Kg Of Food Research Articles

Bone Consumption by Cheetahs at Undisturbed Kills: Evidence for a Lack of Focal-Palatine Erosion

The feeding behavior of wild and wild-caught, captive cheetahs (Acinonyx jubatus) was observed to determine time spent at kills, the amount of food consumed, and especially, which, if any, bones were consumed. Wild cheetahs stayed with kills up to 11 h. Individual cheetahs consumed up to 10 kg of food in < 2 h. Cheetahs consumed all bones, except the skull, of prey weighing < 10 kg, and consumed a substantial proportion of the rib cage and vertebral column of 30-50-kg prey. Juvenile cheetahs (aged 6-16 months) had no difficulty crushing and consuming bones

Nutrition of Captive Cheetahs: Food Composition and Blood Parameters

AbstractDiet and nutrition of cheetahs was evaluated through survey, in conjunction with chemical analysis of feed and plasma samples, as part of a multidisciplinary effort to investigate underlying causes of low reproductive success in North American captive cheetah populations. Cheetahs consumed an average of 1.32 ± 0.4 kg of food daily, containing approximately 1,800 kcal, and maintained an average body mass of 36.7 ± 1.0 kg (n = 34). A commercially prepared horsemeat‐based mixture comprised the dietary staple in 10 of 13 zoos responding to the survey, with additional whole or carcass portions offered 1‐‐2 days per week to maintain variety and provide periodontal stimulation. Seven of 13 respondents fasted animals 1 day/week; five maintained no fast days. The primary meat product (n = 14 samples) contained: 58% crude protein, 28% crude fat, 7% total ash, 52 Iu/kg vitamin E, 9.7 Iu/g vitamin A, and 2,200 mg/kg taurine (dry basis). Mineral content of the same food item was: 1.9% Ca, 10.0 mg/kg Cu, 645.2 mg/kg Fe, 0.08% Mg, 22.6 mg/kg Mn, 1.3% P, 0.4% Na, and 127.8 mg/kg Zn. Nutrient levels, except vitamin E (and possibly Mg), met or exceeded recommendations established for domestic felids. Plasma α‐tocopherol, retinol, and taurine (18.1, 1.82, 128.4 μmol/L, respectively) concentrations were similar to normals for domestic felids, as were mean plasma mineral levels (n = 81; in mEq/L: 5.64 (Ca), 0.03 (Cu), 0.03 (Fe), 2.0 (Mg), 166.0 (Na), 12.3 (P), and 0.026 (Zn)). No gross physiological or dietary nutrient imbalances were evident from this survey. © 1993 Wiley‐Liss, Inc.

Prey species and nutritive value of food fed during summer to King Penguin Aptenodytes patagonica chicks at Possession Island, Crozet Archipelago

The diet of King Penguins Aptenodytes patagonica at Possession Island was studied in February 1989 by analysis of 20 stomach contents collected from adult birds, just before they fed their single chicks. The mean mass of the samples was 1.84 kg, equivalent to 15% of the unladen adult body‐mass. Fish accounted for 99.8% and squids for 0.2% by mass. The main prey were mesopelagic myctophid fish which live in dense shoals and perform a daily vertical migration. Subadults/adults of Electrona carlsbergi and juveniles and subadults/adults of Krefftichthys anderssoni represented 73.7 and 13.4% of the diet by mass, respectively. No difference was found in the diet of male and female King Penguins. Comparison of individual samples suggests that these birds catch a large quantity of fish from only a limited number of shoals. The mean caloric content of the food was 7 kJ/g wet mass. The total energy requirement of each chick during its initial period of growth was estimated to amount to 328,000 kJ, equivalent to 55 kg of food. The rate at which energy was delivered to the chick was calculated to be 50 W during this period.

Effect of diet on folates levels and distribution in selected tissues of the rat.

A technique for the extraction, purification and concentration of folates, followed by high performance liquid chromatography assay with fluorometric detection of the three principal derivatives (tetrahydrofolic, 5-methyl-tetrahydrofolic and formyl-tetrahydrofolic acids) has been applied to the determination of tissue folates in rats. The levels found are compared to those of the microbiological assay using Lactobacillus casei. When rats were fed a diet containing 1 mg of folic acid per kg of food, levels in the intestinal mucosae, liver, whole blood and brain were 0.59, 14.87, 0.28 and 0.83 nmol/g of tissue. An exogenous supply of 200 mg of folic acid/kg of food significantly increased folate levels in all tissues studied, except for the brain: 1.51, 28.93, 0.52 and 0.99 nmol/g, respectively in the above four tissues. The separation of the various derivatives and a variable supply of folic acid have enabled the conversions of these metabolites to be studied.

Relationship between post-feeding stereotypic behaviour and plasma cortisol in sows

In a previous study (Terlouw et al., 1991, Anim. Behav., 42: 981–991) on the effects of physical restraint and food allowance on the development of stereotypies in pigs (Sus scrofa), it was found that in both restrained and loose-housed pigs low food levels were accompanied by increased levels of total activity, and of chain manipulation and drinking. We have suggested that these activities may have been the expression of high levels of motivation to feed or forage, which in both housing systems were directed to the chain and to the drinker. The present results confirm the effects of food restriction on the development of stereotypies, as also in the second and third parity individuals receiving a low food allowance (2.5 kg of food per day) spent more time being active, performing higher levels of most activities, in particular chain manipulation and drinking, than individuals receiving a high food allowance (4.0 kg day−1). The effects of physical restraint were mostly limited to the low-fed group: low-fed restrained sows were slightly more active, and they performed more drinking and inactive standing than low-fed loose-housed sows. These effects were restricted to certain times of day. The present study was also the first to investigate the behaviour of the same sows over several parities, and it found that overall levels of total activity and of chain manipulation did not increase over parities. Low-fed sows showed, however, a small increase in sham oral activity and drinking-related activity. High-fed sows showed an increase in feeding rate over parities and low levels of chain manipulation. Positive correlations between individual levels across parities indicated that, in contrast to previous suggestions, sows were relatively consistent in their behaviour. In the fourth parity, increasing the food allowance to 4.0 kg day−1 did not reduce stereotypies in previously low-fed sows; reducing food allowance in previously high-fed sows was accompanied by an increase in activity in the longer term. Stereotypies occurred mainly after the meal with post-feeding activities occurring in a specific sequence. High-fed sows performed a short period of nosing and rooting the trough, then drank and lay down. Low-fed sows, in contrast, persisted in their drinking and in addition performed chain manipulation. The behavioural processes that may underlie these effects are discussed.

The Influence of Fatness and Fat Change on the Performance of Breeding Gilts

Weight gains can occur with substantial fat losses and therefore liveweight change is unlikely to form the basis of feeding strategies, whereas the fatness of the animal may be a more appropriate criterion. Eighty Large White x Landrace gilts were first mated at 123.5 kg ± 1.54 with a P2 of 14.5 mm ± 0.24 [Meritronics] and 12.7 mm ± 0.19 (Vetscan]. Half these gilts were fed to be fat [F] at parturition [target 20-24 mm P2) and half were fed to be thin [T] [target 10-14 mm P2). F gilts consumed more feed during pregnancy and gained more weight and backfat than T gilts [all differences between the 2 treatments were significant P˂0.001). The number of piglets born and the number of live births were not affected by feeding gilts to be fat or thin, but fat gilts produced significantly heavier piglets. After parturition, half of both F and T gilts were offered either 7 kg of food per day [H] or 3 kg per day [L] and half were sucked by litters of 5 piglets and half by litters of 10 piglets during a 28 day lactation. Piglets were not given creep feed. Fatness of the gilts at parturition, feed level during lactation and sucking litter size all significantly influenced both the absolute and the change in liveweight and backfat from farrowing to weaning. Weight and P2 changes are shown in Figures 1 and 2. The performance of the litter was also significantly affected by the fatness of the gilt at parturition and by the number of piglets sucking. Results for each treatment group are given in Table 1. Animals offered the high level of feed during lactation had a significantly shorter interval between weaning and conception. There were also positive relationships between readiness to rebreed and absolute liveweight and absolute fatness.

Alimentation artificielle des larves de carpe ( Cyprinus carpio L.)

A batch of 12 000 carp larvae ( Cyprinus carpio L.) issued from a single couple of breeders was reared for 43 days exclusively using artificial food (for 21 days on a diet based mainly on liver and yeast, and on a commercial trout starter feed during the following period). After 24 days of rearing in a tank of 300 l, survival was 87%. After 19 additional days of rearing in a tank of 1500 l, survival was 71% and mean weight 1.16 g. The daily specific growth rate decreased from 23% to 8% during the experiment. Total food conversion ratio was 0.62 (6.08 kg of food was distributed for a final total weight of 9.88 kg of fish). The results presented here indicate that it is possible to rear carp larvae without zooplankton. Exact determination, in the course of rearing, of the total weight of fish and precise adjustment of the quantities of food delivered should allow further improvements in survival and growth.

Solar cookers for outdoors and indoors

The solar cooking process has been investigated to develop safe, simple, portable, and reliable solar cookers. The concept of insulated and vapor-tight pots has been introduced and applied to oven, point-focus and heat-pipe cookers. A new, flat-plate cooker with heat pipes has been developed. It requires no tracking and allows cooking to be done in the shade or indoors. Also, a novel-portable cooker, the Mina Oven, featuring a vapor-tight pot and an integral collector with reflector flaps, has been constructed and tested. A second portable cooker that has been developed is the Arafa Cooker, which comprises a parabolic dish focused at a glazed and insulated receiver. Experiments indicated that all cookers yielded satisfactory performance, with cooking times of 25–45 min per kg of food per m 2 of solar collection area while operating from 10 a.m. to 4 p.m.

Mebendazole and the development of Hymenolepis nana in mice

Normally in mice the intra-villus phase of Hymenolepis nana life cycle is completed by the fifth day of infection. However, when the mice were fed continuously on a mixture of 1.5 g Telmin (166.7 mg of mebendazole/g) per kg of food (Purina Lab Chow) from day 1 (24 h) post infection (p.i.), this intramucosal phase was prolonged for varying periods up to day 12 p.i. Mebendazole expelled successfully all lumen dwelling stages of the parasite, but, when treatment was terminated, cysticercoids still in the villi mucosa were able to recover from the drug's effect on their development, excyst, leave the villi and grow to fully gravid adults in the intestinal lumen.

Energy consumption during cooking

SummaryAn analysis has been made of the energy expended in the cooking of a number of different foods in an electric forced‐convection oven. Out of the total energy used of 1.4 to 1.7 MJ per kg of food, 0.43 to 0.72 MJ was actually absorbed by the food. Most of the balance was lost to the environment as heat. These results are discussed in terms of energy conservation.A feature of the results is the close similarity between the energy absorbed by the food, and the sum of the sensible and latent heats.

Estimate of the volatile nitrosamine content of UK food.

MANY nitrosamines are carcinogenic1 and can be formed by the interaction of nitrite with primary2, secondary3 or tertiary amines4, or even quaternary ammonium salts5. Foods contain many amines, and in cured meats sodium nitrite provides the other precursor for the potential formation of nitrosamines. Some strains of bacteria reduce nitrate to nitrite, so that nitrate in conjunction with the appropriate amine could also lead to nitrosamine formation6. There have been several studies in which cured meats and a few other foods have been examined for nitrosamines, although most of these have been restricted to the detection of the volatile dialkyl and simple heterocyclic compounds7. Combined gas chromatography and mass spectrometry is the most reliable method, and has a typical detection limit of 1 µg per kg of food for volatile nitrosamines. More recently, the chemiluminescent detection of nitrosamines has enabled much lower concentrations to be measured8. We have carried out a survey of foods commonly encountered in the UK, using mass spectrometry9 and chemiluminescence, and we now summarise our data to assess the intake of volatile nitrosamines from these foods.

Growth, food consumption and litter production of female pigs mated at puberty and at low body weights

SUMMARYGilts were allocated at 55 kg live weight to one of three treatments: 1. 1·4 kg of food daily to service, served at puberty, and 1·4 kg of food daily throughout pregnancy.2. 1·4 kg of food daily to service, served at the third heat, and 1·4 kg of food daily during pregnancy.3. 2·3 kg of food daily to service, served at the third heat, and 1·4 kg of food daily during pregnancy.An attempt was made to encourage early puberty by stimulation using the presence of a boar. Natural service with boars was used on all gilts.There were no significant differences between the treatments in time taken to reach puberty and the gilts were mated at 77, 97 and 116 kg live weight on Treatments 1, 2, and 3 respectively. The gilts on Treatment 1 had a significantly lower conception rate and a significantly smaller litter size than those on Treatments 2 and 3. However, the average birth weight did not vary significantly among treatments.

Enzyme induction by polychlorinated biphenyls relative to known inducing agents.

SummaryEnzyme induction by equimolar dietary amounts of DDT, phenobarbital, and PCB was studied in rats after 30 days of treatment. At 150 μmoles per kg of food, PCB was far more effective than phenobarbital and was at least as effective as DDT. At 15 μmoles, phenobarbital, DDT, and PCB produced substrate-specific increases in enzymatic activity.

HUNTING METHODS AND CHOICE OF PREY OF GYRFALCONS FALCO RUSTICOLUS AT MVTN IN NORTHEAST ICELAND

SUMMARYGyrfalcons breeding near Myvatn in northeast Iceland were studied from 1960 until 1970. Hunting methods and successful attacks are described. The Gyrfalcon usually hunts low over the ground and tries to surprise and flush its victim and then stoop upon it. If this fails, it may pursue.The choice of prey was studied by observations from mid‐May to September of Gyrfalcons carrying prey, and by examining food‐remains at eyries. Ducks and Ptarmigan comprised about 49% and 41 % respectively by number of individuals, and 62% and 35 % by estimated fresh weight. One pair utilised some 88 kg of food to raise foui young.The proportion of Ptarmigan in the diet increased during the study, reflecting the increase of the Ptarmigan population and suggesting that Ptarmigan are the preferred prey since waterfowl were abundant all the time.

Breed and sex differences in the growth rates of chicks fed diets supplemented with penicillin.

Synopsis Nine hundred and forty‐seven chicks comprising 490 chicks of heavy type and 457 chicks of light type laying breeds were reared in a series of experiments. Approximately one‐half was fed on a basal ration and the other on this ration plus 55 mg of procaine penicillin per kg of food. An additional 120 chicks, equal numbers of both sexes of both types, were reared on the above‐mentioned rations and half were killed at 3 weeks of age and the other half at 9 weeks so that their intestines could be studied at post‐mortem examination. The male chicks fed the antibiotic grew at a significantly faster rate than the females up to 3 weeks of age, and the weights of 1 cm lengths of the small intestine were significantly reduced by the antibiotic in the male chicks at 9 weeks of age. Type responses were not clearly defined, but there was a significant reduction in the weight of 1 cm lengths of the small intestine at 9 weeks of age in the heavy type chicks when compared with the light type.

Hepatic tumors induced by selenium

Fourty heterozygotic rats received Na2SeO4 (10 mg per kg of food). Out of 23 rats, which survived for over 18 months, the tumors developed in 10: in 3 cases there was cancer of the liver (in 2 rats—metastases into the lungs), in 4—sarcoma, and in 3—hepatic-cellular adenoma. Addition of riboflavinto the diet (10 mg daily), beginning from the 7th month of the experiment, did not change the pathological process. A suggestion is made that the blastomogenic effect of selenium is connected with the fact that it is methionine antimetabolite and the mechanism of its action is possibly very similar to that of ethionine.