We developed a novel approach to determine rotenone residues in foodstuffs, by integrating solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC-MS/MS) technologies, to achieve high s...We developed a novel approach to determine rotenone residues in foodstuffs, by integrating solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC-MS/MS) technologies, to achieve high sensitivity and selectivity. In our method, the solvent extraction with n-hexane-dichloromethane (50:50, v/v) and cleanup with florisil SPE cartridges using ethyl acetate-ethyl ether (25:75, v/v) as eluents provided adequate recovery of rotenone. The detection of rotenone was then carried out by LC-MS/MS using acetonitrile-water with the 0.1% formic acid (w/v) as the mobile phase. The multiple reaction monitoring (MRM) scheme employed in the approach involved the transitions of the precursor ion to three selected product ions, in which one pair for quantification was m/z 395.3 〉 213.2 and the other two pairs for identification were m/z 395.3 〉 192.2 and 395.3 〉 367.0. The limits of quantification (LOQs) of the method ranged from 0.001 to 0.005 mg kg-1 depending on the matrix. Intra- and inter-day precisions (relative standard deviations, RSDs) for rotenone were less than 7.1 and 14.8%, respectively. Results from repetitive analysis suggested good reproducibility of the method for rotenone residue detection. The recoveries at three concentrations (LOQ, 10LOQ and 100LOQ) ranged from 79.3-118.3% in cabbage, potato, onion, carrot, apple, orange, banana, lichee, tea, and Shiitake mushroom. The proposed procedure was then applied to the analysis of 129 real samples collected from Xiamen, Fujian Province, China. The existence of rotenone was found in two tea products with concentrations of 0.012 and 0.016 mg kg-1, respectively. The method has great potential for routine analysis of monitoring rotenone residue in foodstuffs.展开更多
An effective method for the trace analysis of indoxacarb residue in foodstuffs of plant and animal origin [grapefruit, ginger, fresh soybean, bamboo shoot, qing-gen-cai (cruciferous vegetable), chicken, fish, and po...An effective method for the trace analysis of indoxacarb residue in foodstuffs of plant and animal origin [grapefruit, ginger, fresh soybean, bamboo shoot, qing-gen-cai (cruciferous vegetable), chicken, fish, and pork] was developed using gas chromatography (GC-ECD) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Samples were extracted using acetone and n-hexane mixed solvent (1:2, v/v) and then purified using solid-phase extraction (SPE) columns. The extracts were analyzed using GC-ECD and LC-MS/MS. The multiple reaction monitoring (MRM) scheme used involved transitions of the precursor ions to selected two product ions in which one pair for identification was m/z 529 → 293 and another pair for quantification was m/z 529 → 249. The detection limits (LODs) of the method were 0.0015 and 0.0006 mg kg^-1, and the quantification limits (LOQs) were 0.005 and 0.002 mg kg^-1 for GC-ECD and LC-MS/MS, respectively. The relative standard deviations (RSDs) of recovery for indoxacarb were lower than 15% in 10 types of agro-products. Ten repetitive determinations of recovery achieved good reproducibility for indoxacarb and the recovery ranged from 72.08 to 113.74%. The proposed procedure was applied to the analysis of several real samples of different origin from Fujian Province, China, and 299 samples were screened for indoxacarb residue, of which 5 positive samples were found.展开更多
Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper start...Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security展开更多
There is still no effective means to analyze in depth and utilize domestic mass data about agricultural product quality safety tests in china now. The neural network algorithm, the classification regression tree algor...There is still no effective means to analyze in depth and utilize domestic mass data about agricultural product quality safety tests in china now. The neural network algorithm, the classification regression tree algorithm, the Bayesian network algorithm were selected according to the principle of selecting combination model and were used to build models respectively and then combined, innovatively establishing a combination model which has relatively high precision, strong robustness and better explanatory to predict the results of perishable food transportation meta-morphism monitoring. The relative optimal prediction model of the perishable food transportation metamorphism monitoring system could be got. The relative perfect prediction model can guide the actual sampling work about food quality and safety by prognosticating the occurrence of unqualified food to select the typical and effective samples for test, thus improving the efficiency and effectiveness of sampling work effectively, so as to avoid deteriorated perishable food’s approaching the market to ensure the quality and safety of perishable food transportation. A solid protective wall was built in the protection of general perishable food consumers’ health.展开更多
Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiologi...Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiological level, fungal and mycotoxin contaminations of local foodstuffs in Cixian County were analyzed using classical fungal culture methods and HPLC. From 1990 to 1994, 220 corn/wheat samples and 34 corn samples were studied. As a control, 26 corn samples collected from a relatively low incidence area of Eca in Zanhuang County were analyzed for mycotoxins in 1990. The results showed that fungal contamination in corn and wheat was severe and that several of the predominant contaminating fungi such as Furasium moniliforme, etc. were carcinogenic. HPLC results showed that the detection rate and mean content of the mycotoxin sterigmatocystin (ST) in the mountainous area (5/8; 9. 14 μg/kg) were significantly higher than those in the hilly (0; 0) and plain areas (1/18; 1. 29 μg/kg) as well as in low risk area control samples (3/26; 0. 76 μg/kg). Detection rates of deoxynivalenol (DON) in mountainous and hilly areas (5/8, 4/8 respectively) were slightly higher than that in plain area (8/18), while the mean content of DON in the plain area was significantly higher (90. 45-170. 22 vs 50. 56 and 46. 45 μg/kg).Among the different aflatoxins, AFB1 was detected in samples from the two villages in the plain area for the subsequent two years. The mean content of AFB1 was 0. 0183μg/kg, and the highest level was 0. 0497 μg/kg. No AFB1 was detected in the samples from mountainous and hilly areas. AFG1 was detected in more than half of all the samples, and its concentration ranged from 8. 77 to 46. 51 ng/kg. No AFG2 was found in the samples. Thus, the results suggest that at present, fungal and mycotoxin contamination of foodstuffs in Cixian County are quite common.展开更多
The system of State Foodstuff Security is a comprehensively systematical framework, which needs concerted support and energetic cooperation from all walks of lives. This paper analyzes the strategies for State Foodstu...The system of State Foodstuff Security is a comprehensively systematical framework, which needs concerted support and energetic cooperation from all walks of lives. This paper analyzes the strategies for State Foodstuff Security: integrating new biological techniques with traditional methods, full utilization of soil with its protection, policies leading with market regulation, steady high yield with promoting additional value through further processing, general foodstuff production with substitute food seeking, domestic self-supply with international trade complementarities as well as short-term exploiting with long-term development on the basis of the increase of general foodstuff production capability.展开更多
The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using ...The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using γ-ray spectroscopy. Another group of hay, water, and soil samples from the same location were also analyzed. Hay samples were found to contain the highest radioactivity concentration among all the samples that were investigated. This in- crement could be due to the high water content in the shoots which tends to accumulate soluble radionuclides. The average calculated concentrations of soil samples in the present study exhibits the lowest values with respect to those from different countries. In the case of water samples, the average activities of both 232Th and 40K were similar to those for soil while 226Ra was twice that of water sample. The annual ingestion dose from each radionuclide was cal- culated. The computed annual dose owing to daily intake of radium, thorium, and potassium via wheat flour, lentils, and bean in the present study (214.8 μSv) is ten times lower than the global average annual radiation dose (2400 μSv) from the natural radiation sources as proposed by UNSCEAR. The obtained results show that the dose values are quite low and carry insignificant radiation dose to the public.展开更多
Based on a survey carried out on all fully certificated foodstuff manufacturers in Guangzhou, an analysis of the status quo of Foodstuff Processing Standardization in Guangzhou is made to identify the major problems a...Based on a survey carried out on all fully certificated foodstuff manufacturers in Guangzhou, an analysis of the status quo of Foodstuff Processing Standardization in Guangzhou is made to identify the major problems and measures to be adopted for improvement.展开更多
Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an imag...Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an image analysis. Molecular techniques employing 16S and 28S rDNA profiles generated by PCR-DGGE were used to detect the variation in microbial community (bacteria, fungi) of Pangasius fish from Viet Nam harvested in different aquaculture farms and during different seasons and Shea tree fruits from five different districts in Mali. The bacterial DNA profiles from Pangasius fish and the fungal DNA profile from Shea tree fruits were specific to each place of production and could be used as a biological bar code certifying the origin of fish and fruit. To follow the product during processing, the authors proposed to identify and validate some pertinent biological markers which come from the environment of the food to assure their traceability during international trade. It is new analytical method which permits to determine the origin of food or to follow them during international trade.展开更多
Zhejiang, situated in the Yangtze delta and neighbouring Shanghai, is widely known for fish and rice production. The Zhejiang Provincial Cereals, Oils and Foodstuffs I/E Co. Ltd. formerly Zhejiang provincial Cereals, ...Zhejiang, situated in the Yangtze delta and neighbouring Shanghai, is widely known for fish and rice production. The Zhejiang Provincial Cereals, Oils and Foodstuffs I/E Co. Ltd. formerly Zhejiang provincial Cereals, Oils and Foodstuffs I/E Company, is one of the largest foreign trade shareholding enterprises in Zhejiang Province. It展开更多
Evaluation of radionuclide concentrations in foodstuffs is of great concern owing to the potential radiological hazards to human health. This study was carried out to assess the radionuclide concentrations of ^40K, ^1...Evaluation of radionuclide concentrations in foodstuffs is of great concern owing to the potential radiological hazards to human health. This study was carried out to assess the radionuclide concentrations of ^40K, ^134Cs, ^137Cs, ^131I, ^90Sr, ^239pu, in selected foodstuffs, in order to assess the effects of the elevated levels of radionuclides concentration in environmental media after the FDNPS (Fukushima Daiichi Nuclear Power Station) accident on imported food. HPGe (high purity germanium) detector based spectrometry system coupled with multi-channel analyzer was used for the assessment. The mean concentrations of ^40K, ^134Cs, ^137Cs, ^131I, ^90Sr, ^239pu, were found to be 50.1 ± 2.44 Bq/Kg, 109.6 ± 0.141 Bq/Kg, 134.2 ± 0.027 Bq/Kg, 2.57 ± 0.019 Bq/Kg, 0.59 ± 0.03 Bq/Kg, 0.160 ± 0.033 Bq/Kg, and 0.227 ± 0.021 Bq/Kg respectively. The analysis showed that the radioactivity levels of ^241Am, ^134Cs and ^137Cs were found to be relatively low and within the acceptable levels.展开更多
Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synth...Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.展开更多
基金supported by the Fujian Provincial Department of Science and Technology, China(2006F3002)Xiamen Science and Technology Bureau,China (3502Z20072003, 3502Z20092008 and3502Z20092009)Ministry of Agriculture,China (200903034)
文摘We developed a novel approach to determine rotenone residues in foodstuffs, by integrating solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC-MS/MS) technologies, to achieve high sensitivity and selectivity. In our method, the solvent extraction with n-hexane-dichloromethane (50:50, v/v) and cleanup with florisil SPE cartridges using ethyl acetate-ethyl ether (25:75, v/v) as eluents provided adequate recovery of rotenone. The detection of rotenone was then carried out by LC-MS/MS using acetonitrile-water with the 0.1% formic acid (w/v) as the mobile phase. The multiple reaction monitoring (MRM) scheme employed in the approach involved the transitions of the precursor ion to three selected product ions, in which one pair for quantification was m/z 395.3 〉 213.2 and the other two pairs for identification were m/z 395.3 〉 192.2 and 395.3 〉 367.0. The limits of quantification (LOQs) of the method ranged from 0.001 to 0.005 mg kg-1 depending on the matrix. Intra- and inter-day precisions (relative standard deviations, RSDs) for rotenone were less than 7.1 and 14.8%, respectively. Results from repetitive analysis suggested good reproducibility of the method for rotenone residue detection. The recoveries at three concentrations (LOQ, 10LOQ and 100LOQ) ranged from 79.3-118.3% in cabbage, potato, onion, carrot, apple, orange, banana, lichee, tea, and Shiitake mushroom. The proposed procedure was then applied to the analysis of 129 real samples collected from Xiamen, Fujian Province, China. The existence of rotenone was found in two tea products with concentrations of 0.012 and 0.016 mg kg-1, respectively. The method has great potential for routine analysis of monitoring rotenone residue in foodstuffs.
基金grants from Fujian Pro- vincial Department of Science and Technology (2006F3002)Xiamen Science and Technology Bureau (3502Z20072003)China Postdoctoral Programme (20060390291)
文摘An effective method for the trace analysis of indoxacarb residue in foodstuffs of plant and animal origin [grapefruit, ginger, fresh soybean, bamboo shoot, qing-gen-cai (cruciferous vegetable), chicken, fish, and pork] was developed using gas chromatography (GC-ECD) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Samples were extracted using acetone and n-hexane mixed solvent (1:2, v/v) and then purified using solid-phase extraction (SPE) columns. The extracts were analyzed using GC-ECD and LC-MS/MS. The multiple reaction monitoring (MRM) scheme used involved transitions of the precursor ions to selected two product ions in which one pair for identification was m/z 529 → 293 and another pair for quantification was m/z 529 → 249. The detection limits (LODs) of the method were 0.0015 and 0.0006 mg kg^-1, and the quantification limits (LOQs) were 0.005 and 0.002 mg kg^-1 for GC-ECD and LC-MS/MS, respectively. The relative standard deviations (RSDs) of recovery for indoxacarb were lower than 15% in 10 types of agro-products. Ten repetitive determinations of recovery achieved good reproducibility for indoxacarb and the recovery ranged from 72.08 to 113.74%. The proposed procedure was applied to the analysis of several real samples of different origin from Fujian Province, China, and 299 samples were screened for indoxacarb residue, of which 5 positive samples were found.
基金Supported by the Achievement of Program for New Century Excellent Talents in Heilongjiang Province (1153-NCET-004)Project of Postdoctoral Scientific Research Launch Foundation in Heilongjiang Province
文摘Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security
文摘There is still no effective means to analyze in depth and utilize domestic mass data about agricultural product quality safety tests in china now. The neural network algorithm, the classification regression tree algorithm, the Bayesian network algorithm were selected according to the principle of selecting combination model and were used to build models respectively and then combined, innovatively establishing a combination model which has relatively high precision, strong robustness and better explanatory to predict the results of perishable food transportation meta-morphism monitoring. The relative optimal prediction model of the perishable food transportation metamorphism monitoring system could be got. The relative perfect prediction model can guide the actual sampling work about food quality and safety by prognosticating the occurrence of unqualified food to select the typical and effective samples for test, thus improving the efficiency and effectiveness of sampling work effectively, so as to avoid deteriorated perishable food’s approaching the market to ensure the quality and safety of perishable food transportation. A solid protective wall was built in the protection of general perishable food consumers’ health.
文摘Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiological level, fungal and mycotoxin contaminations of local foodstuffs in Cixian County were analyzed using classical fungal culture methods and HPLC. From 1990 to 1994, 220 corn/wheat samples and 34 corn samples were studied. As a control, 26 corn samples collected from a relatively low incidence area of Eca in Zanhuang County were analyzed for mycotoxins in 1990. The results showed that fungal contamination in corn and wheat was severe and that several of the predominant contaminating fungi such as Furasium moniliforme, etc. were carcinogenic. HPLC results showed that the detection rate and mean content of the mycotoxin sterigmatocystin (ST) in the mountainous area (5/8; 9. 14 μg/kg) were significantly higher than those in the hilly (0; 0) and plain areas (1/18; 1. 29 μg/kg) as well as in low risk area control samples (3/26; 0. 76 μg/kg). Detection rates of deoxynivalenol (DON) in mountainous and hilly areas (5/8, 4/8 respectively) were slightly higher than that in plain area (8/18), while the mean content of DON in the plain area was significantly higher (90. 45-170. 22 vs 50. 56 and 46. 45 μg/kg).Among the different aflatoxins, AFB1 was detected in samples from the two villages in the plain area for the subsequent two years. The mean content of AFB1 was 0. 0183μg/kg, and the highest level was 0. 0497 μg/kg. No AFB1 was detected in the samples from mountainous and hilly areas. AFG1 was detected in more than half of all the samples, and its concentration ranged from 8. 77 to 46. 51 ng/kg. No AFG2 was found in the samples. Thus, the results suggest that at present, fungal and mycotoxin contamination of foodstuffs in Cixian County are quite common.
文摘The system of State Foodstuff Security is a comprehensively systematical framework, which needs concerted support and energetic cooperation from all walks of lives. This paper analyzes the strategies for State Foodstuff Security: integrating new biological techniques with traditional methods, full utilization of soil with its protection, policies leading with market regulation, steady high yield with promoting additional value through further processing, general foodstuff production with substitute food seeking, domestic self-supply with international trade complementarities as well as short-term exploiting with long-term development on the basis of the increase of general foodstuff production capability.
文摘The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using γ-ray spectroscopy. Another group of hay, water, and soil samples from the same location were also analyzed. Hay samples were found to contain the highest radioactivity concentration among all the samples that were investigated. This in- crement could be due to the high water content in the shoots which tends to accumulate soluble radionuclides. The average calculated concentrations of soil samples in the present study exhibits the lowest values with respect to those from different countries. In the case of water samples, the average activities of both 232Th and 40K were similar to those for soil while 226Ra was twice that of water sample. The annual ingestion dose from each radionuclide was cal- culated. The computed annual dose owing to daily intake of radium, thorium, and potassium via wheat flour, lentils, and bean in the present study (214.8 μSv) is ten times lower than the global average annual radiation dose (2400 μSv) from the natural radiation sources as proposed by UNSCEAR. The obtained results show that the dose values are quite low and carry insignificant radiation dose to the public.
文摘Based on a survey carried out on all fully certificated foodstuff manufacturers in Guangzhou, an analysis of the status quo of Foodstuff Processing Standardization in Guangzhou is made to identify the major problems and measures to be adopted for improvement.
文摘Abstract: One of the great concerns of the customers is the traceability of the products. The authors proposed to link microbial ecology to geographical origin of foodstuffs by a molecular technique joined to an image analysis. Molecular techniques employing 16S and 28S rDNA profiles generated by PCR-DGGE were used to detect the variation in microbial community (bacteria, fungi) of Pangasius fish from Viet Nam harvested in different aquaculture farms and during different seasons and Shea tree fruits from five different districts in Mali. The bacterial DNA profiles from Pangasius fish and the fungal DNA profile from Shea tree fruits were specific to each place of production and could be used as a biological bar code certifying the origin of fish and fruit. To follow the product during processing, the authors proposed to identify and validate some pertinent biological markers which come from the environment of the food to assure their traceability during international trade. It is new analytical method which permits to determine the origin of food or to follow them during international trade.
文摘Zhejiang, situated in the Yangtze delta and neighbouring Shanghai, is widely known for fish and rice production. The Zhejiang Provincial Cereals, Oils and Foodstuffs I/E Co. Ltd. formerly Zhejiang provincial Cereals, Oils and Foodstuffs I/E Company, is one of the largest foreign trade shareholding enterprises in Zhejiang Province. It
文摘Evaluation of radionuclide concentrations in foodstuffs is of great concern owing to the potential radiological hazards to human health. This study was carried out to assess the radionuclide concentrations of ^40K, ^134Cs, ^137Cs, ^131I, ^90Sr, ^239pu, in selected foodstuffs, in order to assess the effects of the elevated levels of radionuclides concentration in environmental media after the FDNPS (Fukushima Daiichi Nuclear Power Station) accident on imported food. HPGe (high purity germanium) detector based spectrometry system coupled with multi-channel analyzer was used for the assessment. The mean concentrations of ^40K, ^134Cs, ^137Cs, ^131I, ^90Sr, ^239pu, were found to be 50.1 ± 2.44 Bq/Kg, 109.6 ± 0.141 Bq/Kg, 134.2 ± 0.027 Bq/Kg, 2.57 ± 0.019 Bq/Kg, 0.59 ± 0.03 Bq/Kg, 0.160 ± 0.033 Bq/Kg, and 0.227 ± 0.021 Bq/Kg respectively. The analysis showed that the radioactivity levels of ^241Am, ^134Cs and ^137Cs were found to be relatively low and within the acceptable levels.
基金This work was supported by Texas A&M AgriLife Research(H-8200).
文摘Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.