, we selected in this work the current RTA (ricin catalytic subunit) inhibitor with the best experimental performance, as a reference molecule for virtual screening in the PubChem database. The selected molecules were then evaluated through docking studies, followed by drug-likeness investigation, molecular dynamics simulations and Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) calculations. In every step, the selection of molecules was mainly based on their ability to occupy both the active and secondary sites of RTA, which are located right next to each other, but are not simultaneously occupied by the current RTA inhibitors. Results show that the three PubChem compounds 18309602, 18498053, and 136023163 presented better overall results than the reference molecule itself, showing up as new hits for the RTA inhibition, and encouraging further experimental evaluation.

Use of Castor Bean Meal, Biodiesel Industry Coproduct, in A Lamb Production System Using Creep-Feeding in Brazil.

This study aimed to evaluate the replacement of soybean meal by detoxified castor bean meal on the intake and digestibility of nutrients, body weight gain, carcass yield, physiological and urinary parameters, and creep-feeding method effectiveness. For this trial, 43 male lambs were used, Dorper × Santa Inês, with an average initial body weight of 7.95 kg, 15 days old. Lambs were distributed in a randomized block design. Five experimental diets were provided: Without supplementation, with supplementation but without the use of castor bean meal, and with gradual levels of replacement of soybean meal by detoxified castor bean meal (33%, 67%, and 100%). Higher values of DMI and nutrient digestibility (p < 0.05) were observed for animals that received supplements. The milk intake did not differ among the diets. The DMD showed a linear effect, while NDFD had a quadratic effect, depending on castor bean meal inclusion. The carcass yield did not differ between experimental diets. There was no significant effect on the urinary volume and metabolites investigated. In conclusion, the replacement of soybean meal by detoxified castor bean meal does not compromise animals' development. Besides, the creep-feeding method positively affects lamb development, with higher body weight gain for supplemented animals.

Detoxified castor in the diets of dairy goats: II. Lactation curves, composition, and fatty acid profile of milk

We aimed to evaluate the lactation curves, composition, and fatty acid profile of milk of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and 43±2.97 kg body weight, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The lactation curves showed greater persistence of lactation in Saanen goats. There were significant effects of diets on the profile of some fatty acids present in the milk. We observed that the NaOH DCC diet led to an increase in desirable fatty acid content. Both Ca(OH)2 and NaOH DCC diets led to decreased milk production during the lactation period; however, the NaOH DCC diet led to high productive efficiency. Furthermore, NaOH DCC did not negatively affect the desirable fatty acid content, unlike Ca(OH)2 DCC. Diets formulated with detoxified castor decrease the production of milk from goats during lactation phase. It should be emphasized that milk produced by goats fed DCC diets does not contain unwanted waste.(AU)

Detoxified castor in the diets of dairy goats: I. Effects on intake, digestibility, and renal and hepatic parameters

The objective was to evaluate the intake, digestibility, nitrogen balance, and metabolic profile of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and body weights of 43±2.97 kg, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The diets significantly influenced the intake of dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), and total digestible nutrients (TDN). We observed a higher dry matter intake (DMI) in goats fed SM, similar to that of goats fed Ca(OH)2 DCC. Intake of nutrients followed the same trend as DMI. There was no significant effect of diets on digestibility of DM, CP, EE, and NDF; however, we observed a significant effect of diets on the levels of nitrogen intake (NI) and urinary nitrogen (UN). The goats fed SM consumed a larger quantity of nitrogen, but all had the same nitrogen balance, indicating that goats fed DCC were more efficient. The diets did not influence renal and hepatic parameters. Inclusion of castor cake in the diet of goats in confinement is an attractive option, considering that goats fed DCC present lower feed conversion, and its use does not cause hepatic and renal alterations, suggesting that SM can be completely replaced.(AU)

Terrorismo químico: proposta de modelagem de risco envolvendo ricina em eventos de grande visibilidade no Brasil / Chemical terrorism: risk modeling proposal for attacks involving ricin in mass gatherings in Brazil

RESUMO Grandes eventos estão no centro de estratégias terroristas e vem-se repetindo com frequência no âmbito internacional. Durante os últimos anos, o Brasil é palco de megaeventos esportivos; e este ano sediará a Copa do Mundo Fifa Sub-17. Assume-se que a maior exposição, nesses contextos, aumenta a vulnerabilidade ante as ameaças não convencionais, assim, é necessário que o planejamento da segurança brasileira seja apoiado em estudos sobre gestão de risco. Considera-se que um maior conhecimento sobre o tema é o primeiro passo para um sistema de defesa eficiente. A literatura apresenta relatos de episódios de emprego da ricina como arma química. Assim, este estudo objetivou avaliar a probabilidade de risco de um ataque terrorista com ricina, em um modelo matemático. Para isso, foi utilizada a teoria dos jogos e a equação de probabilidade de Major para análise de risco de terrorismo. A escolha da ricina justifica-se pelo fato de se tratar de uma biotoxina de extração relativamente simples, proveniente da mamona, que é uma planta endêmica no território brasileiro. Os parâmetros analisados foram os recursos de ataque, defesa e valor do alvo. A equação de probabilidade foi otimizada para defesa.

ABSTRACT Mass gatherings are at the center of terrorist strategies and are being repeated more frequently at international level. During the last years, Brazil has been the stage of mass gatherings, and it is supposed to host the Fifa Sub-17 World Cup this year. It is assumed that large exposure in these contexts increases vulnerability to threats, therefore it is necessary that safety planning be supported in risk management studies. It is considered that a greater knowledge of the topic is the first step towards an efficient defense system. This study aims to evaluate the probability of a ricin terrorist attack on a mathematical model. Existing literature shows reports of episodes of use of ricin as a chemical weapon. The choice of ricin is justified because it's a relatively easy biotoxin extraction from castor bean, which is an endemic plant in the Brazilian territory. For such study, we used game theory and the Major probability equation for terrorism risk analysis. The parameters analyzed were the resources of attack, defense, and value of the target. The probability equation has been optimized for defense.

A New Method for Extraction and Analysis of Ricin Samples through MALDI-TOF-MS/MS.

We report for the first time the efficient use of accelerated solvent extraction (ASE) for extraction of ricin to analytical purposes, followed by the combined use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and MALDI-TOF MS/MS method. That has provided a fast and unambiguous method of ricin identification for in real cases of forensic investigation of suspected samples. Additionally, MALDI-TOF MS was applied to characterize the presence and the toxic activity of ricin in irradiated samples. Samples containing ricin were subjected to ASE, irradiated with different dosages of gamma radiation, and analyzed by MALDI-TOF MS/MS for verification of the intact protein signal. For identification purposes, samples were previously subjected to SDS-PAGE, for purification and separation of the chains, followed by digestion with trypsin, and analysis by MALDI-TOF MS/MS. The results were confirmed by verification of the amino acid sequences of some selected peptides by MALDI-TOF MS/MS. The samples residual toxic activity was evaluated through incubation with a DNA substrate, to simulate the attack by ricin, followed by MALDI-TOF MS/MS analyses.

Cell toxicity by ricin and elucidation of mechanism of Ricin inactivation.

Castor cake is a by-product of the extraction of oil from from seeds of castor plants (Ricinus communis). This by-product contains high levels of proteins, but a toxic protein, ricin, limits its use as an animal feed. Ricin can be efficiently inactivated by treatment with calcium oxide (CaO), which can be evaluated by a cytotoxicity assay using LLC-MK2 cells. The mechanism by which the CaO treatment inactivates ricin, however, is unclear. We report the structural changes responsible for ricin inactivation. Purified ricin was treated with 0.6% CaO and then analyzed by mass spectrometry. This treatment degraded the ricin at preferential sites. The aqueous CaO solution had a pH >12, which preferentially cleaved asparagine residues, followed by glutamine, serine and glycine residues. The alkaline pH affected the tertiary structure of the ricin, cleaving its polypeptide chains and thereby eliminating its cytotoxic activity.

Avaliação de diferentes processos de destoxificação sobre o valor nutricional e energético da torta de mamona para suínos / Evaluation of different detoxification procedures on nutritional and energy value of castor bean cake for pigs

O objetivo do presente estudo foi avaliar o valor nutricional e energético da torta de mamona destoxificada por diferentes métodos para suínos em crescimento. Foram utilizados 24 suínos machos, castrados, distribuídos em seis tratamentos, sendo uma ração referência e cinco rações testes (75% da dieta referência e 25% das tortas de mamona) contendo a torta de mamona destoxificada pelos métodos do hidróxido de cálcio, da autoclavagem, do hidróxido de cálcio+ensilagem, da autoclavagem+ensilagem e da extrusão. As tortas de mamona submetidas aos processos de destoxificação com hidróxido de cálcio e autoclavagem resultaram em maior teor de proteína digestível. Para o valor de energia metabolizável, os processos de destoxificação com hidróxido de cálcio, autoclavagem, hidróxido de cálcio+ensilagem e extrusão não diferiram entre si. Considerando-se a valoração nutricional e energética da torta de mamona por meio dos processos de destoxificação, os métodos com uso de hidróxido de cálcio e autoclavagem são os mais eficientes.(AU)

The aim of this study was to evaluate the nutritional and energy value of castor bean cake detoxified by different methods for growing pigs. A total of 24 barrows was distributed in six treatments, being in a reference diet and 5 test diets (75% of the reference diet and 25% of castor beam cake) containing castor bean cake detoxified by the method of calcium hydroxide, autoclaving, calcium hydroxide + silage, autoclaving + silage and extrusion. Castor bean cake subjected to detoxification processes with calcium hydroxide and autoclaving resulted in higher content of digestible protein. For the metabolizable energy value, the process of detoxification with calcium hydroxide, autoclaving, calcium hydroxide+silage, and extrusion did not differ. Considering the nutritional and energy valuation of castor bean cake detoxified by different procedures, the methods using calcium hydroxide and autoclaving were the most efficient.

Avaliação de diferentes processos de destoxificação sobre o valor nutricional e energético da torta de mamona para suínos / Evaluation of different detoxification procedures on nutritional and energy value of castor bean cake for pigs

O objetivo do presente estudo foi avaliar o valor nutricional e energético da torta de mamona destoxificada por diferentes métodos para suínos em crescimento. Foram utilizados 24 suínos machos, castrados, distribuídos em seis tratamentos, sendo uma ração referência e cinco rações testes (75% da dieta referência e 25% das tortas de mamona) contendo a torta de mamona destoxificada pelos métodos do hidróxido de cálcio, da autoclavagem, do hidróxido de cálcio+ensilagem, da autoclavagem+ensilagem e da extrusão. As tortas de mamona submetidas aos processos de destoxificação com hidróxido de cálcio e autoclavagem resultaram em maior teor de proteína digestível. Para o valor de energia metabolizável, os processos de destoxificação com hidróxido de cálcio, autoclavagem, hidróxido de cálcio+ensilagem e extrusão não diferiram entre si. Considerando-se a valoração nutricional e energética da torta de mamona por meio dos processos de destoxificação, os métodos com uso de hidróxido de cálcio e autoclavagem são os mais eficientes.(AU)

The aim of this study was to evaluate the nutritional and energy value of castor bean cake detoxified by different methods for growing pigs. A total of 24 barrows was distributed in six treatments, being in a reference diet and 5 test diets (75% of the reference diet and 25% of castor beam cake) containing castor bean cake detoxified by the method of calcium hydroxide, autoclaving, calcium hydroxide + silage, autoclaving + silage and extrusion. Castor bean cake subjected to detoxification processes with calcium hydroxide and autoclaving resulted in higher content of digestible protein. For the metabolizable energy value, the process of detoxification with calcium hydroxide, autoclaving, calcium hydroxide+silage, and extrusion did not differ. Considering the nutritional and energy valuation of castor bean cake detoxified by different procedures, the methods using calcium hydroxide and autoclaving were the most efficient.

Time-course proteome analysis of developing extrafloral nectaries of Ricinus communis.

Floral and extrafloral nectaries are unique organs that secrete energy rich chemical components, but their contribution for nectar production is largely unknown. Here, we present the first comparative proteome dataset of four developmental stages of the extrafloral nectaries from castor plant (Ricinus communis), an important biofuel crop. Respectively, from stage I-IV, we identified 626, 613, 449 and 356 proteins, respectively, summing up 882 nonredundant proteins. Surprisingly, we identified two isoforms of the potent toxin ricin, indicating that ricin expression is not limited to seeds, but it may serve a general defense purpose for the castor plant. To date, this is the most complete dataset of proteins either from floral or extrafloral nectaries, thus contributing to lay the foundations for investigations on their ecological and evolutionary importance.

Torta de mamona destoxificada para alimentação de poedeiras comerciais / Detoxified castor cake feed for laying hens

Objetivou-se com este experimento avaliar o efeito da inclusão de torta de mamona destoxificada (TMD) na ração de poedeiras comerciais sobre o desempenho e a qualidade interna e externa dos ovos. Foram utilizadas 200 poedeiras comerciais de 40 a 50 semanas de idade, da linhagem Hy-Line W-36®, com 1543±34g de peso corporal, que foram distribuídas em um delineamento inteiramente casualizado com cinco tratamentos (0, 5, 10, 15 e 20% de torta de mamona destoxificada na ração) com cinco repetições de oito aves cada. Foram avaliados o consumo de ração, a produção, o peso e a massa de ovos e a conversão alimentar. A qualidade interna foi avaliada por meio da unidade de Haugh, percentual de albúmen e de gema. A qualidade da casca foi medida pela espessura, densidade específica e percentual de casca. As variáveis de desempenho foram afetadas pela inclusão da TMD com resposta linear negativa para o consumo de ração e quadrática para produção de ovos, peso do ovo, massa do ovo e conversão alimentar, com os melhores níveis de 10,5, 5,7, 9,2 e 10,3% respectivamente. Não houve efeito significativo da inclusão da TMD para as variáveis de qualidade interna e externa dos ovos. Concluiu-se que a TMD pode ser incluída na ração de poedeiras em até 5,7% para otimizar o desempenho e não alterar a qualidade interna e externa dos ovos.(AU)

This experiment aimed to evaluate the use of detoxified castor cake (DCC) in the diet of laying hens on performance and internal and external quality of eggs. A total of 200 laying hens with 40-50 weeks of age, of Hy-Line W-36® line, with 1543±34g body weight, were distributed in a completely randomized design with five treatments (0, 5, 10, 15 and 20% of DCC in diet) with five replicates of eight birds each. The feed intake, egg production, egg weight, egg mass and feed conversion were evaluated. The egg internal quality was evaluated by Haugh unit, percentage of albumen and yolk. The shell quality was evaluated by the thickness, density and specific percentage of eggshell. The performance variables were affected by the inclusion of DCC with a negative linear response to food intake and quadratic for egg production, egg weight, egg mass and feed conversion, with the best levels of 10.5, 5.7, 9.2 and 10.3% respectively. There was no significant effect of DCC inclusion for the variables of egg quality. It is conclude that the DCC can be included in hens diets up to 5.7% to optimize performance and do not alter the internal and external quality of the eggs.(AU)

Torta de mamona destoxificada para alimentação de poedeiras comerciais / Detoxified castor cake feed for laying hens

Objetivou-se com este experimento avaliar o efeito da inclusão de torta de mamona destoxificada (TMD) na ração de poedeiras comerciais sobre o desempenho e a qualidade interna e externa dos ovos. Foram utilizadas 200 poedeiras comerciais de 40 a 50 semanas de idade, da linhagem Hy-Line W-36®, com 1543±34g de peso corporal, que foram distribuídas em um delineamento inteiramente casualizado com cinco tratamentos (0, 5, 10, 15 e 20% de torta de mamona destoxificada na ração) com cinco repetições de oito aves cada. Foram avaliados o consumo de ração, a produção, o peso e a massa de ovos e a conversão alimentar. A qualidade interna foi avaliada por meio da unidade de Haugh, percentual de albúmen e de gema. A qualidade da casca foi medida pela espessura, densidade específica e percentual de casca. As variáveis de desempenho foram afetadas pela inclusão da TMD com resposta linear negativa para o consumo de ração e quadrática para produção de ovos, peso do ovo, massa do ovo e conversão alimentar, com os melhores níveis de 10,5, 5,7, 9,2 e 10,3% respectivamente. Não houve efeito significativo da inclusão da TMD para as variáveis de qualidade interna e externa dos ovos. Concluiu-se que a TMD pode ser incluída na ração de poedeiras em até 5,7% para otimizar o desempenho e não alterar a qualidade interna e externa dos ovos.

This experiment aimed to evaluate the use of detoxified castor cake (DCC) in the diet of laying hens on performance and internal and external quality of eggs. A total of 200 laying hens with 40-50 weeks of age, of Hy-Line W-36® line, with 1543±34g body weight, were distributed in a completely randomized design with five treatments (0, 5, 10, 15 and 20% of DCC in diet) with five replicates of eight birds each. The feed intake, egg production, egg weight, egg mass and feed conversion were evaluated. The egg internal quality was evaluated by Haugh unit, percentage of albumen and yolk. The shell quality was evaluated by the thickness, density and specific percentage of eggshell. The performance variables were affected by the inclusion of DCC with a negative linear response to food intake and quadratic for egg production, egg weight, egg mass and feed conversion, with the best levels of 10.5, 5.7, 9.2 and 10.3% respectively. There was no significant effect of DCC inclusion for the variables of egg quality. It is conclude that the DCC can be included in hens diets up to 5.7% to optimize performance and do not alter the internal and external quality of the eggs.

Cloning and chloroplast-targeted expression studies of insect-resistant gene with ricin fusion-gene under chloroplast transit peptide in cotton

Background: Transgenic plants inhabiting single Bt gene are prone to develop insect resistance and this resistance has been reported in case of some important yield-devastating insect larvae of commercial crops, such as cotton and rice. Therefore, it has become essential to adapt new strategies to overcome the problem of insect resistance and these new strategies should be sophisticated enough to target such resistant larvae in broad spectrum. Among these, plants may be transformed with Bt gene tagged with some fusion-protein gene that possesses lectin-binding capability to boost the binding sites for crystal protein gene within insect mid-gut in order to overcome any chances of insect tolerance against Bt toxin. Enhanced chloroplast-targeted Bt gene expression can also help in the reduction of insect resistance. Results: In the present investigation, a combined effect of both these strategies was successfully used in cotton (G. hirsutum). For this purpose, plant expression vector pKian-1 was created, after a series of cloning steps, carrying Cry1Ac gene ligated with chloroplast transit peptide towards N-terminal and Ricin B-Chain towards C-terminal, generating TP-Cry1Ac-RB construct. Conclusions: Efficacy of pKian-1 plasmid vector was confirmed by in-planta Agrobacterium-mediated leaf GUS assay in tobacco. Cotton (G. hirsutum) local variety MNH-786 was transformed with pKian-1 and the stable integration of TP-Cry1Ac-RB construct in putative transgenic plants was confirmed by PCR; while fusion-protein expression in cytosol as well as chloroplast was substantiated by Western blot analysis. Whereas, confocal microscopy of leaf-sections of transgenic plants exposed that hybrid-Bt protein was expressing inside chloroplasts.