RESUMO
Drinking hydrogen-rich water shows a remarkable antioxidant effect in preventive and therapeutic applications. However, there is no previous report and information on ammonia (NH3) production and duck litter quality when hydrogen water was supplied to ducks. This study verified the effects of supplying hydrogen water to ducks on NH3 production and duck litter quality in a duck rearing environment. A total of 1,200 0-d-old Pekin ducks were divided into 2 groups of similar body weight (3 replicates with 200 ducks per pen) and used for 42 days. The two groups consisted of general water and hydrogen water in the water supply system, as the control and treatment groups, respectively. There were no statistical differences between two groups for NH3 contents for the five weeks (p>0.05), except for week 6. For litter quality, no effects (p>0.05) between the two water groups were found in the pH, total nitrogen (TN), ammonia-N (VBN), and VFA content of litter. The only significant difference observed in duck litter quality was litter moisture contents (p<0.05). Lastly, mineral and heavy metal contents did not significantly differ between the two water groups. As the first pen trials evaluating the effects of hydrogen water on duck litter, these results verify that supplying hydrogen water to ducks did not influence ammonia and duck litter quality.(AU)
Assuntos
Animais , Patos/metabolismo , Patos/fisiologia , Água , Amônia , HidrogênioRESUMO
Drinking hydrogen-rich water shows a remarkable antioxidant effect in preventive and therapeutic applications. However, there is no previous report and information on ammonia (NH3) production and duck litter quality when hydrogen water was supplied to ducks. This study verified the effects of supplying hydrogen water to ducks on NH3 production and duck litter quality in a duck rearing environment. A total of 1,200 0-d-old Pekin ducks were divided into 2 groups of similar body weight (3 replicates with 200 ducks per pen) and used for 42 days. The two groups consisted of general water and hydrogen water in the water supply system, as the control and treatment groups, respectively. There were no statistical differences between two groups for NH3 contents for the five weeks (p>0.05), except for week 6. For litter quality, no effects (p>0.05) between the two water groups were found in the pH, total nitrogen (TN), ammonia-N (VBN), and VFA content of litter. The only significant difference observed in duck litter quality was litter moisture contents (p<0.05). Lastly, mineral and heavy metal contents did not significantly differ between the two water groups. As the first pen trials evaluating the effects of hydrogen water on duck litter, these results verify that supplying hydrogen water to ducks did not influence ammonia and duck litter quality.
Assuntos
Animais , Amônia , Patos/fisiologia , Patos/metabolismo , Água , HidrogênioRESUMO
The present study aimed to determine the ideal sodium levels for muscovy ducks in housing. Two hundred and forty muscovy ducks of creole lineage were used, distributed in boxes with water and food ad libitum. The experimental design was completely randomized, where treatments were constituted by six nutritional plans (initial, growth and termination) with different sodium levels, and four replicates of 10 muscovy ducks each. The birds had weekly performance evaluations, and after 90 days, eight birds (four males and four females) in each treatment were slaughtered for evaluation of carcass traits. Data collected were subjected to Tukey test at 5% of significance. Differences were observed (p 0.05) in performance (feed intake and feed conversion), where average levels of sodium presented better results. In carcass yields, average levels presented a positive influence (p 0.05) on muscovy duck growth. Male muscovy ducks presented better feed efficiency than females in the same period. The present study indicates that nutritional plan 3 (initial = 0.25%; growth = 0.30% and termination = 0.35%) showed better nutritional requirements of sodium for muscovy ducks in housing, obtaining better performance and carcass development.(AU)
Assuntos
Animais , Patos/metabolismo , Patos/fisiologia , Necessidades Nutricionais , SódioRESUMO
This research was aimed to evaluate the effect of dietary supplementation of either powdered or encapsulated probiotic on relative carcass, giblet weight and intestinal morphometry of local duck. One hundred twenty male day old duck (DOD) were distributed to 6 different dietary groups, included 2 probiotic forms of either powdered (T1) or encapsulated (T2) and 3 levels: 0% (L0), 0.2% (L1), 0.4% (L2). They were reared using pen cages for 42 days (6 weeks). Observed variables were relative carcass, giblet weight (gizzard, heart, liver) and intestinal morphometry (villus height, villus width, crypt depth). Data were analyzed by Nested of Completely Randomized Design ANOVA and if there was significant effect followed by Duncans Multiple Range Test (DMRT). The result showed that there was no significant effect (p > 0.05) of the form of either powdered or encapsulated probiotic on relative carcass, giblet weight, and intestinal morphometry. However, increasing level of probiotic have significant effect (p < 0.05) on relative carcass, villus height, and villus width, but did not significantly affect giblet weight and crypt depth. In conclusion, supplementation of either powdered or encapsulated probiotic has similar result, but it is suggested to use 0.4% of encapsulated probiotic (4 kg ton-1 of feed) in local duck diet.(AU)
Assuntos
Animais , Patos/anatomia & histologia , Patos/metabolismo , Suplementos Nutricionais/análise , Probióticos/análiseRESUMO
The present study aimed to determine the ideal sodium levels for muscovy ducks in housing. Two hundred and forty muscovy ducks of creole lineage were used, distributed in boxes with water and food ad libitum. The experimental design was completely randomized, where treatments were constituted by six nutritional plans (initial, growth and termination) with different sodium levels, and four replicates of 10 muscovy ducks each. The birds had weekly performance evaluations, and after 90 days, eight birds (four males and four females) in each treatment were slaughtered for evaluation of carcass traits. Data collected were subjected to Tukey test at 5% of significance. Differences were observed (p 0.05) in performance (feed intake and feed conversion), where average levels of sodium presented better results. In carcass yields, average levels presented a positive influence (p 0.05) on muscovy duck growth. Male muscovy ducks presented better feed efficiency than females in the same period. The present study indicates that nutritional plan 3 (initial = 0.25%; growth = 0.30% and termination = 0.35%) showed better nutritional requirements of sodium for muscovy ducks in housing, obtaining better performance and carcass development.
Assuntos
Animais , Necessidades Nutricionais , Patos/fisiologia , Patos/metabolismo , SódioRESUMO
This research was aimed to evaluate the effect of dietary supplementation of either powdered or encapsulated probiotic on relative carcass, giblet weight and intestinal morphometry of local duck. One hundred twenty male day old duck (DOD) were distributed to 6 different dietary groups, included 2 probiotic forms of either powdered (T1) or encapsulated (T2) and 3 levels: 0% (L0), 0.2% (L1), 0.4% (L2). They were reared using pen cages for 42 days (6 weeks). Observed variables were relative carcass, giblet weight (gizzard, heart, liver) and intestinal morphometry (villus height, villus width, crypt depth). Data were analyzed by Nested of Completely Randomized Design ANOVA and if there was significant effect followed by Duncans Multiple Range Test (DMRT). The result showed that there was no significant effect (p > 0.05) of the form of either powdered or encapsulated probiotic on relative carcass, giblet weight, and intestinal morphometry. However, increasing level of probiotic have significant effect (p < 0.05) on relative carcass, villus height, and villus width, but did not significantly affect giblet weight and crypt depth. In conclusion, supplementation of either powdered or encapsulated probiotic has similar result, but it is suggested to use 0.4% of encapsulated probiotic (4 kg ton-1 of feed) in local duck diet.
Assuntos
Animais , Patos/anatomia & histologia , Patos/metabolismo , Probióticos/análise , Suplementos Nutricionais/análiseRESUMO
During periods of reduced O2 supply, the most profound changes in gene expression are mediated by hypoxia-inducible factor (HIF) transcription factors that play a key role in cellular responses to low-O2 tension. Using target-enrichment sequencing, we tested whether variation in 26 genes in the HIF signaling pathway was associated with high altitude and therefore corresponding O2 availability in three duck species that colonized the Andes from ancestral low-altitude habitats in South America. We found strong support for convergent evolution in the case of two of the three duck species with the same genes (EGLN1, EPAS1), and even the same exons (exon 12, EPAS1), exhibiting extreme outliers with a high probability of directional selection in the high-altitude populations. These results mirror patterns of adaptation seen in human populations, which showed mutations in EPAS1, and transcriptional regulation differences in EGLN1, causing changes in downstream target transactivation, associated with a blunted hypoxic response.
Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Patos/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Aclimatação , Adaptação Fisiológica , Altitude , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Patos/metabolismo , Éxons , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Oxigênio/metabolismo , Seleção Genética , América do SulRESUMO
We evaluated meat quality and color of breast during storage in ducks fed diet supplemented with different forms of Houttuynia cordata (HC) with fermented red koji (FRK). In total, 240 one-day-old Pekin ducks (160 males and 80 females) were allocated to four diet treatments (control, 1% HC powder mixed with FRK, pelleted 1% HC with FRK, and coated pellets of 1% HC with FRK). At days 3 and 7 of storage, pH values were slightly influenced (p < 0.05) by different forms of HC with FRK, but was no influence at day 0 of storage day. Diet treatments with different forms of HC and FRK had an effect (p < 0.05) on TBARS values at 0, 3, and 7 days of storage and DPPH radical-scavenging activity at 0 days of storage, except for cooking loss. Overall, in breast meat of ducks, L* values at day 3 of storage and a* values at day 0 of storage were significantly influenced (p < 0.05) by treatments with different forms of HC and FRK. In conclusion, using either 1% HC and FRK pellets or pellets coated with HC and FRK at 1% resulted in a decrease in TBARS values and an increase in DPPH radical-scavenging activity during storage.(AU)
Assuntos
Animais , Carne/análise , Carne , Patos/metabolismo , Houttuynia , Fenômenos Fisiológicos da Nutrição do LactenteRESUMO
We evaluated meat quality and color of breast during storage in ducks fed diet supplemented with different forms of Houttuynia cordata (HC) with fermented red koji (FRK). In total, 240 one-day-old Pekin ducks (160 males and 80 females) were allocated to four diet treatments (control, 1% HC powder mixed with FRK, pelleted 1% HC with FRK, and coated pellets of 1% HC with FRK). At days 3 and 7 of storage, pH values were slightly influenced (p < 0.05) by different forms of HC with FRK, but was no influence at day 0 of storage day. Diet treatments with different forms of HC and FRK had an effect (p < 0.05) on TBARS values at 0, 3, and 7 days of storage and DPPH radical-scavenging activity at 0 days of storage, except for cooking loss. Overall, in breast meat of ducks, L* values at day 3 of storage and a* values at day 0 of storage were significantly influenced (p < 0.05) by treatments with different forms of HC and FRK. In conclusion, using either 1% HC and FRK pellets or pellets coated with HC and FRK at 1% resulted in a decrease in TBARS values and an increase in DPPH radical-scavenging activity during storage.
Assuntos
Animais , Carne , Carne/análise , Houttuynia , Patos/metabolismo , Fenômenos Fisiológicos da Nutrição do LactenteRESUMO
The present study evaluated the effects of aronia powder on growth performance and fatty acid profiles of ducks. A total of 90 ducks (one-day-old pekin, 48 males and 42 females) were distributed according to a completely randomized design into two treatments (control and 1% aronia powder) with 3 replicates of 15 birds per pen for 42 d. Apart from the feed:gain ratio, the other growth performance parameters, including initial body weight, final body weight, weight gain, and feed intake, did not differ significantly between treatments (p>0.05). In addition, there was no significant difference (p>0.05) in fatty acid profiles between treatments. However, oleic acid (C18:1), linoleic acid (C18:2), and polyunsaturated fatty acid (PUFA) were significantly different (p<0.05) between treatments. Our results revealed that feeding ducks with 1% aronia powder improved the weight gained and the feed:gain ratio, but did not affect the fatty acid profiles of duck breast meat.(AU)
Assuntos
Animais , Patos/crescimento & desenvolvimento , Patos/metabolismo , Ácidos Graxos/administração & dosagem , Ácidos Graxos/análiseRESUMO
Ovoinhibitor (OIH) is the main proteinase inhibitor in the egg white. In the present study, real-time quantitative PCR and Western-Blot were used to analyze different expression pattern of OIH in ovaries as a candidate gene of reproductive traits in Jingjiang ducks (JJ ducks) and Shaoxing ducks (SX ducks) during three laying stages. To study the polymorphism of the OIH gene in those two duck populations, we designed five pairs of primers to detect SNPs of exon 3-5, 5-6, 14-16 and intron 7, 9 of the OIH gene by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA pool sequencing methods. The results showed that OIH expression increased during the laying stage in the ovaries of both duck breeds. The relative expression levels of OIH in the egg at hatch and 180days of age were lower in JJ ducks than in SX ducks, but higher in JJ ducks than SX ducks at 500 days of age. Only exon 5-6 locus had a novel SNP. One variation (389G>A) was detected in the two tested duck populations and it was associated with some laying traits, such as body weight of hatch, age at first egg, weight at first egg, egg number at 72weeks of age. The AG genotype was associated with inferior body weight of hatch and superior weight at first egg, age at first egg and egg number at 72weeks of age. Therefore, these results suggest that OIH may be a strong candidate gene related to some laying traits in ducks.(AU)
Assuntos
Patos/genética , Patos/metabolismo , alfa 1-AntitripsinaRESUMO
Ovoinhibitor (OIH) is the main proteinase inhibitor in the egg white. In the present study, real-time quantitative PCR and Western-Blot were used to analyze different expression pattern of OIH in ovaries as a candidate gene of reproductive traits in Jingjiang ducks (JJ ducks) and Shaoxing ducks (SX ducks) during three laying stages. To study the polymorphism of the OIH gene in those two duck populations, we designed five pairs of primers to detect SNPs of exon 3-5, 5-6, 14-16 and intron 7, 9 of the OIH gene by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA pool sequencing methods. The results showed that OIH expression increased during the laying stage in the ovaries of both duck breeds. The relative expression levels of OIH in the egg at hatch and 180days of age were lower in JJ ducks than in SX ducks, but higher in JJ ducks than SX ducks at 500 days of age. Only exon 5-6 locus had a novel SNP. One variation (389G>A) was detected in the two tested duck populations and it was associated with some laying traits, such as body weight of hatch, age at first egg, weight at first egg, egg number at 72weeks of age. The AG genotype was associated with inferior body weight of hatch and superior weight at first egg, age at first egg and egg number at 72weeks of age. Therefore, these results suggest that OIH may be a strong candidate gene related to some laying traits in ducks.
Assuntos
Patos/genética , Patos/metabolismo , alfa 1-AntitripsinaRESUMO
The present study evaluated the effects of aronia powder on growth performance and fatty acid profiles of ducks. A total of 90 ducks (one-day-old pekin, 48 males and 42 females) were distributed according to a completely randomized design into two treatments (control and 1% aronia powder) with 3 replicates of 15 birds per pen for 42 d. Apart from the feed:gain ratio, the other growth performance parameters, including initial body weight, final body weight, weight gain, and feed intake, did not differ significantly between treatments (p>0.05). In addition, there was no significant difference (p>0.05) in fatty acid profiles between treatments. However, oleic acid (C18:1), linoleic acid (C18:2), and polyunsaturated fatty acid (PUFA) were significantly different (p<0.05) between treatments. Our results revealed that feeding ducks with 1% aronia powder improved the weight gained and the feed:gain ratio, but did not affect the fatty acid profiles of duck breast meat.
Assuntos
Animais , Patos/crescimento & desenvolvimento , Patos/metabolismo , Ácidos Graxos/administração & dosagem , Ácidos Graxos/análiseRESUMO
ABSTRACT This study evaluated the effects of aluminum chloride (AlCl3) on pH and volatile fatty acid levels in duck litter over the course of a three-week experimental period. Ninety one-day-old Pekin ducks (45 males and 45 females) were distributed into three treatments with three replicates each (10 ducks per replicate) using a completely randomized design. Two treatments were top-dressing duck litter with thin layers (1-2 cm) of 50 g or 100 g of AlCl3 per kg of litter, respectively; the control group received no litter treatment. Although no significant differences in propionic acid levels (p>0.05) were observed in any of the treatments, overall pH values for the 50 g and 100 g AlCl3 treatments were both lower (p 0.05) than those of the control group. Additionally, the two AlCl3 treatments revealed a corresponding influence (p 0.05) on acetic acid levels during the last two weeks of the experimental period. These results indicate that aluminum chloride amendments (at a suggested rate of 100 g per kg of duck litter) are potentially useful in lowering the pH of duck litter, thereby decreasing acetic acid production as an indicator of odor emissions.(AU)
Assuntos
Animais , Patos/anatomia & histologia , Patos/metabolismo , Cloretos/administração & dosagem , Cloretos/análise , Neutralizadores de OdoresRESUMO
ABSTRACT This study evaluated the effects of aluminum chloride (AlCl3) on pH and volatile fatty acid levels in duck litter over the course of a three-week experimental period. Ninety one-day-old Pekin ducks (45 males and 45 females) were distributed into three treatments with three replicates each (10 ducks per replicate) using a completely randomized design. Two treatments were top-dressing duck litter with thin layers (1-2 cm) of 50 g or 100 g of AlCl3 per kg of litter, respectively; the control group received no litter treatment. Although no significant differences in propionic acid levels (p>0.05) were observed in any of the treatments, overall pH values for the 50 g and 100 g AlCl3 treatments were both lower (p 0.05) than those of the control group. Additionally, the two AlCl3 treatments revealed a corresponding influence (p 0.05) on acetic acid levels during the last two weeks of the experimental period. These results indicate that aluminum chloride amendments (at a suggested rate of 100 g per kg of duck litter) are potentially useful in lowering the pH of duck litter, thereby decreasing acetic acid production as an indicator of odor emissions.
Assuntos
Animais , Cloretos/administração & dosagem , Cloretos/análise , Neutralizadores de Odores , Patos/anatomia & histologia , Patos/metabolismoRESUMO
Lipopolysaccharide (LPS), the major component of the outer cell wall of Gram-negative bacteria, activates the immune system and threatens the health of livestock and poultry. However, little is known about the genes and pathways involved in the immune response of ducklings to LPS. To elucidate the genes involved in the response of 7-day-old duckling spleens treated with LPS, RNA from LPS-treated and control duckling spleens was analyzed by RNA-Seq. The results showed 11,095 and 10,840 genes with >10 clean reads in the LPS-treated and control groups, respectively. Among these genes, 89 were differentially expressed (log2 ratio ≥ 1, P ≤ 0.01, false discovery rate ≤ 0.001); 67 of these were upregulated and 22 were downregulated in the LPS-treated group compared to the control. GO and GO-rich analysis showed that differentially expressed genes were enriched in 13 functional categories (P < 0.05). Pathway analysis and pathway richness analysis showed that differentially expressed genes were enriched in six pathway categories (P < 0.05). Further analysis showed that some immune system-related signaling pathways, such as the hematopoietic cell lineage, Toll-like receptor signaling pathway, T cell receptor signaling pathway, T cell receptor signaling pathway, complement and coagulation cascades, antigen processing and presentation, and chemokine signaling pathway, are active during the immune response. To confirm the RNA-Seq results, we detected CCL4, LBP, CD71, and STEAP3 expression using real-time PCR analysis, and the results were consistent with the RNA-Seq results. Our results provide new information on the genes involved in the immune response of duckling spleens to LPS.
Assuntos
Patos/genética , Patos/metabolismo , Regulação da Expressão Gênica , Lipopolissacarídeos/metabolismo , Transdução de Sinais , Baço/metabolismo , Animais , Biologia Computacional/métodos , Patos/imunologia , Perfilação da Expressão Gênica , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Imunidade/genética , Lipopolissacarídeos/imunologia , Anotação de Sequência Molecular , Reprodutibilidade dos Testes , Baço/imunologiaRESUMO
The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils and subsequently of food chains. In contaminated areas, free-range ducks used to control weeds in orchards may be exposed to CLD through polluted soil ingestion. The question arises whether they may be consumed. Muscovy ducks were raised on a guava orchard planted on a soil moderately contaminated (410 µg CLD/kg dry matter). Ducks were raised indoor up to 6 weeks of age and allowed to range freely outdoors thereafter. Twenty-nine females were sequentially slaughtered by groups of 2 to 5 ducks, after 4, 16, 19, 22 or 26 weeks spent in the orchard or after 16-17 weeks in the orchard followed by 3, 6 or 9 weeks in a closed shelter for depuration. CLD concentration increased from 258 to 1051, 96 to 278, 60 to 169 and 48 to 145 µg/kg fresh matter (FM) as the exposure through grazing increased from 4 to 22 weeks, in liver, abdominal fat and leg with and without skin, respectively. Eggs collected in the orchard contained up to 1001 µg CLD/kg FM. All these values exceeded the Maximum Residue Limit (MRL) of 20 µg/kg FM. CLD concentration in all tissues was divided by around 10 within the 9-week confinement period. Despite this quite rapid decontamination, it is estimated that 12-13 weeks would be required to achieve the MRL in liver and in eggs, and 5-6 weeks in leg muscle. Such durations would be too long in practice. Thus, the consumption of products from free-range ducks should be avoided, even in areas mildly contaminated with CLD.
Assuntos
Clordecona/metabolismo , Patos/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Inseticidas/metabolismo , Animais , Índias OcidentaisRESUMO
Several studies have documented the process of early embryonic development in poultry; however, the molecular mechanisms underlying its developmental regulation are poorly understood, particularly in ducks. In this study, we analyzed differential gene expression of embryos 6 and 25 h following oviposition to determine which genes regulate the early developmental stage in ducks. Among 216 randomly selected clones, 39 protein-encoding cDNAs that function in metabolism, transcription, transportation, proliferation/apoptosis, cell cycle, cell adhesion, and methylation were identified. Additionally, the full-length cDNA of the Nanog gene, encoding a 302-amino acid protein, was obtained. Quantitative real-time polymerase chain reaction analyses were performed to detect expression levels of the selected genes during early and late embryonic stages, which revealed that these genes are expressed in a particular spatial and temporal pattern. These results indicate that these genes may play pivotal roles in the process of area pellucida formation through a complex and precise regulatory network during development in duck embryos.
Assuntos
Patos/genética , Biblioteca Gênica , Sequência de Aminoácidos , Animais , Patos/embriologia , Patos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Dados de Sequência MolecularRESUMO
Insulin-like growth factors (IGFs) are regulators that modulate the proliferation and differentiation of muscle tissues. We quantified the messenger RNA (mRNA) expression of IGF-I, IGF-II, and type I and II IGF receptors (IGF-IR and IGF-IIR) in muscle tissues including the breast, leg, and myocardium during an early postnatal development growth stage (post-hatching weeks 1-8) in ducks. The results showed a significant age-related change in mRNA in these muscle tissues. In breast muscle, the developmental expression of IGF-I and IGF-II was highest during week 1 but decreased quickly and maintained a relatively lower level. Leg muscle had the highest mRNA expression of IGF-I and IGF-II genes at week 3. In myocardial tissues, the expression level of IGF-IR and IGF-IIR genes exhibited a "rise-decline" developmental trend. The expression patterns of IGF-I/IGF-IR and IGF-II/IGF-IIR were different between weeks 4 and 6. The same expression pattern was observed for IGF-I and IGF-IR; however, it was different from that observed for IGF-II and IGF-IIR. Our results showed a negative correlation between IGF-II mRNA expression and leg muscle weight at week 4 (P < 0.05). A negative correlation was also found between IGF-II mRNA expression and breast muscle weight (P < 0.01), and a positive correlation was found between IGF-IR expression and breast muscle weight. At week 6, a positive correlation was found between IGF-IR expression and breast muscle weight. However, at week 8, a negative correlation was found between IGF-IR expression and breast muscle weight. The results showed that the expression of IGF mRNA in duck tissues exhibits a specific developmental trend and an age-related pattern, suggesting that the regulation mechanism of these 4 genes in proliferation and differentiation of muscle tissues differed.
Assuntos
Proteínas Aviárias/genética , Patos/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Somatomedinas/genética , Animais , Proteínas Aviárias/metabolismo , Patos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Somatomedina/genética , Receptores de Somatomedina/metabolismo , Somatomedinas/metabolismo , TranscriptomaRESUMO
Reserve regulations at El Palmar State Reserve, Yucatan, Mexico, prohibit the use of lead (Pb) shot, but hunters continue to use it, and no enforcement is implemented. Pb was quantified in sediments and in blue-winged teal Anas discors. No shot pellets were found in the sediment samples, nor were differences in sediment Pb concentrations observed within the reserve between popular hunting sites and those no longer used for hunting. However, there were differences between the hunting sites and sediments from an adjacent area where hunting is prohibited. Average Pb concentrations were highest at hunting entrances (15.69 ± 18.69 mg/kg) and lowest at decoy locations (5.24 ± 4.84 mg/kg). These averages are lower than the lowest effects level (31 mg/kg), although 10 samples exceeded this level. Pb-shot prevalence in gizzards was 4.88% (n = 41). Pb levels exceeded 5.0 mg/kg dry weight in one or more of the tested tissues (liver, gizzard, and bone) in 14 (34.14%; 7 female, 7 male; 11 adult, 3 juvenile) of the total birds. Bird weight, sex, and age had no effect on Pb concentration. Hunting using Pb shot in the reserve clearly affects Pb levels in sediments and in A. discors that winter there.