Understanding regulations affecting pet foods

In the United States, pet foods are subject to regulation at both the federal and the state levels. The US Food and Drug Administration has jurisdiction over all animal feeds (including pet foods, treats, chews, supplements, and ingredients) in interstate commerce, which includes imported products. Many states adopt and enforce at least in part the Association of American Feed Control Officials Model Bill and Model Regulations for Pet Food and Specialty Pet Food. Thus, all pet foods in multi-state distribution are subject to a host of labeling requirements covering aspects such as product names, ingredient lists, nutrient content guarantees, and nutritional adequacy statements. Ingredients must be GRAS (generally recognized as safe) substances, approved food additives, or defined by Association of American Feed Control Officials for their intended use. Pet food labels may not bear claims that are false or misleading or that state or imply use for the treatment or prevention of disease. Pet foods that are found to be adulterated or misbranded may be subject to seizure or other enforcement actions.     

Evaluation of practical dry dog foods suitable for all life stages

We evaluated the nutritional adequacy of 2 dry-type commercially prepared dog diets by use of a gestation/lactation/growth protocol outlined by the Association of American Feed Control Officials. Both diets were formulated to contain minimal concentrations of nutrients, compared with canine nutrient requirements listed in the 1974 or 1985 National Research Council publications. Although there were no significant differences in the performance of dogs fed either diet, only one of the diets (diet 2) passed the complete life-stage protocol test. The nutritional profile of diet 1 was only sufficient to support a claim of complete and balanced nutrition for adult maintenance. Any commercial dry dog food meeting the nutrient levels in diet 2, and of similar nutrient bioavailability, should also pass an Association of American Feed Control Officials complete life-stage protocol test.     

Equations used to develop commercial dog food feeding guidelines and Canadian owner feeding practices in 2018

Feeding guidelines on commercial dog food packages provide a suggested starting point for food provision for dogs. The equations used to develop commercial dog food feeding guidelines and the owner feeding practices surveyed were examined in this study. The equations used to develop feeding guidelines and the energy density calculation method (Traditional Atwater or Modified Atwater equation) were investigated for 200 dry dog foods sold in Canada. Not all energy densities of products were calculated using the modified Atwater equation, a requirement if claiming compliance with the Association of American Feed Control Officials (AAFCO). Commercial feeding guidelines provide conservative estimates of pet dog energy needs. A survey of dog owners’ feeding practices was conducted, with 739 responses analyzed. Respondents generally took appropriate action to manage the weight of their dogs through both exercise and dietary management. Further investigation should explore how owners may be successfully managing their dogs’ weight without veterinary supervision.     

Availability, brands, labelling and salmonella contamination of raw pet food in the minneapolis/st. Paul area

The purpose of the study was to characterize the commercially available raw meat pet food diets in the Minneapolis/St. Paul area by (i) determining the number and types of available diets; (ii) assessing pet food stores and brand labels for the provision of precautionary statements regarding the risk of foodborne illness from raw meat; (ii) assessing the labels for Food and Drug Administration (FDA)/American Association of Feed Control Officials (AAFCO) required content and nutrient-related information; and (iv) culturing purchased diets for the presence of Salmonella. Sixty raw meat diets were purchased, representing 11 different brands from eight different stores. Diets were readily available in the form of raw-frozen, dehydrated or freeze-dried varieties from different protein sources, such as lamb, beef, chicken or duck. All stores promoted raw meat diets; however, none provided foodborne illness warnings. Brands varied greatly in their precautionary statements; none of the diets underwent feeding trials; and nutritional adequacy substantiation was through formulation only. The first five ingredients tended to consist of meat, organ meat (by-products), vegetables, grains and ground bones. Currently, it is required that pet foods have an AAFCO nutritional adequacy statement and provide a guaranteed analysis table. Three brands did not meet these FDA requirements. Thirty-one (51.7%) of the 60 raw meat diets underwent some degree of processing including dehydration, freeze-drying or high-pressure pasteurization. Four of the 60 raw diets (7%) tested positive for Salmonella. Analysis of raw meat pet food labels indicated a lack of foodborne illness warnings. Based on these findings, we recommend that warning statements similar to those required by the United States Department of Agriculture and placed on labels of raw meat intended for human consumption be provided on the labels of raw meat pet food diets.     

Evaluation of dietary patterns in dogs with cardiac disease

OBJECTIVE: To determine the dietary patterns and intake of nutrients of concern in dogs with cardiac disease. DESIGN: Prospective study. ANIMALS: 82 dogs with dilated cardiomyopathy (DCM) or chronic valvular disease. PROCEDURE: Owners of dogs were contacted and given a standardized telephone questionnaire regarding diet and a 24-hour food recall to determine daily intake of calories, protein, fat, sodium, potassium, and magnesium. RESULTS: Among the 82 dogs, 71% had no congestive heart failure (CHF), and 29% had CHF or a history of CHF. Sixty-one percent of dogs had concurrent diseases. Anorexia was or had been evident in 34% of dogs and was significantly more common in the CHF group and in dogs with DCM. Most dogs (92%) received some treats and table food, with a median percentage of daily calories from treats of 19% (range, 0% to 100%). Most owners (57%) that administered pills used human or pet foods for pill administration. Most dogs ate more than the Association of American Feed Control Officials (AAFCO) minimum values for fat and protein. Daily sodium intake varied from 14 to 384 mg/100 kcal, compared with the AAFCO minimum of 17 mg/100 kcal. A median of 25% of total daily sodium came from treats and table food (range, 0% to 100%). Dogs with CHF ate significantly more sodium, compared with dogs with no CHF. CONCLUSIONS AND CLINICAL RELEVANCE: Dietary intake for dogs with cardiac disease is highly variable and often not optimal.     

The effect of crude fibre on apparent digestibility and digestible energy content of extruded dog foods

The apparent digestibility of nutrients and energy of 38 commercial dry extruded dog foods was measured using six adult (2 to 3 year-old) female Beagles. Diets contained [in g/kg dry matter (DM)]: 164–360 crude protein (CP); 79–261 ether extracts (EE); 8–33 crude fibre (CF) and 318–585 nitrogen free extracts (NFE). Apparent energy digestibility ranged from 77.3 to 91.6%, and was closely related to CF content ( r =–0.85), yielding the resultant equation: GED (%)=94.00 – 4.04 × CF (% DM). The estimation of digestible energy content of foods from digestibility coefficients predicted from the above equation and gross energy measured or estimated from the Weende fractions, provides a more accurate prediction of experimental values than the Atwater approach followed by the National Research Council and the Association of American Feed Control Officials.     

Determining metabolizable energy content in commercial pet foods

This study was conducted to assess the suitability of several equations for the estimation of metabolizable energy (ME) of pet foods. Sixteen canned and 31 dry cat foods and 24 dry dog foods representing the range of energy densities found in commercial adult, growth or all life stage products were evaluated in four separate experiments. In vivo ME was compared with estimates of ME generated by several previously published equations. The results indicated that the equation recommended by Association of American Feed Control Officials provided reasonable estimates of in vivo ME for both canned cat foods and dry dog foods, but proved unsuitable for dry cat foods. Better estimates were generated in each case using other published equations. Of the equations tested, the most accurate equations for estimating ME (kJ/g) without feeding trials were:
for canned cat foods: [(16.32 × protein) + (32.22 × fat) + (12.55 × NFE)];
for dry cat foods: [((GE × 1.209) – 1.911) × 4.184] or [((0.075 × g fat) + 2.766) × 4.184]
for dry dog foods: [GE=(24 × g protein) + (38 × g fat) + (17 × g NFE), then percentage energy digestibility=91.2 – (1.43 × percentage crude fibre in dry matter), then ME=(GE × percentage energy digestibility) – (4.34 × g protein)].
With the exception of high-fibre weight-management diets, the simple equation [((GE × 1.209)–1.911) × 4.184] also reliably predicted ME in dry dog foods.     

The histamine content of commercial pet foods

The histamine contents of a range of North American commercial pet foods and pet food ingredients were determined by a spectrofluorometric technique. The change in histamine content of open cans of pet food stored in a refrigerator or at room temperature was also investigated. The histamine content of the pet foods examined ranged from a low of 0.16 microg/g in a liquid critical care diet to a high of 65.5 microg/g in a canned fish diet. The amount of histamine in the foods tested was insufficient to cause histamine toxicosis but it cannot be excluded that some of the foods contained sufficient histamine to cause idiosyncratic reactions in histamine-sensitive cats. Storage of opened cans of pet food, either under refrigeration or at room temperature, did not significantly increase the histamine content of most pet foods.     

The histamine content of commercial pet foods

The histamine contents of a range of North American commercial pet foods and pet food ingredients were determined by a spectrofluorometric technique. The change in histamine content of open cans of pet food stored in a refrigerator or at room temperature was also investigated. The histamine content of the pet foods examined ranged from a low of 0.16 𝛍g/g in a liquid critical care diet to a high of 65.5 𝛍g/g in a canned fish diet. The amount of histamine in the foods tested was insufficient to cause histamine toxicosis but it cannot be excluded that some of the foods contained sufficient histamine to cause idiosyncratic reactions in histamine-sensitive cats. Storage of opened cans of pet food, either under refrigeration or at room temperature, did not significantly increase the histamine content of most pet foods.     

Intake of lambs offered ad libitum access to one of three iso-caloric and iso-nitrogenous mixed rations or a choice of all three foods

Modern practices for finishing livestock typically involve offering a single uniform food to large groups of presumably similar animals in an attempt to increase efficiency. Nevertheless, differences in physiology and behavior still cause variations in performance that may precipitate biological inefficiencies by not appreciating the importance of differences among individuals, the capacity of animals to select foods that meet ever-changing individual needs, and the dynamic nature of a nutrient's value to an animal. We examined intakes of groups of lambs offered a single food or three foods differing only in their proportions of cereal grains: High, 70%; Medium, 50%; Low, 40%. Foods consisted of the same ingredients (barley, corn, sugar beet pulp, alfalfa, soybean meal, grape pomace, feather meal, wheat straw), had similar levels of metabolizable energy (ME) and crude protein (CP), and met NRC requirements. We hypothesized that intake and performance would be greater when animals had a choice of foods because high grain concentrations would not limit intake of individuals unable to process high amounts of energy from grain. In general, lambs offered a Choice of the three foods ate more, converted food more efficiently, and cost less per unit gain than lambs fed the High food (P < 0.05). Animals fed the Low or Medium foods were intermediate in their responses between these two extremes. Within Choice, preference for High, Medium, and Low shifted from the beginning (21 d) to the finishing (21 d) periods of the trial. Though lambs in the Choice treatment preferred Low > Medium and High in the beginning stage of the trial, their preferences became pronounced as we increased the amount of grain in each food during the finishing period (P < 0.05). Collectively, our findings suggest improved intake, rate of gain, and feed efficiency can result when animals are allowed to select their diets from biochemically complementary foods, possibly enabling them to realize greater benefits than typically thought from inexpensive forages. In addition, offering animals choices is an alternative to feeding uniform diets of rapidly fermented energy, a major cause of illness in feedlots.     

Dietary patterns of cats with cardiac disease

OBJECTIVE: To determine nutrient intake and dietary patterns in cats with cardiac disease. DESIGN: Prospective study. ANIMALS: 95 cats with congenital cardiac disease or primary cardiomyopathy. PROCEDURES: Owners completed a standardized telephone questionnaire regarding their cat's diet and a 24-hour food recall to determine daily intake of calories, fat, protein, sodium, magnesium, and potassium. RESULTS: Of the 95 cats, 18 (19%) had a history of congestive heart failure and 73 (77%) had no clinical signs of cardiac disease. Fifty-five percent (52/95) of cats had concurrent disease. Inappetance was reported in 38% (36/95) of all cats and in 72% (68/95) of cats with a history of congestive heart failure. Most (57% [54/95]) cats received treats or table scraps on a regular basis. Approximately half the cats were receiving orally administered medications, supplements, or both. Only 34% (32/68) of owners used food to administer medications to cats. Cats consumed more than the Association of American Feed Control Officials (AAFCO) minimums for protein, sodium, potassium, and magnesium, and nearly all cats consumed more than the AAFCO minimum for fat. Daily nutrient intake was variable for all of the nutrients assessed. CONCLUSIONS AND CLINICAL RELEVANCE: Dietary intake in cats with cardiac disease was variable, but results for dietary supplement use, food use for medication administration, and treat feeding were different from those found in a similar study of dogs with cardiac disease. This information may be useful for treating and designing nutritional studies for cats with cardiac disease.     

使用猪T型瘘管法测定饲料原料氨基酸回肠末端表观消化率

使用 8头T型瘘管猪测定了 4种饲料原料的猪回肠末端氨基酸表观消化率。结果说明玉米和豆粕的氨基酸回肠末端表观消化率与最近的文献报道值较为一致 ,羽毛粉的氨基酸表观消化率有一定的趋势 ,乳清粉的氨基酸表观消化率与中国饲料数据库的推荐值较为吻合。这些数据可以为我国的氨基酸消化率数据库提供参考 ,并且可以作为以可消化氨基酸为基础配制日粮时的依据     

A comparison of certified and noncertified pet foods.

The market presents the buyer with a wide array of pet food choices. Marketing pet foods has changed in the last decade and today foods may be bought at a variety of outlets. The present study compares nutrient composition, digestibility, and effect on urine pH (cat foods only) of selected certified and noncertified pet foods from different outlets. The selected foods were considered analogous in terms of declared ingredients and macronutrient profiles. The analytical methods used were those of the Association of Official Analytical Chemists as described in the Pet Food Certification Protocol of the Canadian Veterinary Medical Association. The test foods were sampled 4 times from August 1994 to July 1995. Both certified and noncertified products met the nutritional requirements on a consistent basis, although 1 of the noncertified dog foods consistently failed to meet the zinc requirements. This same product also failed to meet the Canadian Veterinary Medical Association's standards for concentrations of protein, calcium, and phosphorus. One of the noncertified cat foods failed to meet the recommended calcium level. With the exception of fat digestion in 1 noncertified food, there were no statistically significant differences in major nutrient digestibility between certified and noncertified pet foods. There were some statistically significant differences in digestibility within both the certified and noncertified groups of foods. The practical significance of any of the statistical differences in digestibility is uncertain. Urine pH observed in cats fed noncertified test diets was variable, with some values greater than 7.0 as a maximum or 6.5 as an average. The general conclusion of this study was that the commonly available certified products were the nutritional equal of those foods that position themselves as "premium."     

烟酸及胆碱对围产期奶牛营养代谢的调控

围产期是奶牛泌乳周期中十分重要的时期,奶牛要经历生理、日粮、环境和管理等一系列变化,因此,采食量下降,机体处于能量和其他营养素的负平衡状态,易诱发多种代谢性疾病,如脂肪肝和酮病等。烟酸和胆碱能够调控脂肪代谢,提高产后泌乳性能,改善奶牛健康。本文总结了烟酸和胆碱的理化性质、生理功能及其对围产期奶牛营养代谢的调控机理,为进一步研究烟酸、胆碱在奶牛围产期合理应用及保障围产期奶牛健康提供参考。     

Survey of copper and zinc concentrations in commercially available dry ferret diets

BackgroundTo survey macronutrients and two micronutrients (copper and zinc) in commercial ferret diets to investigate dietary factors that may influence copper-associated hepatopathy in ferrets.MethodsProximate analysis and copper and zinc concentrations of 12 commercially available dry adult maintenance ferret diets. Medians were calculated on a dry matter and metabolizable energy basis and compared to the Association of American Feed Control Officials (AAFCO) nutrient profiles for cats and the National Research Council (NRC) recommendations for mink.ResultsCalculated metabolizable energy of diets ranged from 3830 to 4305 kcal/kg dry matter (DM). Crude protein ranged from 89.1 to 151.4 g/1000 kcal, nitrogen-free extract ranged from 13.9 to 124.7 g/1000 kcal, and crude fat ranged from 29.6 to 52.4 g/1000 kcal. The median copper concentration was 9.0 mg/1000 kcal and 37.8mg/kg DM, 7 times the AAFCO minimum for cats and 6.3 times the recommendation for mink. Median zinc concentration was 64.2 mg/1000 kcal and 243.1mg/kg DM, 3.4 times the AAFCO minimum for cats and 3.7 times the NRC recommendation for mink. The median zinc to copper ratio was 6.7.Conclusions and Clinical RelevanceThere is considerable variation in micro- and macronutrient composition among tested commercial ferret diets. High copper concentrations in ferret diets may contribute to copper-associated hepatopathy in ferrets.     

ELISA testing for common food antigens in four dry dog foods used in dietary elimination trials

This study evaluated four over the counter venison dry dog foods available from one on-line retail vendor for potential contamination with common known food allergens: soy, poultry or beef. An amplified, double sandwich type enzyme linked immunosorbent assay (ELISA) test of soy, poultry and beef proteins were performed by an independent accredited food laboratory. The ELISA test for poultry protein was found to be unreliable when testing in dry dog foods because false negatives occurred. ELISA testing of control diets for both soy and beef proteins performed as expected and could be useful in antigen testing in dry dog foods. Three of the four over the counter (OTC) venison canine dry foods with no soy products named in the ingredient list were ELISA positive for soy; additionally one OTC diet tested positive for beef protein with no beef products listed as an ingredient list. One OTC venison diet was not found to be positive for soy, poultry or beef proteins. However, none of the four OTC venison diets could be considered suitable for a diagnostic elimination trial as they all contained common pet food proteins, some of which were readily identifiable on the label and some that were only detected by ELISA. Therefore, if the four OTC venison products selected in this study are representative of OTC products in general, then the use of OTC venison dry dog foods should not be used during elimination trials in suspected food allergy patients.     

Effects of dietary fat and L-carnitine on plasma and whole blood taurine concentrations and cardiac function in healthy dogs fed protein-restricted diets

OBJECTIVE: To evaluate plasma taurine concentrations (PTC), whole blood taurine concentrations (WBTC), and echocardiographic findings in dogs fed 1 of 3 protein-restricted diets that varied in fat and L-carnitine content. ANIMALS: 17 healthy Beagles. DESIGN: Baseline PTC and WBTC were determined, and echocardiography was performed in all dogs consuming a maintenance diet. Dogs were then fed 1 of 3 protein-restricted diets for 48 months: a low-fat (LF) diet, a high-fat and L-carnitine supplemented (HF + C) diet, or a high-fat (HF) diet. All diets contained methionine and cystine concentrations at or above recommended Association of American Feed Control Officials (AAFCO) minimum requirements. Echocardiographic findings, PTC, and WBTC were evaluated every 6 months. RESULTS: The PTC and WBTC were not significantly different among the 3 groups after 12 months. All groups had significant decreases in WBTC from baseline concentrations, and the HF group also had a significant decrease in PTC. One dog with PT and WBT deficiency developed dilated cardiomyopathy (DCM). Taurine supplementation resulted in significant improvement in cardiac function. Another dog with decreased WBTC developed changes compatible with early DCM. CONCLUSIONS AND CLINICAL RELEVANCE: Results revealed that dogs fed protein-restricted diets can develop decreased taurine concentrations; therefore, protein-restricted diets should be supplemented with taurine. Dietary methionine and cystine concentrations at or above AAFCO recommended minimum requirements did not prevent decreased taurine concentrations. The possibility exists that AAFCO recommended minimum requirements are not adequate for dogs consuming protein-restricted diets. Our results also revealed that, similar to cats, dogs can develop DCM secondary to taurine deficiency, and taurine supplementation can result in substantial improvement in cardiac function.     

Effect of starch gelatinisation on nutrient digestibility and plasma metabolites in pigeons

Feed manufacturing exerts physical and chemical changes in ingredients, including the gelatinisation of starch. Studies on the effect of the degree of starch gelatinisation on nutrient digestibility, metabolism and subsequent performance show inconsistent results, and no data are available in pigeons. In a cross‐over trial, fourteen adult pigeons were randomly divided into two groups, in which two extruded pellet diets were tested. Both the diets were similar in ingredient composition and nutrient content, but differed in extrusion conditions, resulting in a different degree of starch gelatinisation: pellets with high gelatinisation degree (HG; 73.6% gelatinisation) and low gelatinisation degree (LG; 53.1% gelatinisation). After a 14‐day adaptation period, all excreta were gathered per bird during a 5‐day collection period. Coefficients of apparent digestibility of dry matter (DM), crude protein (CP), ether extract (EE), crude fibre (CF), crude ash (CA) and nitrogen free extract (NFE) as well as apparent nitrogen retention were calculated from proximate analyses of feed and excreta. Further, excreta consistency was subjectively scored. Blood samples were taken at the end of each period and plasma samples were analysed for glucose, fructosamine and triglycerides. Feed intake and body weight changes were recorded weekly. The apparent digestibility coefficients (ADCs) of DM, OM, CP, EE, CA and NFE were significantly higher in the LG group (p ≤ 0.05). The ADC of crude fibre was numerically higher in the LG group but not significant, and no significant differences were found in starch digestibility. Excreta consistency score tended to be higher in the LG diet group. Neither plasma glucose nor plasma fructosamine values were significantly different between the two test diets. The results of this study show that lower degree of starch gelatinisation in extruded diets can enhance digestibility in pigeons.     

Tyrophagus putrescentiae mites grown in dog food cultures and the effect mould growth has on mite survival and reproduction

The purposes of this study were to determine whether the storage mite, Tyrophagus putrescentiae , could survive and thrive on dog food and if mould growth was important to their survival. All of the chambers ( n  = 42) were started with 10 female mites and evaluated every other day for mite survival and for the spontaneous development of mould. Ten chambers tested the effect of low moisture on mite survival. Eight chambers were used as positive and negative controls ( n  = 4 each); positive control mites were fed Fleischmann's^® yeast and negative controls had no food source. Three dog foods were evaluated in the same manner. Four chambers had food but mould development was limited by replacing the food kernel every 48 h and four chambers were allowed to grow mould. Mites grown in chambers without moisture died from desiccation within 5 days. The termination point was day 34 when all mites in the negative control group (moisture but no food) died. Although T. putrescentiae survived and grew on all three commercial dog foods, there was no statistically significant difference in mites counts among the dog foods ( P  < 0.10). Mite counts in the 'no' mould and mould groups ranged from 8 to 11 and 144 to 245, respectively, and differences were significant ( P  < 0.0001). This study found that T. putrescentiae is a fungivorous storage mite that can grow and flourish on dog food. The study demonstrated that the presence of mould positively influences mite viability, while low relative humidity can result in detrimental consequences for T. putrescentiae.     

Comparison of the cognitive palatability assessment protocol and the two-pan test for use in assessing palatability of two similar foods in dogs

OBJECTIVE: To compare preferences of dogs for 2 similar foods by use of 2 distinct methods (the cognitive palatability assessment protocol [CPAP] and the 2-pan test). ANIMALS: 13 Beagles. PROCEDURE: 6 dogs were trained in a 3-choice object-discrimination-learning task in which their nonpreferred objects were associated with a reward of a lamb-based or chicken-based food. The number of choices for each object was used to determine food preferences. Preference of the same foods was also assessed by use of a 2-pan test in which all 13 dogs were provided the 2 foods in identical bowls. The amount of each food consumed in 10 minutes was used to determine food preference. RESULTS: All dogs had a noticeable preference for the chicken-based food during the CPAP. Once established, preferences remained consistent and were not affected by satiety. The 2-pan test identified a preference for the chicken-based food in dogs with previous exposure to the food but only a weak and nonsignificant preference for the same food in dogs without previous exposure. Food preferences in the 2-pan test varied considerably. Total food consumption and the ability to detect a preference were reduced when dogs were fed prior to testing. CONCLUSIONS AND CLINICAL RELEVANCE: The CPAP provides a reliable measure of food preference that requires few test subjects. The 2-pan test reveals similar preferences but with variability in data that requires larger numbers of subjects and is susceptible to effects from prior exposure and feeding of the test foods to the subjects.