Nutritional support of hospitalized patients

Effective nutritional support requires sound knowledge of both basic and clinical nutrition of dogs and cats as well as familiarity with products and delivery systems. Case management includes assessment of nutritional status and estimation of fuel sources. Most starved or stressed patients use fatty acids for over 70 per cent kcalME and protein for over 20 per cent kcalME. Approximate kcal needs are calculated from maintenance energy equations. Most patients respond best to enteral nutrition. Meat-based pet foods, liquid enteral products, and nutrient modules are offered in slurries or are tube-fed. Management includes careful monitoring of patients and gradual transitions to diets with more complex nutrient sources.     

Synthetic oestrogens in the production of roasting fowl. II. Dietary nutrient concentration and time of implantation

Three experiments have been carried out using broiler‐type birds reared beyond the normal broiler stage to 14 weeks of age. In the first experiment control cockerels were compared with birds injected with either a 15 mg. hexoestrol pellet or a 15 mg. pellet of diethylstilboestrol at 9 weeks of age: at this stage three diets of different nutrient density were offered. As the nutrient density was increased, food utilisation progressively improved and growth rates were raised. Hexoestrol implantation resulted in an increase in voluntary food intake of 23 per cent above the control whereas diethylstilboestrol implantation increased voluntary food intake by only 14 per cent. These increases in food intake were associated with proportional increases in live‐weight gain.

In a second experiment pullets received 15 mg. implants of hexoestrol at 64 days of age, and were then fed diets of different nutrient concentrations to 98 days of age. Live‐weight gain tended to improve as nutrient density was raised, and efficiency of food utilisation was inversely proportional to nutrient density.

In a third experiment male birds were reared from 70 to 119 days of age. Four different implantations with hexoestrol at various ages were compared: only in those receiving two implants was there any difference in performance. Six diets varying in energy level and protein level were offered. Growth rates improved as dietary protein levels were raised progressively from 13.3 to 16.3 per cent, though food utilisation was most efficient at 14.8 and 16.3 per cent crude protein. Growth rate was 7.6 per cent greater when the dietary energy level was raised from 3065 to 3275 kcal. metabolisable energy per kg.     

The protein requirements of two strains of laying pullets

Diets with 16.5, 14.5, 12.5 and 10.5 per cent protein and 2765 k cal. metabolisable energy per kg. and a fifth diet containing 10.5 per cent protein and 2165 k cal. M.E./kg. were fed to Rhode Island Red x Light Sussex pullets and to “hybrid” pullets which weighed 33 per cent less and produced 20 per cent more eggs. Both strains had protein requirements of the order of 20 g./bird/day. It is possible that the assumed higher requirement of the “hybrid” pullets for productive purposes was offset by a smaller requirement for maintenance and growth. Expressed as a percentage of a 2765 k cal. diet, the small strain required at least 16.5 per cent protein and the large strain no more than 12.5 per cent protein for maximum performance. Both strains performed well on the 2165 k cal., 10.5 per cent protein diet, illustrating that high energy diets are not essential for small strains of pullets.

Egg size was reduced by protein restriction in the heavy strain but not in the light strain. On isocaloric diets the light strain consumed more food only at the lowest protein level whereas the heavy strain tended to eat progressively more as the protein was reduced from 16.5 to 12.5 per cent. When offered the low energy diet both strains ate more food, but substantially fewer calories, than when given diets of 2765 k cal. M.E./kg. Protein restriction had a marked effect in reducing live‐weight gains. Energy level of the diet had a large effect on weight gain and also on fat deposition in the carcass.

The greatest differences in performance due to diet did not occur at the time of maximum egg output. The evidence indicates that a diet which is too low in protein to support peak egg production will also fail to support normal egg production at any later stage of the laying year.     

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.     

Protein Characteristics of Commercial Canine and Feline Hypoallergenic Diets

Résumé— Huit aliments humides pour chat, treize aliments humides pour chien et neufs aliments seés pour chien utilisés comme régimes d'élimination, recommandés ou vendus comme aliment hypoalergénique ont été comparés sur la base: des sources protéiques, de la quantité et de la digestibilité des protéines. Le nombre de sources de protéines variait de deux à neuf. La quantité de protéines (basée sur la matière sèche) variait de 8 à 40 pour cent dans les produits pour chiens et de 27 à 41 pour cent dand les produits pour chats. En se basant sur des différences statistiquement significatives les aliments pour chats et les boites pour chiens ont été classés en trois catégories de digestibilité, les aliments seés pour chiens en deux catégories. II a été proposé que seuls les produits contenant des protéines de haute ou très haute digestibilité soient utilisés chez les animaux suspects d'intolérances alimentaires. [Protein characteristics of commercial canine and feline hypoallergenic diets. (Charactéristiques des protéines des aliments hypoallergéniques industriels pour le chien et le chat.) Abstract— Eight feline, 13 canned canine and nine dry canine commercial pet foods used as elimination diets, recommended or marketed as hypoallergenic diets were compared for protein sources, protein quantity and protein digestibility. The number of protein-containing ingredients varied from two to nine. Protein quantity (dry matter basis) varied from 8 to 40 per cent in canine products and 27–41 per cent in feline products. Based on statistically significant differences, feline diets were classified into three categories of protein digestibility, canned canine diets into three categories, and dry canine diets into two categories. It is suggested that only those products with high or very high protein digestibility should be routinely recommended for patients with suspected adverse reactions to food.     

Dietary management of chronic renal disease in dogs: A critical appraisal

Diets low in protein have been recommended for dogs with chronic renal failure (CRF) since 1948, and for apparently healthy old dogs since 1960. These recommendations were based on studies of rats and poorly documented clinical experiences with dogs. Since 1979, a series of eight experiments on partially nephrectomised dogs and four clinical trials on naturally occurring chronic renal disease have demonstrated serious disadvantages of diets that contained high (38 to 49 per cent on a metabolisable energy (ME) basis) or very low (3 to 10 per cent) protein. In addition to poor acceptance of low protein (12 and 16 per cent) diets, undesired responses included exacerbation of depressed renal functions, reduced renal reserve, severe hyperfiltration in single nephrons, metabolic acidosis, hypercholesterolaemia, and hypertension. Protein deficiency may not have caused the complications observed, and may have been due to another feature of the diets fed. In seven studies, diets with a moderate (20 to 31 per cent ME) protein level fared better in regard to reduced renal pathology and proteinuria, better renal functions and reserve, and improvement of clinical status, azotaemia, hyperphosphataemia and anaemia. In the first instance, preferred products for CRF should contain moderate (20 to 24 per cent) protein and minimal phosphorus. Taking into consideration these 12 kidney studies a protein content of 30 per cent is recommended for apparently healthy old dogs. Current recommendations are to introduce a diet that is low in protein at a ‘critical point’ in the course of CRF, when its advantages are likely to outweigh its possible disadvantages. When this critical point has been reached has not been determined, but it is likely to be based on an assessment of the individual case.     

Effects of segregation and impact of specific feeding behaviour and additional fruit on voluntary nutrient and energy intake in yellow‐shouldered amazons (Amazona barbadensis) when fed a multi‐component seed diet ad libitum

Parrots are commonly fed multi‐component seed diets; however, both segregation and feeding behaviour might alter ingredient and nutrient composition of the offered diet. First, the nutritional impact of segregation was assessed as it occurs when multi‐component diets are temporarily stored in food containers that are replenished before completely emptied and birds being fed from the upper layer. The most detrimental effect hereof was a vast decrease in mineral supplements, leading to a decrease in Ca:P ratio in the offered food in relation to the formulated diet. Next, caloric distribution shifted towards more EE energy at the expense of NFE energy, as proportion of oilseeds increased and NFE‐rich seeds decreased. Next, a feeding trial was performed on six yellow‐shouldered amazons (Amazona Barbadensis) in which nutritional impact of parrot‐specific feeding behaviour was assessed as well as the influence of additional provision of fruit next to the seed mixture. Profound selective feeding behaviour and dehusking of seeds resulted in a vast increase in energetic density by up to 64% in the ingested fraction in relation to the offered mixture in toto. Furthermore, the already suboptimal Ca:P ratio further deteriorated and caloric distribution shifted by over twofold towards EE energy accompanied with a vast decline in NFE energy, CP energy remaining similar. Finally, provision of fruit next to the seed diet significantly lowered voluntary energy intake from 936 ± 71 to 809 ± 109 kJ ME/kg^0.75/day, without compromising adequate protein intake. In conclusion, notwithstanding efforts of nutritionists to formulate diets to approximate estimated, species‐specific requirements, nutritional composition of the actually consumed fraction of multi‐component seed diets can be vastly deteriorated by both animal and management factors. Furthermore, offering of fruit next to a seed‐based diet effectively reduces voluntary energy intake and can hence be applied to abate obesity.     

Ileal and total tract nutrient digestibilities and fecal characteristics of dogs as affected by soybean protein inclusion in dry, extruded diets

Plant-based protein sources are generally less variable in chemical composition than animal-based protein sources. However, relatively few data are available on the nutrient digestibilities of plant-based protein sources by companion animals. The effects of including selected soybean protein sources in dog diets on nutrient digestion at the ileum and in the total tract, as well as on fecal characteristics, were evaluated. Six protein sources were used: soybean meal (SBM), Soyafluff 200W (soy flour), Profine F (traditional aqueous-alcohol extracted soy protein concentrate [SPC 1]), Profine E (extruded SPC [SPC 2]), Soyarich I (modified molecular weight SPC [SPC 3]), and poultry meal (PM). All diets were extruded and kibbled. Test ingredients varied in CP and fat contents; however, diets were formulated to be isonitrogenous and isocaloric. Nutrient intakes were similar, except for total dietary fiber (TDF), which was lower (P < 0.01) for dogs fed the PM diet. Apparent ileal digestibilities of DM, OM, fat, and TDF were not different among treatments; however, CP digestibility at the terminal ileum was higher (P < 0.01) for diets containing soy protein sources than for PM. Total tract CP digestibility was greater (P < 0.01) for soy protein-containing diets than for PM. Apparent total tract digestibilities of DM, OM, fat, and TDF were not different among treatments. Apparent amino acid digestibilities at the terminal ileum, excluding methionine, threonine, alanine, and glycine, were higher (P < 0.01) for soy protein-containing diets than for PM. Dogs fed SPC diets had lower (P < 0.01) fecal outputs (g asis feces/g DMI) than dogs fed the SF diet, and dogs fed SBM tended (P < 0.11) to have lower fecal outputs than dogs fed the SF diet. However, dogs fed the PM diet had lower (P < 0.03) fecal outputs than dogs fed SPC-containing diets. Fecal outputs and scores reflected the TDF and nonstructural carbohydrate contents of the soy protein fraction. Soy protein sources are well utilized by the dog prior to the terminal ileum, and SPC offers a viable alternative to PM as a protein source in dry, extruded canine diets.     

Comparison of laying rations with and without animal protein at the Canadian Random Sample Egg Production Test

For a number of years, the laying ration fed to the hens at the Canadian Random Sample Egg Production Test has contained foodstuffs of animal origin to the extent of 3 per cent meat meal, 2 per cent fish meal, 1 per cent dried whey and 2 per cent tallow. Recently, over a period of 2 years, this ration was compared with a modification in which all of the animal products except tallow were removed. The proportions of the remaining ingredients in the modified diet were adjusted to keep protein, energy, calcium and phosphorus levels comparable in the two rations.

In the first test year, the modified diet was slightly superior to the control diet in terms of egg numbers, egg weight and egg quality. In the second year, there were no significant differences in these traits between diets. Although 17 strains were tested in the first year, and 14 in the second, no significant strain × ration interactions occurred in any performance trait.

These trials provided no evidence that the laying hen responds to unknown factors contained in animal products. There was also no evidence that the removal of animal products adversely affected protein quality, although dietary protein levels may not have been low enough to reveal such a change.     

Nutritional plan: matching diet to disease

Institution of appropriate, timely nutritional support in the anorexic or critically ill patient has become accepted medical practice in people and animals. This article focuses on the benefits of appropriate nutrient intake in critically ill animals, recommended nutrient requirements for dogs and cats receiving enteral feeding, and mechanics of food preparation and delivery for a variety of feeding tubes. General nutrient requirements for all patients, specific recommendations for certain illnesses such as renal failure, pancreatitis, and hepatic disease, and nutritional alterations for critical illness are reviewed. Commercial liquid diets manufactured for people and pets, and pet-food diets practical for formulation of gruel are presented. Institution of and weaning from feeding are explained.     

Supplementation of diets containing pea meal with exogenous enzymes: effects on weight gain,feed conversion,nutrient digestibility and gross morphology of the gastrointestinal tract of growing broiler chicks

1. The potential for the nutritional improvement of pea-based diets by supplementation with a cocktail of exogenous carbohydrases was investigated using growing broiler chicks. 2. Pea meals (grown in the UK) were included in wheat-based diets at 300 g/kg as a partial replacement for an approximately isonitrogenous mixture of wheat and soybean meal. A wheat/soybean meal diet served as a control and each diet was supplemented with a cocktail of alpha-amylase, pectinase and cellulase. The diets were fed to 1-d-old broiler chicks for a period of 21 d. Weight gain and feed conversion were monitored weekly and excreta were collected during the final week in order to determine nutrient digestibility coefficients and metabolisable energy. On d 21, the gastrointestinal (GI) tract was excised and gross morphology measured. 3. Inclusion of pea meal reduced weight gain, feed conversion, nutrient digestibility and also increased the relative sizes of the distal sections of the GI tract. 4. Enzyme addition partially ameliorated the detrimental effects of pea meal inclusion although similar improvements were also noted for birds fed on the control diet. 5. It is concluded that the nutritive value of pea-meal-based diets can be improved by the addition of carbohydrases, and that some pea cultivars show considerable potential as vegetable protein sources for broiler chicks.     

不同净能水平的低蛋白日粮对猪生长性能和养分消化率的影响

选取120头22kg左右的杜×长×大三元杂交健康生长猪,随机分成5个处理,每个处理6个重复,每个重复4头,探讨低蛋白不同净能水平(10.54、10.28、9.96、9.63、9.45MJ/kg)日粮对生长猪生长性能和养分消化率的影响。结果表明:日粮蛋白降低4个百分点,不同净能处理间的采食量和饲料转化率没有显著差异(P>0.05),日增重随净能的下降呈线性增加,以9.45MJ/kg组最高(P<0.05);养分消化率中,除钙的消化率外,其余养分的消化率均随净能水平的增加而线性下降(P<0.05)。降低净能水平后,血清赖氨酸含量线性增加(P=0.03),对其余氨基酸影响差异不显著(P>0.05);对血清尿素氮含量的影响不显著(P>0.05)。由此可得出,低蛋白日粮中净能水平的降低并不影响生长猪的生长性能和养分消化率。     

The effect of dietary nutrient concentration and calorie to protein ratio on growth and body composition of male and female turkey poults

Sixteen all‐mash starter diets, with calculated energy levels of 2205, 2646, 3086 and 3527 kcal ME/kg and calorie to protein ratios of about 93, 104, 115 and 126, were fed ad libitum to male and female poults from o to 4 weeks of age. The effect of dietary treatment on growth and body composition was similar for males and females. Growth rate increased by as much as 30 per cent as dietary energy level was increased from 2205 to 3086 kcal ME/kg. This effect was due to changes in nutrient intake associated with almost no change in food intake. A small additional growth response was obtained when energy level was raised from 3086 to 3527 kcal ME/kg but this was mainly associated with an increase in body fat.

Increasing the nutrient concentration and widening the calorie to protein ratio both caused an increase in the percentage of fat and a decrease in the percentage of protein in the body. Nitrogen retention improved as dietary energy level was increased but not beyond 3086 kcal ME/kg.     

Nutrient–drug interactions in nutritional support

Abstract Objective: To review the types and potential consequences of diet/nutrient–drug interactions that can occur in patients receiving nutritional support. Data sources: A literature review was performed using Ovid multi‐database searching including Medline, Agricola and Biosis. Summary: Although very little information is currently available that pertains specifically to veterinary patients, we know from the human experience that food intake and diet composition can affect the absorption, distribution, metabolism, efficacy and toxicity of a drug. Conversely, certain drugs can alter the absorption of nutrients when administered in conjunction with food or act to antagonize nutrient metabolism or function. The different ways that incompatibility can arise between food or nutrients and drugs in patients receiving nutritional support and strategies for avoiding these problems are discussed. Conclusions: The consequences of diet/nutrient–drug interactions include decreased tolerance of nutritional support, loss of feeding access, decreased drug efficacy, nutrient malabsorption or malassimilation, and risk of drug overdosage. Therefore, when patients receiving nutritional support experience these types of complications, a review of the diet, route of nutritional support, drugs, and timing of feeding and medication administration are indicated.     

A chick growth test for the evaluation of protein quality in cereal-based diets. I. Development of the method

A chick growth test of the protein efficiency ratio (PER) type has been developed in which chicks previously fed a normal starting diet containing 21 per cent protein are given, from 14 to 28 days of age, diets containing 18.5 per cent protein of which 12 per cent is provided by the test supplement and the remainder by cereals with the inclusion of a small quantity of yeast. The total protein efficiency (TPE) of the test supplement is calculated as the weight gain of the chicks divided by the total weight of the protein (supplement, cereals and yeast) eaten by the chicks.

The method is flexible and the diets used allow the testing of supplements varying in crude protein content from 20 to 100 per cent. Reproducibility of results and discrimination between samples is good. The method is particularly adapted to examining the supplementary values of proteins whose inability to support satisfactory growth unaided precludes their evaluation by a normal PER procedure.

Exploratory experiments to study the influence of various factors upon performance are described.     

Large colon resection

With large colon resection and anastomosis, up to 95 per cent of the length of the large colon has been successfully removed. A hand-sewn end-to-end anastomosis is effective for lesions in the left dorsal colon and pelvic flexure. Transection and a side-to-side anastomosis with stapling equipment is most effective for extensive resections (greater than 50 per cent). Horses with extensive colon resection (95 per cent) have permanent deficiencies of water absorption and digestion of cellulose and protein. Fermentative capacity is reduced, owing to decreased particulate matter retention time in the smaller capacity colon. These deficits are minimized with alfalfa hay as the source of forage (fed at 2 per cent of the body weight), and normal blood variables and body weight can be maintained. Voluntary intake increases to help maintain a positive nutrient balance. Grass hay, owing to the higher cell wall content, is inadequate as the sole source of energy and protein, and weight loss will occur. Ad libitum intake of water is recommended at all times, owing to the increased fecal water loss.     

Hydrolyzed protein diets for dogs and cats.

The primary aim of a hydrolyzed protein diet is to disrupt the proteins within the diet sufficiently to remove existing allergens. Published assessment of hydrolyzed protein diets includes physiochemical and immunologic assays as well as nutritional and clinical feeding trials. Potential problems include poor palatability, hypoosmotic diarrhea, and a reduced nutritional value, although persistent allergenicity is the most significant. The primary indications for a hydrolyzed protein diet are use in elimination trials for the diagnosis of adverse food reactions, and the initial management of inflammatory bowel disease. Initial studies of hydrolyzed diet efficacy are encouraging. Consideration of the source ingredients should be given when using hydrolyzed protein diets in elimination feeding trials because antigenic sites may not be fully destroyed.     

The effects of early and late maturity on the protein requirements of pullets

Growing pullets were exposed to two light patterns which caused a difference in sexual maturity of 5 weeks. From 28 to 38 weeks of age they were fed diets containing crude protein levels of 7.0, 8.5, 10.0, 11.5, 13.0 and 14.5 per cent. Yellow maize provided 45 per cent and soyabean meal 55 per cent of the protein in all six diets.

Rate of lay, egg weight and body weight were greater in the late maturing flock than in the early flock at the start of the assay and throughout the assay period. The late maturing pullets required more protein to reach and maintain their maximum potential than the early birds, presumably because their potential output was greater. The late birds showed a diminishing but continued response to protein up to the highest level fed (14.5 per cent corresponding to 23 g. protein per bird day). The early maturing pullets showed no response to dietary protein levels beyond 11.5 per cent and their estimated protein requirement was about 16 g. per bird day.

When limiting amounts of protein were fed (7.0–10.0 per cent of the diet) the two flocks achieved similar levels of egg output. In both flocks and throughout the assay, body weight and egg weight fell at the two lowest levels and increased at the three highest levels of protein.

It is concluded that the protein requirements of early maturing and late maturing flocks of pullets may differ, but only in a way which corresponds directly with their different potential outputs. In the late flock, which had the higher protein requirement, excellent production was obtained with a diet containing 14½ per cent crude protein all of which came from vegetable sources.     

Effects of level of dietary protein and exercise on growth rates of horses

Rates of growth were measured in two-year-old (Experiment 1) and nine-month-old (Experiment 2) horses fed high (12 or 14 per cent) or low (6 or 8 per cent) crude protein diets with one of two levels of exercise (0 or 12 km trotting per day at 12 km/h). In the non-exercised horses feed intakes and growth rates were greater on the high than on the low protein diets. Exercise increased feed intakes and growth rates of horses on the low but not the high protein diets, so that in the exercised groups there were no significant differences in feed intakes or growth rates between the horses on the two dietary protein levels. Exercise increased the apparent digestibility of dry matter, energy and crude protein. There were no differences in skeletal characteristics caused by either dietary protein level or exercise. These results suggest that the growing horse, if exercised regularly, may be given a diet of lower protein concentration than currently recommended without significant reduction in growth rate.     

Use of low protein grower diets to delay sexual maturity of broiler breeding males 1

Two experiments were conducted to determine the effects of delaying sexual maturity of broiler breeder males on subsequent reproductive performance. Four dietary protein levels (16.0, 12.4, 8.9 and 5.1 per cent) were fed during the growing period. Thereafter, all males were fed a diet containing 17.0 per cent protein.

Sexual maturity was delayed 4 and 8 weeks, respectively, by feeding the 8.9 and 5.1 per cent protein diets, but was not affected by feeding the 12.4 per cent protein diet. Viability was superior for males receiving the diets containing 8.9 or 5.1 per cent protein. The low protein diets had no adverse effects on semen production, fertility or hatchability following recovery from the protein restriction.