Papers by Mayra A D Saleh
Journal of Veterinary Healthcare, Nov 3, 2017
The aim of this study was to establish the digestible threonine (dig. Thr) requirements and the i... more The aim of this study was to establish the digestible threonine (dig. Thr) requirements and the ideal proportion between Thr and Lys for Isa Brown laying hens on productive traits and egg quality characteristics from 55-to 58-and 59-to 61 weeks of age. Increased levels of L-Thr were added to a basal diet that contained 3.7 g/kg of dig. Thr. Therefore, diets containing 3.7, 4.0, 4.3, 4.6, 4.9 and 5.2 g/kg of dig. Thr and a relation between Thr and Lys of 0.58, 0.63, 0.67, 0.72, 0.77 and 0.81, respectively were provided to laying hens. A total of 216 hens were distributed in a randomized design among the 6 experimental diets. There were 9 replicates per treatment, and 4 birds per replicate. Data were analyzed by repeated measures analysis using the MIXED procedure of SAS. The main effects (dig. Thr level and experimental period) and their interaction were studied. Neither the dig. Thr level nor the experimental period had effect on performance traits and egg quality. Also, commercial egg grading was not influenced by period. However, there was a quadratic effect (P<0.001) of dig. Thr level within each scale egg weight. In conclusion, diets containing more than 3.7 g/kg of dig. Thr do not improve laying hens productivity at 55-to 61-week-old.
Livestock Science, 2018
Photoperiod and supplementary tryptophan can attenuate the effects of stressful weaning. However,... more Photoperiod and supplementary tryptophan can attenuate the effects of stressful weaning. However, few studies have evaluated tryptophan metabolism in the presence of light. This study aimed to evaluate the effects of tryptophan levels (TL) on the diet of weanling piglets submitted to different light programs (LP). Seventy-two piglets weaned at 21 days of age (starting weight 6.6 ± 2.33 kg) were used. The experimental design consisted of randomized blocks with 24 days of duration in a 2 × 2 factorial arrangement. Two LP were used: 12-h or 23-h light/day. Two digestible TL were used: 2.6 g or 5.2 g of Trp/kg feed on pre-starter I diet (from 0 to 14 trial days) and 2.4 g or 4.8 g of Trp/kg feed on pre-starter II diet (from 15 to 24 trial days). Six replicates of three animals per treatment were performed. Growth performance, blood glucose, plasma cortisol profiles and animal behavior were assessed. Blood glucose was measured on experimental days 0 and 24, and cortisol was measured on days 0 and 8. Behavior was observed on days 2, 9, 16 and 23. Neither growth performance nor blood glucose were affected by the interaction between LP and TL. The treatments did not influence daily weight gain, daily feed intake and blood glucose during the periods of 0-14, and 0-24 days. Feed:gain ratio improved during the 0-14 days period for piglets receiving 12-h light/day. The treatments did not influence the frequency of "moving" behaviors. However, the interaction between LP and TL affected the plasma cortisol and frequency of "feeding" and "lying" behaviors. Piglets that received the highest TL had lower plasma cortisol levels, reduced "feeding" behaviors and increased "lying" behaviors, compared to animals that received normal TL, when subjected to LP of 23-h light/day. The results suggest that use of LP of 23 h light/day is not indicated for piglets.
Journal of Animal Science and Research, 2017
Boletim de Indústria Animal, 2016
The objective of this study was to evaluate the performance of piglets fed two sources of oil (so... more The objective of this study was to evaluate the performance of piglets fed two sources of oil (soybean and palm oil) combined with maltodextrin and a blend of palm oil microencapsulated with maltodextrin, as well as the apparent digestibility coefficients of these diets. A total of 162 piglets weaned at 21 days, with a mean initial weight of 5.42 ± 0.55 kg, were allocated in a randomized block design consisting of three treatments and 18 replicates of three animals each. The following treatments were evaluated: T 1 : diet containing soybean oil [3.03% in the pre-initial (I) and initial (II) diets] and maltodextrin (10.0% in I and 5.93% in II); T 2 : diet containing palm oil (3.03% in I and II) and maltodextrin (10.0% in I and 5.93% in II); T 3 : diet containing a blend of palm oil microencapsulated with maltodextrin (10.0% in I and II) and maltodextrin added to the blend (4.07% in I) so that the percentage of maltodextrin would be identical in the diets of the three treatments. The performance and digestibility data were submitted to analysis of variance using the MIXED and GLM procedures, respectively, of the SAS package and means were compared by the Tukey test (P 0.05) in DFI, ADG or FC were observed between piglets submitted to the different treatments. The ADC of dry matter was 4.25% lower (P<0.05) for the diet containing palm oil microencapsulated with maltodextrin compared to the soybean oil diet. The ADC of ether extract was 54% higher (P<0.05) in the soybean oil diet compared to the palm oil diet, which negatively affected the ether extract digestibility coefficient. In conclusion, palm oil microencapsulated or not with maltodextrin can replace soybean oil in the diets of weaned piglets without compromising their performance.
... Eu amo muito vocês. Ao meu pai, João Dib Saleh Neto, in memoriam, pelo grande exemplo e por t... more ... Eu amo muito vocês. Ao meu pai, João Dib Saleh Neto, in memoriam, pelo grande exemplo e por todos os dias que esteve ao meu lado. ... amostras para a realização deste estudo. Aos companheiros de Pós-graduação Renato, Fábio, Tiago, Rafael, Emanuel, ...
The objective of this work was to evaluate the effects of dietary glutamine and glutamic acid sup... more The objective of this work was to evaluate the effects of dietary glutamine and glutamic acid supplementation on carbon turnover (δ13C) in the muscles of piglets, on animal performance, and on feed economic feasibility. The diets consisted of: control (C), 1% glutamine (G), and 1% glutamic acid (GA). In experiment I, 111 piglets were used to assess carbon turnover in the Masseter, Psoas major, and Abdominal internal oblique muscles in terms of their isotopic composition and 13C substitution over time. In experiment II, 72 piglets were assigned randomly to blocks (eight replicates per treatment and three animals per experimental unit), in order to evaluate animal performance and feed economic feasibility. The GA diet promoted the best 13C acceleration in the studied muscles. No diet effects were observed on performance variables. The G and GA diets presented higher costs than the C diet. Although supplementation with 1% glutamine or glutamic acid accelerates carbon turnover in the st...
Ciência Rural, 2017
ABSTRACT: Sorghum is the second cereal used in pigs’ diets in Brazil, which has a lower cost than... more ABSTRACT: Sorghum is the second cereal used in pigs’ diets in Brazil, which has a lower cost than corn, thus this experiment aimed to study the effects of high-moisture sorghum silage grain with high- and low-tannin contents on silage quality and piglets’ performance. A total of seventy-two weaned piglets were allocated into randomized blocks with six replicates and four treatments, based on diets with dry corn grain (DCG); dry sorghum grain with low-tannin (LTSG), high-moisture sorghum grain silage with low-(LTSS) and high-tannin (HTSS). The ensiling process decreased total and condensed tannin contents to 31% and 98% for LTSS and, to 80% and 93% for HTSS, respectively. No treatment effects observed on average daily feed intake and average daily weight gain. The feed:gain ratio of piglets fed LTSS was greater than piglets fed LTSG. At total period, piglets fed HTSS showed a similar feed:gain ratio than piglets fed DCG or LTSG, although it was worse than animals fed LTSS. The LTSS a...
Asian-Australasian Journal of Animal Sciences, 2015
Morphological and physiological alterations occur in the digestive system of weanling piglets, co... more Morphological and physiological alterations occur in the digestive system of weanling piglets, compromising the performance in subsequent phases. This experiment aimed at verifying the influence of glutamine, glutamate and nucleotides on the carbon turnover in the pancreas and liver of piglets weaned at 21 days of age. Four diets were evaluated: glutamine, glutamic acid or nucleotides-free diet (CD); containing 1% glutamine (GD); containing 1% glutamic acid (GAD) and containing 1% nucleotides (ND). One hundred and twenty-three piglets were utilized with three pigs slaughtered at day zero (weaning day) and three at each one of the experimental days (1, 2, 4, 5, 7, 9, 13, 20, 27, and 49 post-weaning), in order to collect organ samples, which were analyzed for the δ 13 C isotopic composition and compared by means of time. No differences were found (p>0.05) among treatments for the turnover of the 13 C in the pancreas (T 50% = 13.91, 14.37, 11.07, and 9.34 days; T 95% = 46.22, 47.73, 36.79, and 31.04 days for CD, GD, GAD, and ND, respectively). In the liver, the ND presented accelerated values of carbon turnover (T 50% = 7.36 and T 95% = 24.47 days) in relation to the values obtained for the GD (T 50% = 10.15 and T 95% = 33.74 days). However, the values obtained for the CD (T 50% = 9.12 and T 95% = 30.31 days) and GAD (T 50% = 7.83 and T 95% = 26.03 days) had no differences (p>0.05) among other diets. The technique of 13 C isotopic dilution demonstrated trophic action of nucleotides in the liver.
Journal of Animal Science and Biotechnology, 2015
A sample preparation method based on ultrasound assisted-extraction (UAE) of Ca, Mg and P from sw... more A sample preparation method based on ultrasound assisted-extraction (UAE) of Ca, Mg and P from swine feed has been described. The experiment was performed to cover the variables influencing the sonication process and, the method validation using standard reference material. Final solutions obtained upon sonication were analyzed by flame atomic absorption spectrometry (for Ca and Mg) and by UV-vis spectrophotometry (for P). The best conditions for metal extraction were as follows: sample mass: 100 mg in 20 mL 0.10 mol/L HCl, a particle size: <60 μm, sonication time: 5 cycles of 10 s and ultrasound power: 102 W. The UAE method was applied in digestibility assays in different piglet feeds and their results showed that it is highly comparable (P > 0.05) to the other methods used for such purposes, as block digestion, and offered a Ca, Mg and P method of quantification limit of 10.6, 12.4 and 14 mg/kg, respectively. The major advantages of the UAE method compared to other methods are the high treatment rate, low reagent usage in the extracts and, it does not generate toxic residues that might negatively affect human health and the environment, accompanied by good precision and accuracy.
Química Nova, 2009
Determinação De fósforo bioDisponível em rações De peixes utilizanDo extração assistiDa por ultra... more Determinação De fósforo bioDisponível em rações De peixes utilizanDo extração assistiDa por ultra-som e espectrofotometria no visível paula m. de moraes, vanessa r. loureiro e pedro m. padilha
Semina: Ciências Agrárias, 2014
Two experiments were conducted to evaluate the effect of replacing lactose with maltodextrin and ... more Two experiments were conducted to evaluate the effect of replacing lactose with maltodextrin and adding fructooligosaccharides (FOSs) to the feed of weaned piglets. The first experiment was conducted using a randomized block design with a 2 × 2 factorial arrangement (2 sources of carbohydrates: maltodextrin and lactose in the pre-starter feed and with or without the use of 0.3% FOS in the prestarter and starter feeds) with 7 repetitions in 3 animals. Performance and hematological parameters were evaluated. The second experiment was conducted using a randomized block design with a 2 × 2 × 2 + 1 factorial arrangement (2 sources of carbohydrates: maltodextrin and lactose and with or without the use of 0.3% FOS; 2 slaughter dates: 7 and 14 d post-weaning; and slaughter on the day of weaning) with 8 repetitions in 1 animal. The following parameters were evaluated: pH and relative weight of digestive organs, enzyme activity, and microbial population. In the initial phase, maltodextrin did not compromise performance and could replace lactose with economic benefits; however, it does reduce intake of the pre-starter I feed. Maltodextrin has a prebiotic effect because it reduces the total coliform and E. coli populations in the cecum and reduces the pH of the rectal contents. The use of FOSs is not justified, regardless of whether lactose or maltodextrin is added to the feed.
Ultrasonics Sonochemistry, 2013
The study is aimed to evaluate the efficiency of ultrasound-assisted extraction (UAE) as a simple... more The study is aimed to evaluate the efficiency of ultrasound-assisted extraction (UAE) as a simple strategy focused on sample preparation for metal determination in biological samples. The extraction of sodium and potassium extraction was carried out from swine feed followed by determination of the concentration of these metals by flame atomic emission spectrometry (FAES). The experiment was performed to cover the study of the variables influencing the extraction process and its optimal conditions (sample mass, particle size, acid concentration, sonication time and ultrasound power); the determination of these analytical characteristics and method validation using certified reference material; and the analysis of pre-starter diets. The optimal conditions established conditions were as follows: mass: 100 mg, particle size:<60 lm, acid concentration: 0.10 mol L À1 HCl, sonication time: 50 s and ultrasound power: 102 W. The proposed method (UAE) was applied in digestibility assays of those nutrients present in different piglet pre-starter feeds and their results proved to be compatible with those obtained from mineralized samples (P < 0.05). The ultrasound extraction method was demonstrated to be an excellent alternative for handless sampling and operational costs and the method also has the advantage of does not generating toxic residues that may negatively affect human health and contaminate the environment.
Sensing and Instrumentation for Food Quality and Safety, 2008
This paper proposes a method to determine iron in samples of fish feed and feces using ultrasound... more This paper proposes a method to determine iron in samples of fish feed and feces using ultrasound in the extraction of the analyte and in subsequent quantification by flame atomic absorption spectrometry. Using HCl 0.10 mol L-1 as the extraction solution, the optimal conditions of extraction were found to be: granulometry of the sample \60 lm; a sonication time of five cycles of 10 s and sonication power of 136 W. The method was applied in studies of the availability of iron in four food sources used in the diet of Nile Tilapia. The results obtained with the proposed extraction method allowed us to calculate the coefficients of apparent digestibility of iron in the food sources, which was not possible when using results obtained from samples mineralized by acid digestion.
Sensing and Instrumentation for Food Quality and Safety, 2008
The present work develops and optimizes a method to determine copper in samples of feces and fish... more The present work develops and optimizes a method to determine copper in samples of feces and fish feed by graphite furnace atomic absorption spectrometry (GFAAS) through the direct introduction of slurries of the samples into the spectrometer's graphite tube coated internally with metallic rhodium and tungsten carbide that acts as chemical modifiers. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (0.50% m/v of feces or feed devoid of copper) were 0.24 and 0.79 lg L-1 for the standard feces slurries and 0.26 and 0.87 lg L-1 for the standard feed slurries. The proposed method was applied in studies of absorption of copper in different fish feeds and their results proved compatible with that obtained from samples mineralized by acid digestion using microwave oven.
Journal of the Brazilian Chemical Society, 2007
Neste trabalho, um método simples, rápido e sensível, é proposto para determinação de manganês em... more Neste trabalho, um método simples, rápido e sensível, é proposto para determinação de manganês em amostras de fezes e rações de peixes por espectrometria de absorção atômica em forno de grafite (GFAAS) utilizando-se a introdução direta de suspensões das amostras no tubo de grafite. Os limites de detecção (LOD) e de quantificação (LOQ) calculados em relação a 20 leituras do branco das suspensões (0,50 % m/v de fezes ou ração isentas de manganês) foram de 28 e 92 μg kg-1 para as suspensões padrão de fezes e de 34 e 110 μg kg-1 para as suspensões padrão de ração. O método proposto foi aplicado em estudos de biodisponibilidade de manganês em diferentes amostras de rações de peixes e os resultados mostraram-se de acordo com os resultados obtidos utilizando-se amostras previamente mineralizadas por digestões ácidas em forno de microondas. This paper presents a simple, fast and sensitive method to determine manganese in samples of feces and fish feed by graphite furnace atomic absorption spectrometry (GFAAS) by the direct introduction of slurries into the graphite tube. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (0.50 % m/v of feces or feed devoid of manganese) were 28 and 92 μg kg-1 for the standard feces slurries and 34 and 110 μg kg-1 for the standard feed slurries. The proposed method was applied in bioavailability studies of manganese in different fish feeds and their results proved compatible with those obtained for samples mineralized by acid digestion using microwave oven.
Food Chemistry, 2009
... The metal determinations were carried out by FAAS using the analytical curves described in th... more ... The metal determinations were carried out by FAAS using the analytical curves described in the experimental part (item 2.4). The quantification limit (LOQ) of the analytical curve was calculated based on 10 times the standard deviation of 20 readings for the blank (Currie, 1999). ...
Food Analytical Methods, 2008
Abstract This paper presents a simple, fast, and sensitive method to determine zinc in samples of... more Abstract This paper presents a simple, fast, and sensitive method to determine zinc in samples of feces and fish feed by electrothermal atomic absorption spectrometry through the direct introduction of slurries of the samples into the spectrometer's graphite tube. The procedure is based ...
Animal Nutrition, 2016
The experiment aimed at determining the nutritional value of integral cassava root silages with y... more The experiment aimed at determining the nutritional value of integral cassava root silages with yogurt as inoculant or wastewater (manipueira) by liquid addition ensiling process. Eighteen crossbred piglets (Large White  Landrace), castrated males with an initial average weight of 50 kg were allocated in metabolism cages throughout 11-day trial duration (6 days for animal's adaptation to the cages and to the experimental diets, and 5 days of urine and faeces collection). The experimental design was a randomized block arrangement with 3 treatments and 6 replicates: basal diet (100%); mixture composed of 75% basal diet and 25% integral cassava root silage with yogurt as inoculant; a mixture composed of 75% of basal diet and 25% integral cassava root silage with wastewater. The silages with wastewater and yogurt presented the following values of apparent digestibility of dry matter 89.96% and 90.01%, apparent digestibility of crude protein of 60.67% and 66.43%, apparent digestibility of gross energy of 90.43% and 91.48%, gross energy metabolizability coefficients of 87.88% and 88.93%, digestible energy values of 3,705 and 3,783 kcal/kg on a dry matter (DM) basis, and metabolizable energy values of 3,600 and 3,676 kcal/kg DM, respectively. The results have demonstrated that integral cassava root silages with wastewater or yogurt have a high nutritional value and can be used as an alternative energy source in growing pig's diets.
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Papers by Mayra A D Saleh