1. Introduction

2. Review of Existing Dog Foods

2.2. Production Process

The initial preparation for all pet food production is to select meat, vegetables, grains, and other components based on the desired recipe and nutritional requirements. Ingredients are typically inspected for quality and may undergo cleaning, and cutting or grinding processes to break down the raw ingredient into smaller size for further processes. Afterwards, treated ingredients are going to be mixed according to a specific recipe or formulation [20]. This step ensures the ingredients are evenly distributed and blended. The comprehensive production flow of various pet foods is shown on Figure 3.

The production process of dry and semi-moist dog food is similar, the ground and mixed ingredient powder need to be hydrated to a dough state by combining with water, steam, and wet ingredients before extrusion or baking. Extrusion is a cooking method where a food substance is compelled to move through a die under high temperature, pressure, and shear conditions [21]. For semi-moist dog food, the temperature and cooking time are different from dry pet food as their moisture is disparate [22]. When the dough exits the extruder, the rotary cutter slices the cooked dough into a pre-specified size and shape. The cut dry kibbles and semi-moist products are sent to air dried and cooled after cooking. However, the dry kibbles process to coating while semi-moist dog products process to packaging after extrusion or baking [23]. The dry kibbles often go into a rotating drum where they receive a uniform coating of flavor enhances to improve taste, and preservatives to extend the food’s shelf life and prevent spoilage. Subsequently, the products are going to be packed according to the specified weight and the packaging is properly sealed to avoid any potential contamination during storage and distribution [24].

Figure 3. The production process of various dog food [17,22,23].

Figure 3. The production process of various dog food [17,22,23].

The production process of wet dog food is less complex, the treated raw ingredients are directly filled into various packages such as cans, pouches, or trays after weighing and formulating. The filled products are then sealed or seamed and enter a cooking and sterilization process [20]. Once the products are cooked, they are cooled down, and then the cans are labeled. Following this, the products are going to be stored.

Ingredients for producing raw dog food are usually frozen or freeze-dried immediately after being treated and formulated. Next, the products are packed and sealed before being stored [25].

Apart from the captioned processing step for all four types of dog food, in-house quality control and assurance is also an essential step during each production procedure. A comprehensive quality management system can ensure the dog food is safe for consumption which complies with the regulations, and the consistency of the products by doing different tests including microbiological and physical tests during each production step [26]. The dog food that passes all tests should be a certified safe food for dogs and able to be distributed.

3. Hazards

3.1. Special Toxic Food

There are a lot of toxic elements that posed a risk to dogs if they are present in their food or environment. Most of the toxic food is very common to humans like chocolate, grapes and garlic. However, these food is toxic to dog. In this day and age, most of the pet owners already know that dogs cannot eat chocolate. In fact, the dose makes the poison.

Table 5. Special toxic food summary [27,28,29,30,31,32,33,34,35].

Table 5. Special toxic food summary [27,28,29,30,31,32,33,34,35].

	Poisonous Substance	Symptoms
Alcohol	Alcohol	Deaths, respiratory failures, seizures, drowsiness, losing body coordinate
Cherries	Cyanide	Deaths, breathing complications, and pupils’ dilapidation
Chocolate	Theobromine and caffeine	Seizures, high blood pressure, fast breathing, internal bleeding and fatal
Coffee and Tea	Caffeine	Vomiting, seizures, heart arrhythmias, abdominal discomfort and diarrhea
Grapes and Raisins	Grapes	Shivers, decreased appetite, lethargy, kidney failure and deaths
Nuts	Nuts	Lack of muscle control, vomiting, lethargy and seizures
Onions and Garlic	Thiosulphate	Anemia
Rhubarbs	Rhubarbs	Kidney failures and digestion complications
Xylitol	Xylitol	Loss of coordination, vomiting, and liver failures

3.2. Dog Food Safety Hazard Analysis

3.2.1. Chemical

3.2.1.1. Heavy Metals

Heavy metals are toxic substances that can harm dogs if they are consumed or exposed over a maximum tolerated dose. Exposure to toxic metals can occur in dogs through various means such as contaminated water, soil, food, or specific household objects. Several studies showed that high concentrations of toxic metals exist in different commercial pet food products while some of them such as lead (Pb), mercury (Hg), aluminum (Al), and uranium (U) are even out of the maximum tolerated level (MTL). In all samples of dog food, certain elements like antimony (Sb), barium (Ba), chromium (Cr), tin (Sn), iron (Fe), and Hg were found. The substances arsenic (As), boron (B), beryllium (Be), and selenium (Se) were found to be too low for detection in all the samples of both dog and cat foods, with a limit of 0.05mg/kg. However, some elements like Al, Pb, Cobalt (Co), Hg, U, and vanadium (V) had values higher than the limits which are shown in Table 6 [36].

In the literature data and as shown from Figure 4, Al is found in large quantities in commercial dog foods, reaching levels as high as 11,900 mg/kg of food. This is 59.1 times more than the highest allowed limit. For Hg, the detect value is much higher than the maximum tolerated level. Between the effects of excessive dosage of Hg intake, it is observed that it will lead to motor incoordination, ataxia and loss of balance while the histopathological findings demonstrated neurological injuries as well [36]. It is also crucial that they found concentrations of lead that were higher than what is considered safe for dogs and cats. The results are concerning because consuming excessive lead has been linked to signs of stomach and intestine problems, disorders in the brain and nerves, and bone marrow system, and even injuries to the kidneys [36].

In another study, from 2009 to 2019, the amount of several heavy metal detected from dog food were increased experientially (see Table 7). In 2009, 44% of the dog food samples was tested with arsenic, however, in 2019, 70% of the samples with greater amount of arsenic which is considered unsafe for a dog weighing 50 lbs., according to the World Health Organization. The amount of nickel exposure that went over the allowed limits increased from 22% in 2009 to almost 46% in 2019.

The type and severity of symptoms in dogs exposed to heavy metals can differ depending on both the metal and extent of their exposure. Various types of heavy metals can have negative impacts on different parts of dog’s body, which can result in a variety of symptoms. For instance, different heavy metals will exhibit gastrointestinal issues and neurological abnormalities which includes weakness, seizures, paralysis and tremors. Also, it will also damage their renal and hepatic function. Furthermore, some heavy metals like mercury and lead can harm the kidney and liver. The toxicity of heavy metal can impact the function or production of red blood cells which resulted in anemia. Thus, it is important to know that the symptoms can be different for each specific heavy metals, the intake dose and sensitivity of independent dog.

3.2.1.2. Sodium and Phosphorus

Excessive intake of sodium and phosphorus can have negative impacts on dogs. This is notably the case with their diet includes a significant proportion of these elements. Although sodium and phosphorus are essential mineral to dogs and play an important role in maintaining the electrolyte balance and cellular function, excessive sodium and phosphorus content can result in health issue.

According to The European Pet Food Industry Federation (FEDIAF) guidelines, all 13 wet dog foods sample contain more phosphorus than recommended for their energy intake. These energy intake levels, measured in calories per kilogram of body weight, are commonly used to calculate the daily energy needs of dogs. Out of all the foods looked at, 10 of them had too much phosphorus, which is more than double the recommended amount. Three of the diets for adult dogs had phosphorus levels higher than 4 grams per 1,000 calories, which is the maximum amount recommended for healthy adult dogs by FEDIAF (2018) [38].

From Table 8, three dog product samples contained too much phosphorus based on the upper limit set by FEDIAF, which is harmful because it can cause a condition named struvite uroliths. These uroliths can be difficult to dissolve when there is too much phosphorus in the diet [38]. It is necessary to differentiate the form of phosphorus that present when measuring its amount in foods since organic and inorganic forms have different effects on the body. The organic form of phosphorus sticks to proteins, which makes it harder for animals to absorb. On the other hand, the inorganic form of phosphorus is easier to absorb, so if there is too much of it, it can be more harmful to animals [39]. Dog will increase blood pressure, thirst and urination if they consume excessive sodium and phosphorus content. In addition, prolonged high intake will put extra stress on their heart and kidneys. Hence, dogs with kidney disease need to pay special attention that consuming less phosphorus in their diet to help slowing down the disease and make it easier for their kidney to work.

3.2.2. Biological

3.2.2.1. Bacteria

The components of raw pet food include uncooked meat, animal remains, and raw vegetables. It can be made at home or bought fresh, frozen, or freeze-dried from stores [40,41]. In recent years, many people have started to feed their dogs food that has raw meat in it. They think this is a better choice because it is more natural that without any preservatives or additives compared to regular commercial pet food [41,42]. However, raw pet food potentially consist of Salmonella, a type of bacteria that can lead to gastrointestinal illness in dogs, which can be present in dog’s food at various stages of its production, such as during ingredient sourcing or packaging and handling. Uncooked meat, eggs, or chicken used in dog food are easily contaminated with Salmonella. When dogs consume food that consist of Salmonella bacteria, the bacteria can spread in their stomach and make them sick. The severity of health effect based on the dog’s age, health condition, and the variety of Salmonella.

The most common problem caused by Salmonella infection in dogs is gastrointestinal suffering including signs like diarrhea, loss of appetite, vomiting and abdominal pain, as well as indication of restlessness and discomfort. Due to the discomfort in gastrointestinal, it will lead to dehydration to them. Dehydration leads to thirsty, dry gums, lethargy and less skin elasticity. Furthermore, when dogs are infected with Salmonella, they may get a fever that higher body temperature than normal which is usually around 38.3°C to 39.2°C may be observed as their immune system is fighting against the infection.

3.2.2.2. Mycotoxins

Mycotoxins are harmful substances that can be found in many pet foods. The major type of mycotoxins are aflatoxins, ochratoxins, and Fusarium mycotoxins. They have particular toxicity that cause adverse health effect to animal and are present in different amounts in different places. They get into the food making processes through dirty ingredients and they can slowly harm the health of animals [43]. Mycotoxins usually occur in mold or fungus and they are commonly found in crops such as corn and peanuts that have been stored in warm and humid conditions. The regional prevalence and sources in feed of mycotoxins are shown on Table 9.

Chronic adverse health effects will be occur on dogs for high dosage consumption of aflatoxin. Flavus is a type of fungus that has four different strains and they are B1, B2, G1 and G2. The most harmful substance among them is aflatoxin B1 which causes cancer and negatively affect the liver and immune system. Meanwhile, anorexia and depression are common signs of aflatoxicosis in dogs and are easily noticeable. Dogs with this condition may also experience sudden death. They usually come into contact with aflatoxins when contaminated corn is unintentionally added to their food during the process of feed production [43].

Table 10. Examples of ingredients known to be potentially contaminated with Aflatoxins [43].

Table 10. Examples of ingredients known to be potentially contaminated with Aflatoxins [43].

Examples
Cereals	Wheat, maize (corn), corn gluten feed and meal, rice, sorghum, millet, dried dostoller’s grains
Spices	Chili peppers, coriander, black pepper, ginger, tapioca, turmeric
Nuts	Brazil nuts, peanuts, sunflower, soybean, walnut, almond, pistachio, cotton seed

Dogs may exhibit various symptoms when they consume mycotoxins, which depend on the type of mycotoxin and the extent of exposure. The mycotoxin substance will affect their gastrointestinal and symptoms like diarrhea, loss of appetite, vomiting, and abdominal pain, as well as neurological signs such as disorientation, weakness, tremors, and seizures will be demonstrated. It will damage their liver like pale gums and jaundice in the worst case. Dogs may feel difficult to breathe since mycotoxin may harm their respiratory system including symptoms of coughing and sneezing.

3.2.3. Physical

Dog food contains any foreign things or chemicals that are consumed by dogs might endanger their health and well-being by posing physical hazards. These dangers might unintentionally enter dog food during the processes of production, processing, packaging or transportation. Some metal or plastic fragments originate from manufacturing related tools or machines might loose and contaminate the food by falling into or mixing with the products [44]. Moreover, if glass containers or fragments are broken during manufacturing or packaging, or if they are handled carelessly, glass particles may unintentionally contaminate dog food. If appropriate sorting and cleaning procedures are not employed, some stones, rocks or pebbles might be found in raw meat or vegetable items used in dog food. Also, if there are problems with the procurement and processing of materials, wood particles or bark may accidentally end up in dog food. Rodent droppings, insect pieces and hair can also contaminate dog food as a result of rodent or insect infestation in storage facilities. Thus, packaging materials like plastic wrap, seals or labels might wind up in the dog food and provide a health risk if they are separated or broken. When a dog is choking, they may exhibit a difficult or labor on breathing. Breathing difficulties can result from partial or total blockage of the airway caused by choking [45]. In an effort to remove the impediment, dogs may paw at their mouth or face. Choking result in anxiety and panic that show signs of agitation or anxious demeanor.

4. Existing Regulation on Dog Food Production

4.3. Adoption of HACCP and GMP Practice in Dog Food Manufacturing

There is a strong consensus among people and organizations that Hazard Analysis and Critical Control Points (HACCP) and Good Manufacturing Practices (GMP) should be utilized in the production of dog food. These are important rules and practices that help ensure the production of safe and high-quality dog food in order to comply with the aforementioned regulations from their own countries.

Dog food manufactures frequently use HACCP as a method to find and manage possible dangers in their production methods. They carefully analyze to find out any potential dangers related to the step of ingredients sourcing, packaging, storage and processing etc. By pinpointing critical control that necessitate control, they create boundaries guarantee efficient management of possible threats. Monitoring, verification procedures and corrective actions are implemented to make sure they follow the control measures [62].

Figure 5. HACCP control steps.

Figure 5. HACCP control steps.

Dog food manufacturers implement GMP to ensure the safe production and high quality of their products as GMP guidelines cover a wide range of topics including ingredient sourcing, product manufacturing, quality assurance, facility design, record keeping and cleanliness maintenance. Manufacturers follow these practices to keep their production area clean and hygienic, ensuring the good quality of ingredients, implement proper production procedures, conduct regular quality checks and comprehensive records [63].

Dog food manufacturers usually follow certain standards and guidelines, like HACCP and GMP, to meet government regulations. Pet food manufacturers must adhere to specific practices mandated by regulatory authorities in various countries to ensure the safety and quality of their products. It is important for them to follow these guidelines so they can comply with the regulations and show their commitment to produce safe dog foods.

In the Pet Food Hazard Assessment (see Table 12), the team of HACCP should evaluate each hazard based on severity likelihood matrix, which is alike the hazard assessment for human food and is beneficial to classify the significant of hazards. In the evaluation of hazard severity, critical means death and high means there is a substantial harm. Also, if there is a mild illness or no harm, it will count as medium and low severity. For the evaluation of hazard likelihood, it will classify as high, medium and low chance of occurrence [44].

4.4. Additional Quality Management Systems

There are some additional quality management systems that helps to address ingredient quality and supplier control in the production of dog foods.

By establishing a Supplier Quality Assurance Program involves implementing guidelines and procedures for evaluating and endorsing ingredient suppliers. It involves conducting regular checks on suppliers’ performance or even do site visit inspections, adherence to ingredient specifications and quality management. Manufacturers guarantee the ingredients in dog food are safe and in good quality by setting standards for their suppliers and applying appropriate testing methods to test the raw material. It involves establishing regulations for each component, specifying their required nutrients, water content, permissible bacteria levels and the presence of potentially harmful substances. Regular testing of raw materials when they arrive the factory contributes on finding any non-conformities that the manufacturer do not expected. It helps them determining whether to inform the supplier or discard any substandard ingredients. Furthermore, conducting ingredient risk assessments helps finding out possible dangers connected to certain ingredients. This includes confirming the ingredient’s origin, inspecting for harmful substances, identifying potential allergens and addressing any known safety risks. Manufacturers have the ability to enhance their ingredient selection process, modify their production methods and handle potential risks via thorough risk assessments.

Figure 6. Steps of implementing a Supplier Quality Assurance Program.

Figure 6. Steps of implementing a Supplier Quality Assurance Program.

Figure 7. Steps of implementing continous supplier performance monitoring in the production of dog foods.

Figure 7. Steps of implementing continous supplier performance monitoring in the production of dog foods.

5. Conclusion

References

1. Lee, S. Low Fertility and Policy Responses in Korea.; 2009.
2. Dog Population in Europe 2022. Available online: https://www.statista.com/statistics/515579/dog-population-europe/ (accessed on 6 September 2023).
3. Statistics | Eurostat. Available online: https://ec.europa.eu/eurostat/databrowser/view/tps00204/default/table?lang=en (accessed on 4 September 2023).
4. Number of Pet Owning Households in the United States 2023. Available online: https://www.statista.com/statistics/198095/pets-in-the-united-states-by-type-in-2008/ (accessed on 12 December 2023).
5. National Vital Statistics Reports Volume 72, Number 1 January 31, 2023.
6. Thematic Household Survey Report, No. 66.
7. Annual-Report-2022-2.Pdf.
8. Di Cerbo, A.; Morales-Medina, J.C.; Palmieri, B.; Pezzuto, F.; Cocco, R.; Flores, G.; Iannitti, T. Functional Foods in Pet Nutrition: Focus on Dogs and Cats. Research in Veterinary Science 2017, 112, 161–166. [Google Scholar] [CrossRef]
9. McConnell, A.R.; Paige Lloyd, E.; Humphrey, B.T. We Are Family: Viewing Pets as Family Members Improves Wellbeing. Anthrozoös 2019, 32, 459–470. [Google Scholar] [CrossRef]
10. Rauktis, M.E.; Rose, L.; Chen, Q.; Martone, R.; Martello, A. “Their Pets Are Loved Members of Their Family”: Animal Ownership, Food Insecurity, and the Value of Having Pet Food Available in Food Banks. Anthrozoös 2017, 30, 581–593. [Google Scholar] [CrossRef]
11. Legislative Council of the Hong Kong Special Administrative Region - Regulation of Pet Food. Available online: https://www.legco.gov.hk/research-publications/english/essentials-1516ise14-regulation-of-pet-food.htm (accessed on 5 October 2023).
12. Nutrilab, Inc. v. Schweiker, 713 F.2d 335 (1983): Case Brief Summary. Available online: https://www.quimbee.com/cases/nutrilab-inc-v-schweiker (accessed on 11 May 2023).
13. Thompson, A. Ingredients: Where Pet Food Starts. Topics in Companion Animal Medicine 2008, 23, 127–132. [Google Scholar] [CrossRef]
14. Carrión, P.; Thompson, L. Pet Food. Food Safety Management: A Practical Guide for the Food Industry, 2013; 379–396. [Google Scholar] [CrossRef]
15. Girginov, D. EVALUATION AND USE OF DOG FOODS. Trakia Journal of Sciences 2007, 5. [Google Scholar]
16. Kępińska-Pacelik, J.; Biel, W. Microbiological Hazards in Dry Dog Chews and Feeds. Animals 2021, 11, 631. [Google Scholar] [CrossRef]
17. FEDIAF | Nutritional Guidelines. Available online: https://europeanpetfood.org/self-regulation/nutritional-guidelines/ (accessed on 27 September 2023).
18. Alegría-Morán, R.A.; Guzmán-Pino, S.A.; Egaña, J.I.; Muñoz, C.; Figueroa, J. Food Preferences in Dogs: Effect of Dietary Composition and Intrinsic Variables on Diet Selection. Animals 2019, 9, 219. [Google Scholar] [CrossRef]
19. Samant, S.S.; Crandall, P.G.; Jarma Arroyo, S.E.; Seo, H.-S. Dry Pet Food Flavor Enhancers and Their Impact on Palatability: A Review. Foods 2021, 10, 2599. [Google Scholar] [CrossRef]
20. FEDIAF_How_wet_pet_food_is_made.Pdf.
21. Riaz, M.N.; Rokey, G.J. Extrusion Problems Solved: Food, Pet Food and Feed; Elsevier, 2011; ISBN 978-0-85709-520-6.
22. Siregar, J.A.; Arkoudilos, J. Semi-Moist Dog Food Preparation 1983.
23. Manual for the Manufacturing of Safe Pet Foods 2014.
24. FEDIAF_How_dry_pet_food_is_made.Pdf.
25. FEDIAF | The Safety of Pet Food. Available online: https://europeanpetfood.org/pet-food-facts/fact-sheets/quality-and-safety/the-safety-of-pet-food/ (accessed on 25 September 2023).
26. Chen, C.; Zhang, J.; Delaurentis, T. Quality Control in Food Supply Chain Management: An Analytical Model and Case Study of the Adulterated Milk Incident in China. International Journal of Production Economics 2014, 152, 188–199. [Google Scholar] [CrossRef]
27. Chocolate Poisoning In A Dog. International Journal of Veterinary Health Science & Research (IJVHSR) 2013, 1, 16–17.
28. Gwaltney-Brant, S. Chocolate Intoxication. Veterinary Medicine 2001, 96. [Google Scholar]
29. Xia, Z.; He, Y.; Yu, J. Experimental Acute Toxicity of Xylitol in Dogs. Journal of Veterinary Pharmacology and Therapeutics 2009, 32, 465–469. [Google Scholar] [CrossRef]
30. Jiang, Z.; Amartey, S.; Jiang, Z.-H.; Qin, W. D-Xylitol. In; 2012; pp. 245–263 ISBN 978-3-642-31886-3.
31. Raisin and Grape Toxicosis in Dogs - Toxicology. Available online: https://www.msdvetmanual.com/toxicology/food-hazards/raisin-and-grape-toxicosis-in-dogs (accessed on 6 December 2023).
32. Paul Pion, D.V.M.; Spadafori, G. Veterinary Partner. VIN.com 2017. [Google Scholar]
33. Onion Toxicity In Dogs: How To Spot The Symptoms | Kingsdale Animal Hospital. Available online: https://www.kingsdale.com/onion-toxicity-in-dogs-how-to-spot-the-symptoms (accessed on 6 December 2023).
34. Mak, S.L.; Au, S.L.; Tang, W.F.; Li, C.H.; Chiu, W.H.; Lee, C.C.; Wu, M.Y.T. A Critical Review on Safety of Pet Food Products. In Proceedings of the 2022 IEEE International Symposium on Product Compliance Engineering - Asia (ISPCE-ASIA); January 2022; pp. 1–5. [Google Scholar]
35. Feng, T.; Keller, L.R.; Wang, L.; Wang, Y. Product Quality Risk Perceptions and Decisions: Contaminated Pet Food and Lead-Painted Toys. Risk Analysis 2010, 30, 1572–1589. [Google Scholar] [CrossRef]
36. Zafalon, R.V.A.; Pedreira, R.S.; Vendramini, T.H.A.; Rentas, M.F.; Pedrinelli, V.; Rodrigues, R.B.A.; Risolia, L.W.; Perini, M.P.; Amaral, A.R.; de Carvalho Balieiro, J.C.; et al. Toxic Element Levels in Ingredients and Commercial Pet Foods. Scientific Reports 2021, 11, 21007. [Google Scholar] [CrossRef]
37. Atkins, P.; Restivo, T.; Lockerman, B. Heavy Metals in Pet Food: Changes in Heavy Metal Contamination in Pet Food Over the Past Decade. Spectroscopy 2021, 36, 13–23. [Google Scholar]
38. Brunetto, M.A.; Zafalon, R.V.A.; Teixeira, F.A.; Vendramini, T.H.A.; Rentas, M.F.; Pedrinelli, V.; Risolia, L.W.; Macedo, H.T. Phosphorus and Sodium Contents in Commercial Wet Foods for Dogs and Cats. Vet Med Sci 2019, 5, 494–499. [Google Scholar] [CrossRef]
39. Coltherd, J.C.; Staunton, R.; Colyer, A.; Thomas, G.; Gilham, M.; Logan, D.W.; Butterwick, R.; Watson, P. Not All Forms of Dietary Phosphorus Are Equal: An Evaluation of Postprandial Phosphorus Concentrations in the Plasma of the Cat. British Journal of Nutrition 2019, 121, 270–284. [Google Scholar] [CrossRef]
40. Freeman, L.M.; Chandler, M.L.; Hamper, B.A.; Weeth, L.P. Current Knowledge about the Risks and Benefits of Raw Meat-Based Diets for Dogs and Cats. Journal of the American Veterinary Medical Association 2013, 243, 1549–1558. [Google Scholar] [CrossRef]
41. Davies, R.H.; Lawes, J.R.; Wales, A.D. Raw Diets for Dogs and Cats: A Review, with Particular Reference to Microbiological Hazards. Journal of Small Animal Practice 2019, 60, 329–339. [Google Scholar] [CrossRef]
42. Hellgren, J.; Hästö, L.S.; Wikström, C.; Fernström, L.-L.; Hansson, I. Occurrence of Salmonella, Campylobacter, Clostridium and Enterobacteriaceae in Raw Meat-Based Diets for Dogs. Veterinary Record 2019, 184, 442–442. [Google Scholar] [CrossRef]
43. Mycotoxins in Pet Food: A Review on Worldwide Prevalence and Preventative Strategies. Available online: https://pubs.acs.org/doi/epdf/10.1021/jf062363%2B (accessed on 25 September 2023).
44. Medicine, C. for V. CVM GFI #245 Hazard Analysis and Risk-Based Preventive Controls for Food for Animals. Available online: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/cvm-gfi-245-hazard-analysis-and-risk-based-preventive-controls-food-animals (accessed on 6 December 2023).
45. Zahn, S. General First Aid for Dogs; J & J Enterprises, 1984; ISBN 978-0-912183-02-2.
46. Kopka, J. Current Challenges and Developments in GC–MS Based Metabolite Profiling Technology. Journal of Biotechnology 2006, 124, 312–322. [Google Scholar] [CrossRef]
47. Anumula, K.R. Rapid Quantitative Determination of Sialic Acids in Glycoproteins by High-Performance Liquid Chromatography with a Sensitive Fluorescence Detection. Analytical Biochemistry 1995, 230, 24–30. [Google Scholar] [CrossRef]
48. Lohmander, L.S. Analysis by High-Performance Liquid Chromatography of Radioactively Labeled Carbohydrate Components of Proteoglycans. Analytical Biochemistry 1986, 154, 75–84. [Google Scholar] [CrossRef]
49. Balachandran, P.; Friberg, M.; Vanlandingham, V.; Kozak, K.; Manolis, A.; Brevnov, M.; Crowley, E.; Bird, P.; Goins, D.; Furtado, M.R.; et al. Rapid Detection of Salmonella in Pet Food: Design and Evaluation of Integrated Methods Based on Real-Time PCR Detection. Journal of Food Protection 2012, 75, 347–352. [Google Scholar] [CrossRef]
50. Pet Food Standards | The Pet Food Industry Association of Australia.
51. PISC Technical Report 88.Pdf.
52. 国家标准|GB/T 31216-2014. Available online: https://openstd.samr.gov.cn/bzgk/gb/newGbInfo?hcno=A8758F9C4633B2CCBEE9C82CC3F4A4D1 (accessed on 24 October 2023).
53. 中国饲料工业协会宠物. Available online: http://www.chinafeed.org.cn/xwdt_10092/xhxw/202205/t20220516_403234.htm (accessed on 24 October 2023).
54. European Pet Food Industry Federation (FEDIAF). Available online: https://www.eesc.europa.eu/en/policies/policy-areas/enterprise/database-self-and-co-regulation-initiatives/132 (accessed on 25 October 2023).
55. 10_GAPFA_Factsheet_How_pet_food_is_regulated.Pdf.
56. Sugiura, K.; Fujii, T.; Onodera, T. Introduction of a Pet Food Safety Law in Japan. Veterinaria italiana 2009, 45, 297–303. [Google Scholar]
57. Safety of Feeds and Pet Foods : MAFF. Available online: https://www.maff.go.jp/e/policies/ap_health/petfood/ (accessed on 26 October 2023).
58. 一般社団法人ペットフード協会. Available online: https://petfood.or.jp/index.html (accessed on 26 October 2023).
59. Animal Protection Act (2017). | FAOLEX. Available online: https://www.fao.org/faolex/results/details/en/c/LEX-FAOC040369 (accessed on 25 October 2023).
60. R.O.C.(Taiwan), M. of A., Executive Yuan Ministry of Agriculture, Executive Yuan, R.O.C.(Taiwan). Available online: https://eng.moa.gov.tw/ws.php?id=2505344 (accessed on 26 October 2023).
61. The Association of American Feed Control Officials. Available online: https://www.aafco.org/ (accessed on 24 October 2023).
62. Saskatoon-Based Raw Pet Food Manufacturer, Spring Meadows Natural Pet Food, Receives HACCP Canada Certification. NASDAQ OMX’s News Release Distribution Channel, 2018.
63. Institute of Food Science and Technology; Louise Manning Food and Drink - Good Manufacturing Practice : A Guide to Its Responsible Management; Wiley-Blackwell: Chichester, West Sussex, UK, 2013; Vol. 6th ed; ISBN 978-1-118-31820-1.
64. Lee, J.M.; Jang, M.A. The Current Status of the Companion Animal products and Pet Cosmetics industry. The Journal of the Convergence on Culture Technology 2021, 7, 833–844. [Google Scholar] [CrossRef]
65. Tansakul, N.; Trongvanichnam, K.; Udomkusonsri, P.; Limsuwan, S. A Survey of Aflatoxins and Ochratoxin A Contamination in Pet Food in Thailand. Journal of Mahanakorn Veterinary Medicine 2014, 9, 1–9. [Google Scholar]
66. Jeong, W.-I.; Do, S.-H.; Jeong, D.; Chung, J.; Yang, H.; Yuan, D.; Hong, I.; Park, J.-K.; Goo, M.; Jeong, K.-S. Canine Renal Failure Syndrome in Three Dogs. Journal of veterinary science 2006, 7, 299–301. [Google Scholar] [CrossRef]
67. 80% of Complete Canned Dog Food Failed to Meet Internationally Recommended Levels for Micronutrients and Amino Acids Negligence of Labelling and Misfeeding May Cause Health Risks | Consumer Council. Available online: https://www.consumer.org.hk/en/press-release/534-canned-pouched-pet-food-for-dogs (accessed on 12 December 2023).