Prediction of chemical composition and peroxide value in unground pet foods by near‐infrared spectroscopy

The massive development of the pet food industry in recent years has lead to the formulation of hundreds of canine and feline complete extruded foods with the objective of meeting both the needs of the animals and numerous demands from pet owners. In the meantime, highly variable raw material compositions and the industry's new production techniques oblige manufacturers to monitor all phases of the extrusion process closely in order to ensure the targeted composition and quality of the products. This study aimed at evaluating the potential of infrared technology (visible and near‐infrared spectrophotometer; 570–1842 nm) in predicting the chemical composition and peroxide value (PV) of unground commercial extruded dog foods. Six hundred and forty‐nine commercial extruded dog foods were collected. For each product, an unground aliquot was analysed by infrared instrument while a second aliquot was sent to a laboratory for proximate analysis and PV quantification. The wide range of extruded dog food typologies included in the study was responsible for the wide variability observed within each nutritional trait, especially crude fibre and ash. The mean value of the 208 pet foods sampled for PV quantification was 17.49 mEq O₂/kg fat (min 2.2 and max 94.10 mEq O₂/kg fat). The coefficients of determination in cross‐validation of NIRS prediction models were 0.77, 0.97, 0.83, 0.86, 0.78 and 0.94 for moisture, crude protein, crude fat, crude fibre, ash and nitrogen‐free extract (NFE) respectively. PV prediction was less precise, as demonstrated by the coefficient of determination in cross‐validation (0.66). The results demonstrated the potential of NIRS in predicting chemical composition in unground samples, with lower accuracy for moisture and ash, while PV prediction models suggest use for screening purposes only.     

Analysis of the nutrient composition of selected commercial pet rabbit feeds with respect to nutritional guidelines

The aim of this study was to evaluate the chemical composition of pet rabbit feeds available on the market with respect to nutritional guidelines and to determine whether the manufacturer's guaranteed analysis differed from the measured analysis. Samples of 5 different rabbit feeds were collected from sealed bags, three per each type of feed. The samples were then ground into a powder using a laboratory mill. Guidelines from the Association of Official Analytical Chemists (AOAC) were used to assess the basic chemical composition of the samples. Four out of 5 feeds did not meet the minimum recommended level for crude fiber and analysis results for this nutrient were up to 67% lower than what was declared on the label. One feed did not meet the established minimum recommended level for crude proteins. In any of the feeds tested the nutrient levels matched the manufacturers guaranteed analysis. In four feeds, the deviations were outside the range of tolerance permitted by law. Results indicate that in the analyzed feeds there is considerable non-compliance with current EU guidelines for pet rabbit food and divergence from the manufacturers’ guaranteed analyses.     

Comparative evaluation of net digestive and absorptive efficiency in dogs and cats fed a variety of contrasting diet types

Comparative net digestive and absorptive efficiency was assessed with adult Beagles and domestic cats by apparent digestibility assays. Eight foods were used comprising two canned dog foods; canned cat foods; two samples of semipurified diet; and single samples of experimental dry cat food and fresh mince. Apparent digestibility percentages of crude protein, fat, nitrogen-free extract (NFE) and gross energy were all significantly higher in dogs than cats. Mean values obtained for dogs were (per cent): crude protein 87; fat 92; NFE 70 and energy 89. Respective values for cats were 82, 76, 67 and 79. On average, dogs obtained 11 and 9 per cent more digestible energy and protein per unit food eaten than cats. Most digestibility characteristics of foods measured in cats were significantly correlated with those for dogs and regression equations are presented predicting digestibility in cats from dog data.     

Changes in the milk composition of okapi (Okapia johnstoni) during the first 6 months of lactation

We collected 17 milk samples at 1 day to 6 months post partum from one captive okapi (Okapia johnstoni). Milks were examined for nutrient composition, including water, fat, crude protein, carbohydrates, ash and five minerals. The average values of the concentrations were 79.2 ± 3.0% SD water, 8.5 ± 3.4% fat, 7.5 ± 1.1% crude protein, 3.6 ± 0.6% carbohydrate, 1.2 ± 0.1% ash, 263.7 ± 47.3 mg/100 g calcium, 183.0 ± 40.0 mg/100 g phosphorus, 95.2 ± 17.6 mg/100 g sodium, 74.4 ± 34.3 mg/100 g potassium and 28.4 ± 4.4 mg/100 g magnesium, respectively. The protein concentration increased at late lactation (P < 0.01). The contents of sodium and potassium were rather high in the early lactation period, while those of calcium and phosphorus were rather low in the early lactation period. During the course of lactation in the first week post partum and the protein concentration was high at 1 day post partum. We compare our findings with the American Association of Zoos & Aquariums's Okapi Species Survival Plan Hand‐rearing Protocol, and recommend that nutrient composition of the formula for okapi calves is developed using the present study as a guide.     

Determination of bisphenol A in canned pet foods

Bisphenol A (BPA) contamination of canned foods for human use has been studied, but there are no reports concerning BPA contamination of canned pet foods. The purpose of this study was to identify the levels of BPA in canned pet foods. A total of 26 samples (15 samples of cat food and 11 samples of dog food) were prepared for analysis by high-performance liquid chromatography. BPA in the samples was extracted with acetonitrile and fat in the sample extract was removed with hexane. Solid-phase extraction was used for sample clean-up prior to final analysis. The concentration of BPA ranged from 13 to 136 ng/g in canned cat food and from 11 to 206 ng/g in dog food. Also, to confirm that the BPA had originated from the can coating, distilled water was added to each washed empty can and the cans were autoclaved at 121 degrees C for 30 min. The concentration of BPA leached from empty cans was between 7 and 31 ng/ml.     

Basic data on food intake, nutrient digestibility and energy requirements of lorikeets

Although knowledge of the nutrient requirements of pet birds has increased a lot over the last few years, basic data on food and water intake and the energy requirements of nectarivorous species, such as lorikeets, are scarce. Thus, the aim of this study was to try to generate some of these data for lorikeets kept at maintenance. Determination of the daily maintenance energy requirement enables calculation of the daily ration and thus, the appropriate nutrient concentrations in order to maintain body weight. Investigations were carried out with six Goldie's lorikeets (GL; Trichoglossus goldiei: 40-50 g BW; 1-4 years) and six rainbow lorikeets (RL; Trichoglossus haematodus haematodus: 120-140 g BW; 1-12 years). Three of the most commonly used diets/foods (commercial 'lory soup'/apples/pollen: crude ash - 52.9/17.8/18.8; crude protein - 178/32.5/191; crude fat - 52.8/0.89/73.1; crude fibre - 17.9/40.5/30.4; starch - 139/not detectable/127; sugar - 522/859/418 g/kg DM; ME - 13.9/14.6/10.9 MJ/kg DM) were individually offered ad libitum. The measured dry matter (DM) intake (g/100 g BW) corresponded well to the values reported for granivorous bird species of similar body mass. Both lorikeet species achieved an apparent digestibility of organic matter of more than 90% for apples, approximately 82% for 'lory soup' and approximately 55% for pollen. The water content of the food affected the DM content of the excreta; 8% when fed 'lory soup', 2% for apples and approximately 30% when fed pollen. Regression analysis of body weight change relative to energy intake demonstrated constant body mass (assuming no change in body composition) when the daily energy intakes were 860 (GL) or 650 (RL) kJ ME/kg BW(0.75).     

Vitamin A concentrations in commercial foods for dogs and cats

The vitamin A concentration was determined in 89 Australian brands of commercial foods for dogs and cats. It was found that 8% of the dog foods and 14% of the cat foods had concentrations of vitamin A below the minimum recommended 1.1 mg/kg dry matter (dm) for dogs and 1.8 mg/kg dm for pregnant or lactating cats. Canned and fish-labelled cat foods were the only varieties with less than the minimum recommended concentration of Vitamin A, of which 71% were the same brand. The minimum recommended concentration of vitamin A was exceeded in all canned dog food tested. Concentrations of vitamin A in dry (ca. 6% moisture) dog and cat foods and semi-moist dog foods (ca. 23% moisture) never exceeded 10 mg vitamin A/kg dm. In contrast, canned pet foods stated to contain liver or kidney showed vitamin A concentrations from 13 to 284 mg/kg dm.     

茶多酚鸡蛋营养成分分析

实验旨在测定茶多酚鸡蛋中的粗蛋白、水分、灰分、脂肪、胆固醇等营养成分的含量,为养殖企业改进饲养管理提供理论依据。粗蛋白的测定用凯氏定氮法,水分、灰分的测定用恒重法,脂肪用索氏提取法测定,胆固醇的含量应用HPLC(高压液相色谱)法测定[色谱条件:Eclipse XPB C18柱(250 mm×4.5 mm);流动相:乙腈-异丙醇(4/1,V/V);检测波长:208 nm;流速1 ml/min;柱温:室温]。实验结果表明,茶多酚鸡蛋中蛋白质、脂肪明显高于普通鸡蛋,水分、灰分、胆固醇则无显著性差异。说明茶多酚鸡蛋是一种高蛋白和富含脂类的蛋品。     

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.     

强旱生植物霸王和红砂地上部营养物质含量及其季节动态

探讨了阿拉善干旱荒漠区强旱生植物霸王Zygophyllum xanthoxylum、红砂Reaumuria Soongorica地上部分可食嫩枝的有机养分如蛋白质、脂肪、纤维素、无氮浸出物和无机养分钙、磷、粗灰分含量的季节动态,以及各营养物质间的相关性.研究结果表明,生长前期纤维素含量较低,其余各养分含量均呈增加趋势,进入生长末期,各养分含量呈下降趋势,纤维素含量则达到最高值.在整个生育期,粗蛋白与粗纤维、粗纤维与粗灰分之间呈显著的负相关关系,粗蛋白与粗灰分、粗蛋白与磷、钙与粗灰分之间均呈显著的正相关关系.     

贵州南部苇状羊茅混播草地营养成份含量动态测定

对在贵州南部地区生态条件下表现优良的草种组合 :苇状羊茅 +扁穗雀麦 +白三叶人工草地各种牧草的各个生育阶段及草地全年各月份营养成份含量进行了测定。结果表明 :四种混播牧草的粗蛋白、粗脂肪和灰分三种营养成份含量都是随着生育期的推后呈线性下降 (P <0 0 1) ,酸性洗涤纤维含量随着生育期的推后呈线性上升 (P <0 0 1) ,无氮浸出物的含量变化跟生育期无明显联系 ;混播草地全年各月份营养成份含量变化规律为 :粗蛋白、粗脂肪及灰分在 1～ 7月份较高 ,8、9、10月份最低 ,11、12月份又逐步回升 ,粗蛋白含量尤以 4、5、6月份含量最高。酸性洗涤纤维的含量变化跟粗蛋白等情况相反 ,无氮浸出物含量各月间无显著变化。     

Prediction of nutrient digestibility in grower-finisher pigs based on faecal microbiota composition

Microbiota play an important role in total tract nutrient digestion, especially when fibrous diets are fed to pigs. This study aimed to use metagenomics to predict faecal nutrient digestibility in grower-finisher pigs. The study design consisted of 160 three-way crossbreed grower-finisher pigs (80 female and 80 male) which were either fed a diet based on corn/soybean meal or a more fibrous diet based on wheat/barley/by-products. On the day before slaughter, faecal samples were collected and used to determine faecal digestibility of dry matter, ash, organic matter, crude protein, crude fat, crude fibre and non-starch polysaccharides. The faecal samples were also sequenced for the 16S hypervariable region of bacteria (V3/V4) to profile the faecal microbiome. With these data, we calculated the between-animal variation in faecal nutrient digestibility associated with variation in the faecal microbiome, that is the “microbiability”. The microbiability values were significantly greater than zero for dry matter, organic matter, crude protein, crude fibre and non-starch polysaccharides, ranging from 0.58 to 0.93, as well as for crude fat with a value of 0.37, but not significantly different from zero for ash. Using leave-one-out cross-validation, we estimated the accuracy of predicting digestibility values of individual pigs based on their faecal microbiota composition. The accuracies of prediction for crude fat and ash digestibility were virtually 0, and for the other nutrients, the accuracies ranged from 0.42 to 0.63. In conclusion, the faecal microbiota composition gave high microbiability values for faecal digestibility of dry matter, organic matter, crude protein, crude fibre and non-starch polysaccharides. The accuracies of prediction are relatively low if the interest is in precisely predicting faecal nutrient digestibility of individual pigs, but are promising from the perspective of ranking animals in a genetic selection context.     

Estimated nutrient content of diets commonly fed to pet birds

The owners of 135 pet birds were surveyed by questionnaire to determine their birds' weekly food consumption. The birds were divided into six food groups on the basis of the amounts of seeds, formulated products and human food they consumed. The formulated products and seeds were analysed for their nutrient content by two independent laboratories, the nutrient content of the human foods was obtained from a standard nutrition reference, and each bird's nutrient intake was estimated. The dietary content of individual nutrients was then compared with the estimated maintenance requirements for pet birds. Birds consuming less than approximately 50 per cent of their diets as formulated products had inadequate intakes of vitamins A and D3, and calcium. Diets high in human food were low in protein, energy, vitamins and minerals. Diets high in seed were excessive in fat and deficient in vitamins A and D3, and calcium.     

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.     

Nutrient Composition Comparison of Longissimus Dorsi between Diannan Small-ear Pigs and DLY Commercial Pigs

This study was conducted to compare the nutrient composition of longissimus dorsi between Diannan Small-ear pigs and DLY commercial pigs.53 Diannan Small-ear pigs and 58 DLY commercial pigs were chosen and longissimus dorsi samples were collected to determine the content of moisture,crude protein,crude fat,ash,amino acids and fatty acids.The results showed that the moisture content of Diannan Small-ear pigs was extremely significantly lower than DLY commercial pigs (P < 0.01).However,the content of crude protein and crude fat were extremely significantly higher than DLY commercial pigs (P < 0.01).And there was no significant difference in ash content (P > 0.05).The levels of threonine,valine,methionine,isoleucine,leucine,lysine and phenylalanine in longissimus dorsi of Diannan Small-ear pigs were extremely significantly higher than that of DLY commercial pigs (P < 0.01),and the content of myristic acid,palmitic acid,oleic acid,cis different oleic acid,11-cis-20 carbon olefine acid,saturated fatty acids,monounsaturated fatty acids and the total fatty acids in longissimus dorsi of Diannan Small-ear pigs were also extremely significantly higher than that of DLY commercial pigs (P < 0.01).In conclusion,Diannan Small-ear pigs had a better value in nutrient and development.     

The relationship of feeding patterns and obesity in dogs

The rates of dog obesity are increasing and a greater understanding of feeding patterns is required to combat the problem. This study examined relationships between dietary patterns and caloric intake, and nutrient content of foods fed as it relates to obesity in dogs in the United States. Sixty‐one owners and their dogs were enrolled, and lifestyle surveys, food frequencies, and 3‐day food records were collected. Significant differences in overall kcal intake per kilogram of body weight were found (p < 0.04). Crude fibre in dog food was positively associated with protein and negatively associated with fat regardless of the dog’s weight (p < 0.001). Lean dogs received significantly more crude fibre in relation to overweight dogs regardless of the number of treats they received (p < 0.01), and their diets had greater micronutrient densities (p < 0.03) suggesting that high fibre influences body condition. Additionally, owners who ate nutrient‐rich, calorie‐poor diets had normal weight dogs, and owners that fed more table scraps had overweight dogs. Regardless of body condition, 59% of dogs received table scraps, which constituted 21% of daily caloric intake. The nutrient density of scraps fed was variable and did not meet National Research Council’s recommendations for micronutrient adequacy.     

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.     

滇南小耳猪与DLY商品猪背最长肌营养成分比较分析

本试验为比较研究滇南小耳猪与DLY商品猪肉的营养价值,分别检测了53头滇南小耳猪和58头DLY猪背最长肌肉的水分、粗蛋白质、粗脂肪、灰分、氨基酸及脂肪酸等营养成分含量,比较分析其差异性。结果显示,滇南小耳猪背最长肌的水分含量极显著低于DLY商品猪背最长肌（P < 0.01）,粗蛋白质、粗脂肪含量极显著高于DLY商品猪（P < 0.01）,灰分含量差异不显著（P > 0.05）;其中滇南小耳猪背最长肌的7种必需氨基酸（苏氨酸、缬氨酸、蛋氨酸、异亮氨酸、亮氨酸、赖氨酸、苯丙氨酸）、肉豆蔻酸、棕榈酸、油酸、顺式异油酸、11-顺-二十碳烯酸,饱和脂肪酸、单不饱和脂肪酸、总脂肪酸含量均极显著高于DLY商品猪（P < 0.01）。综上所述,滇南小耳猪与DLY猪相比具有更高的营养价值和开发价值。     

Predictive equations of selenium accessibility of dry pet foods

The trace element selenium is essential to both dogs and cats. Dry diets are formulated with a large range of ingredients, which may vary in selenium concentration and accessibility. This paper reports equations to predict the average in vitro selenium accessibility from dry pet foods based on essential dietary nutrient concentrations, including crude protein, amino acids and crude fat. Predictive equations were made using stepwise linear regression for extruded and pelleted diets. The equations can be used to aid diet formulation to optimize selenium accessibility within the diet and to prevent selenium deficiency or toxicity.     

The deer industry: a veterinary perspective

Fitch diets from 30 farms were surveyed and analysed for moisture, protein, carbohydrate, fibre, ash, fat and individual fatty acids, fat peroxide value, and ∝-tocopherol. The dietary raw materials most often used were mutton, fish, poultry, beef and cereals. Eight of the 30 breeders added no vitamin or other supplements. Analytical mean (range) values on a wet matter basis were: moisture, 66.3 (49.6–76.8)%; protein, 16.5 (12.4–21.2)%; carbohydrate, 2.5 (<0.1-8.7)%; fibre, 0.4 (0.1–1.0)%; ash, 3.7 (1.2–8.3)%; fat, 10.6 (1.4–26.1)%; peroxide value, 5.7 (0.3–110) m.equiv./kg fat; ∝-tocopherol, 13 (0.6–103) mg/kg; calculated gross energy value, 7.2 (3.7–13.7) MJ/kg. Protein contributed 42 (20–79)% of the gross energy value; fat, 49 (15–74)%, and carbohydrate, 6 (0–20)%. Polyunsaturated fatty acids (PUFA's) comprised 10 (3.6–39)% of the total fatty acids. The ratio of ∝-tocopherol to PUFA was 2.1 (0.1–10.5) mg/g. Results of the survey are discussed in the light of nutrient requirements for the fitch.