Study on the Major Genes Related with Fat Deposition in Liver and Abdominal Fat of Different Breeds of Chicken

Fat deposition is higher in fast growing chickens than in slow growing chickens. The liver is the major organ for lipogenesis and fat deposition in chickens, although genetic background, age, and gender also influence fat deposition. In the present study, we aimed to explore the molecular mechanisms underlying fat deposition in liver and abdominal fat. We determined the expression abundances of the key genes regulating fat metabolism in fast-growing (FG) broilers (Cobb) and slow-growing (SG) broilers (HS1) and found that ACC, FAS, PGC-1α, PPARγ, SREBP-1c and PLIN1genes were expressed in the abdominal fat and liver tissues of FG and SG. ANOVA analysis showed that the breed, age, and tissue factors influenced the expressions of ACC, FAS, PGC-1α, PPARγ, SREBP-1c, and PLIN1 genes in the liver and abdominal fat of FG and SG. Also, the expressions of PPARγ and PLIN1 in the liver of SG were higher than that of FG. The results suggest that the differences in adipocyte development and adipose deposition between breeds are due to genetic factors.(AU)

Genome-Wide Association Study of Abdominal Fat in Wenshang Barred Chicken Based on the Slaf-Seq Technology

Chicken abdominal fat (AF) is an economically important trait, and many studies have been conducted on genetic selection for AF. However, previous studies have focused on detecting functional chromosome mutations or regions using gene chips. The present study used the specific-locus amplified fragment sequencing (SLAF-seq) technology to perform a genome-wide association study (GWAS) on purebred Wengshang Barred chicken. A total of 1,286,715 single-nucleotide polymorphisms (SNPs) were detected, and 175,211 SNPs were selected as candidate SNPs for genome-wide association analysis using TASSEL general linear models. Two SNPs markers reached genome-wide significance. Of these, rs7943847, rs127627362 were significantly associated with AF at 120 days. These SNPs are close to eight genes (SLC16A6, ARSG, WIPI1, PRKAR1A, FAM20A, ABCA8, ABCA9, CPQ,). These results would enrich the studies on AF and promote the use of Chinese chicken, especially the Wenshang Barred chicken.(AU)

Alternative Transcription of Peroxisome Proliferator-Activated Receptor Gamma in the Liver Is Associated with Fatness of Chickens

The expression of four transcription variant of peroxisome proliferator-activated receptor gamma gene (PPARG) (XM_015292931.1; XM_015292932.1; XM_015292933.1 and NM_001001460.1) in the liver of broilers was measured and its correlation with abdominal fat weight and relative abdominal fat content was investigated. The study was conducted with 92 slow-growing crossbred chickens (Cobb males x indigenous Green-legged Partridge female chickens) divided into fat and lean groups, according to their abdominal fat yield. The NM_001001460.1 transcriptwas upregulated with ratio of means 4.26 (p0.01) in the fat group in relation to the lean group. Expression of this transcript was highly correlated with relative abdominal fat content (0.71, p0.01) and abdominal fat weight (0.59, p0.01). Two SNPs are located in putative transcription factor binding sites. Mutation -991C>A disrupts PPAR while mutation -884C>T disrupts C/EBP putative binding site. The gene expression analysis of PPARg showed that the expression of the transcripts (NM_001001460.1) was more than four times higher in fat than in lean chickens. These results point out that the peroxisome proliferator-activated receptor gamma NM_001001460.1 transcript could be candidate gene for determination of abdominal fat deposition in the chickens.(AU)

Alternative Transcription of Peroxisome Proliferator-Activated Receptor Gamma in the Liver Is Associated with Fatness of Chickens

The expression of four transcription variant of peroxisome proliferator-activated receptor gamma gene (PPARG) (XM_015292931.1; XM_015292932.1; XM_015292933.1 and NM_001001460.1) in the liver of broilers was measured and its correlation with abdominal fat weight and relative abdominal fat content was investigated. The study was conducted with 92 slow-growing crossbred chickens (Cobb males x indigenous Green-legged Partridge female chickens) divided into fat and lean groups, according to their abdominal fat yield. The NM_001001460.1 transcriptwas upregulated with ratio of means 4.26 (p0.01) in the fat group in relation to the lean group. Expression of this transcript was highly correlated with relative abdominal fat content (0.71, p0.01) and abdominal fat weight (0.59, p0.01). Two SNPs are located in putative transcription factor binding sites. Mutation -991C>A disrupts PPAR while mutation -884C>T disrupts C/EBP putative binding site. The gene expression analysis of PPARg showed that the expression of the transcripts (NM_001001460.1) was more than four times higher in fat than in lean chickens. These results point out that the peroxisome proliferator-activated receptor gamma NM_001001460.1 transcript could be candidate gene for determination of abdominal fat deposition in the chickens.

A Novel Polymorphism of VLDLR Signal Peptide Coding Region and Its Association with Growth and Abdominal Fat Traits of Gaoyou Domestic Ducks

The VLDLR gene plays important roles in the growth and adiposity in humans and mice. The purpose of this study was to investigate the relationship between VLDLR gene genetic polymorphisms and growth and abdominal fat traits of the Gaoyou domestic duck. A total of 267 Gaoyou ducks were employed for testing. A 18bp deletion was identified in VLDLR signal peptide coding region. The results of c2 test suggested that the genotype frequencies of VLDLR signal peptide coding region were not in Hardy-Weinberg equilibrium. Least squares analysis showed that body weight (BW) of -18bp/-18bp genotype ducks was significantly higher than those of other genotypes from six (BW6) (p 0.05) to ten weeks of age (BW10) (p 0.01). The association analysis was performed taken body weight as covariant for abdominal percentage (AFP). Results showed that there was not interaction between genotype (p>0.05) and body weight for AFP and different genotypes had a significant effect on AFP (p 0.05). The results of Bonferroni t-test revealed that the abdominal fat percentage (AFP) of -18bp/-18bp genotype was significantly lower than those of +18bp/-18bp (p 0.05). Preliminary studies have shown that VLDLR may be a candidate gene for the selection for growth and abdominal fat, and the results of the present study indicate that VLDLR strongly influences carcass abdominal fat content of Gaoyou ducks.(AU)

A Novel Polymorphism of VLDLR Signal Peptide Coding Region and Its Association with Growth and Abdominal Fat Traits of Gaoyou Domestic Ducks

The VLDLR gene plays important roles in the growth and adiposity in humans and mice. The purpose of this study was to investigate the relationship between VLDLR gene genetic polymorphisms and growth and abdominal fat traits of the Gaoyou domestic duck. A total of 267 Gaoyou ducks were employed for testing. A 18bp deletion was identified in VLDLR signal peptide coding region. The results of c2 test suggested that the genotype frequencies of VLDLR signal peptide coding region were not in Hardy-Weinberg equilibrium. Least squares analysis showed that body weight (BW) of -18bp/-18bp genotype ducks was significantly higher than those of other genotypes from six (BW6) (p 0.05) to ten weeks of age (BW10) (p 0.01). The association analysis was performed taken body weight as covariant for abdominal percentage (AFP). Results showed that there was not interaction between genotype (p>0.05) and body weight for AFP and different genotypes had a significant effect on AFP (p 0.05). The results of Bonferroni t-test revealed that the abdominal fat percentage (AFP) of -18bp/-18bp genotype was significantly lower than those of +18bp/-18bp (p 0.05). Preliminary studies have shown that VLDLR may be a candidate gene for the selection for growth and abdominal fat, and the results of the present study indicate that VLDLR strongly influences carcass abdominal fat content of Gaoyou ducks.

Influence of Sex on the Physical-chemical Characteristics of Abdominal Chicken Fat

The aim of this study was to determine if sex influenced abdominal fat yield, chemical composition, pH, color, fatty acid profile, and stability (by Differential Scanning Calorimetry - DSC) of Cobb chickens. Abdominal fat yields of 1.86 and 1.49% were obtained for females and males, respectively. Abdominal fat lipid contents of 70.68 and 74.36 g/100g, moisture content of 27.87 and 24.09 g/100g, protein content of 0.91 and 0.95 g/100g, ash content of 0.038 and 0.041 g/100g were obtained in males and females, respectively. Fat pH was not different between sexes, with values of 6.71 for males and 6.63 for females (p 0.05). Color L* values of 58.67 and 55.42, a* values of 4.95 and 3.44, and b* values of 7.36 and 8.18 were obtained for males and females, respectively. Female abdominal fat contained higher proportion of oleic acid (53.87%) followed by palmitic acid (30.07%), whereas 34.69% palmitic acid, 31.92% oleic acid, and 25.30% linoleic acid were determined in males. The proportions of the evaluated fatty acids were significantly different (p>0.05) between males and females, except for palmitic acid. The DSC analysis showed no significant difference (p>0.05) between sexes for melting and crystallization points. It was concluded that sex influences abdominal chicken fat yield, chemical composition, color, and DSC parameters.

Influence of Sex on the Physical-chemical Characteristics of Abdominal Chicken Fat

The aim of this study was to determine if sex influenced abdominal fat yield, chemical composition, pH, color, fatty acid profile, and stability (by Differential Scanning Calorimetry - DSC) of Cobb chickens. Abdominal fat yields of 1.86 and 1.49% were obtained for females and males, respectively. Abdominal fat lipid contents of 70.68 and 74.36 g/100g, moisture content of 27.87 and 24.09 g/100g, protein content of 0.91 and 0.95 g/100g, ash content of 0.038 and 0.041 g/100g were obtained in males and females, respectively. Fat pH was not different between sexes, with values of 6.71 for males and 6.63 for females (p 0.05). Color L* values of 58.67 and 55.42, a* values of 4.95 and 3.44, and b* values of 7.36 and 8.18 were obtained for males and females, respectively. Female abdominal fat contained higher proportion of oleic acid (53.87%) followed by palmitic acid (30.07%), whereas 34.69% palmitic acid, 31.92% oleic acid, and 25.30% linoleic acid were determined in males. The proportions of the evaluated fatty acids were significantly different (p>0.05) between males and females, except for palmitic acid. The DSC analysis showed no significant difference (p>0.05) between sexes for melting and crystallization points. It was concluded that sex influences abdominal chicken fat yield, chemical composition, color, and DSC parameters. (AU)

Incorporation of labeled methionine as a tissue tracer in broiler chickens

The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose.

Incorporation of labeled methionine as a tissue tracer in broiler chickens

The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose.(AU)

Formulação de ração para frangos de corte de crescimento lento utilizando valores de energia metabolizável dos ingredientes determinada com linhagens de crescimento lento e rápido / Feed formulation for slow-growing broilers using metabolizable energy values of food determined with strains of slow-and-fast-growing

Com este trabalho, objetivou-se avaliar o efeito da formulação de rações para frangos de corte de crescimento lento, com a utilização de valores de energia metabolizável (EMAn) dos alimentos determinados por linhagens de crescimento rápido e lento, sobre o desempenho, características de carcaça, biometria de órgãos digestórios e valores energéticos das rações experimentais. Utilizaram-se 72 pintos de um dia, machos, da linhagem Isa Label, distribuídos em delineamento de blocos ao acaso, com dois tratamentos (energia dos alimentos) e seis repetições de seis animais cada. As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. Os tratamentos consistiram na formulação de rações baseadas na energia do milho e no farelo de soja determinados com frangos Cobb (EMAn Cobb) e Isa Label (EMAn Isa Label). O experimento foi conduzido na fase inicial, e as aves consumiram as dietas por 28 dias. A formulação da dieta baseada na EMAn Cobb e Isa Label não afetou o desempenho, a biometria de órgãos digestórios e as características de carcaça de aves de crescimento lento. Porém, a dieta formulada com a EMAn Isa Label resultou em melhor conversão calórica e menor deposição de gordura abdominal na carcaça das aves. EMAn da ração semelhante ao nível calculado foi determinada com a formulação baseada na EMAn do milho e do farelo de soja determinada com a linhagem Isa Label (2.750 x 2.728 kcal/kg). Os valores de EMAn do milho e do farelo de soja determinados com aves Isa Label não afetam o desempenho dos frangos de crescimento lento, porém resultam em menor gordura abdominal, atendendo aos anseios dos consumidores de aves alternativas.(AU)

We conducted this work aiming to evaluate the effect of using the metabolizable energy of food, determined by different strains (AMEn Cobb and AMEn Isa Label), on diet formulation for slow growing broilers on the performance, carcass characteristics, biometrical morphometry measures of digestive organs and energetic values of the experimental diets. A total of 72 male broiler chickens, Isa Label, were used and the experiment followed a randomized blocks design with two treatments (feedstuff energy), and six replicates of six birds each. The averages were compared by Tukey test at 5% probability. The treatments consisted in formulating diets using the energy of corn and soybean meal determined by Cobb and Isa Label strains. The experiment was conducted in the starter phase and the birds consumed the diets for 28 days. The diet formulated based on AMEn Cobb or Isa Label did not affect the performance, biometrical and morphometry measures of digestive organs and carcass characteristics. However, the diet formulated according to AMEn Isa Label resulted in better caloric conversion, bioeconomic energetic conversion and lower deposition of abdominal fat. AMEn of the diets similar to those calculated levels were determined with the formulation based on AMEn of corn and soybean meal determined for the line Isa Label (2.750 x 2.728 kcal/kg). Values of AMEn of corn and soybean meal determined with Isa Label strains not affect the performance of slow growing broilers, but resulted in lower abdominal fat according to the desires of consumers for alternative poultry.(AU)

Redução de proteína e fósforo em dietas com fitase para frangos de corte dos 22 aos 42 dias de idade / Reduction of protein and phosphorus in diets containing phytase for broilers from 22 to 42 days of age

Avaliou-se o efeito da inclusão de fitase em dietas com proteína bruta (PB) e fósforo disponível (Pd) reduzidos sobre o desempenho, rendimento de carcaça e cortes e quantidade de poluentes na cama de frangos dos 22 aos 42 dias de idade. Foram utilizados 1200 pintos aos 21 dias, média de peso inicial de 646±8g, distribuídos em blocos ao acaso em esquema fatorial 3x3+1 (três porcentagens de Pd - 0,2, 0,3 e 0,4 por cento - e três de PB - 14, 16 e 18 por cento - e um tratamento adicional, padrão) em seis repetições de 20 aves cada. A fitase (500FTU/kg) foi adicionada nas dietas com fósforo reduzido (0,2 e 0,3 por cento). Aos 42 dias as aves foram abatidas e amostras das camas foram encaminhadas para análise. Em dietas com reduzido teor de PB, melhor desempenho e rendimento de carcaça e menor quantidade de fósforo, cálcio, potássio e zinco nas camas foram obtidos com 0,3 por cento Pd+fitase. Menor quantidade de nitrogênio e potássio, porém com maior deposição de gordura abdominal e maior excreção de cobre, foram obtido com 14 por cento de PB. Comparadas ao controle, dietas com 14 por cento de PB e 0,3 por cento de Pd reduziram a excreção de fósforo em 34 por cento. Conclui-se que dietas com 14 por cento de PB e 0,3 por cento de Pd, suplementadas com fitase e aminoácidos cristalinos, podem ser utilizadas para frangos de corte dos 22 aos 42 dias.(AU)

The effect of the inclusion of phytase in reduced crude protein (CP) and available phosphorus (aP) diets on performance, carcass and cut yields and the amount of pollutant elements in the litter of broilers from 22 to 42 days of age was evaluated. One thousand and two hundred male broilers at 21 days of age, initial weight of 646±8g, were distributed in randomized block design in factorial scheme 3x3+1 (three levels of aP - 0.2, 0.3 and 0.4 percent - and three of CP - 14, 16 and 18 percent - and an additional treatment, standard) in six repetitions of 20 birds each. Phytase (500 FTU/kg) was added in reduced phosphorus (0.2 and 0.3 percent) diets. At 42 days of age, the birds were sacrificed and samples of the litters were sent to the laboratory for analysis. In reduced-CP diets, the best performance and carcass yield and lesser quantity of phosphorus, calcium, potassium and zinc in the litter was obtained with 0.3 percent aP + phytase diets. The minor quantity of nitrogen and potassium in the litter, with higher abdominal fat deposition and excretion of cupper were obtained with 14 percent CP diets. Compared to control, diets with 14 percent CP and 0.3 percent aP reduced the excretion of phosphorus in 34 percent. It was concluded that diets with 14 percent CP and 0.3 percent aP, supplemented with phytase and crystalline amino acids, can be used in broilers from 22 to 42 days old.(AU)