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PubMed1978

Effects of undernutrition in neonatal rats on physical development and food and water regulation.

The effects of neonatal undernutrition in rats on food and water regulation, external indices of development, and long-term regulatory behavior were investigated. Undernutrition produced retardation in some external indices of development. The ability to eat, drink, and maintain body weight at weaning were not seriously affected by the undernutrition. Longer term deficiencies in feeding efficiency, osmotic regulation, prandial drinking, and activity were found for experimental subjects. The involvement of peripheral-systemic factors as well as neurological retardation in producing feeding and drinking deficits following undernutrition are discussed.

Animal Nutritional Physiological Phenomena↗

PubMed1992

Feeding behavior and brain acetylcholinesterase activity in bream (Abramis brama L.) as affected by DDVP, an organophosphorus insecticide.

1. Bream (Abramis brama) were exposed to sublethal concentration of organophosphorus insecticide DDVP and the amount of food consumed and brain acetylcholinesterase (AChE) examined in exposed fish. 2. Exposure to DDVP resulted in decreased amount of food consumed and inhibited brain AChE activity. 3. Intraperitoneal injection of the fish with cholinergic drugs, atropine and TMB-4 recovered the feeding efficiency in exposed fish. TMB-4 recovered brain AChE activity as well. 4. The results revealed that cholinergic system in fish brain constitutes biochemical mechanism controlling feeding behavior in fish.

Acetylcholinesterase↗

PubMed1995

[Incorporation and mobilization of vitamin A in laying hens].

216 laying hybrids were given diets with 1500, 3000 or 6000 IU vitamin A kg-1 between their 21st and 64th week of age. The ration did not contain any vitamin A between the 5th and 16th as well as the 25th and 28th week. The control animals were fed a diet with 6000 IU kg-1. Feed consumption, laying performance, egg weight, feed efficiency, mortality and the vitamin A content in egg yolk and liver depend on the vitamin A supply. 4-week depletion took an adverse effect on feed intake and laying performance. It was not possible to detect vitamin A in the egg yolk after 4 weeks and in the liver after 16 weeks of depletion.

Aging↗

PubMed1996

Food and water intake as functions of resource consumption costs in a closed economy.

In two experiments, rats living in a closed economy were offered continuous, concurrent access to four resources: food, water, a nest, and a running wheel. Costs of consuming food and water were imposed with bar-press requirements, and the price of either one or both resources was raised. As the consumption cost increased, less was consumed in each bout of resource use. Bout frequency increased, but not sufficiently to compensate for the fall in bout size, and total intake fell. Food and water tended to be complementary resources, in that as intake of one fell with its price, intake of the other also decreased. This interaction was accounted for by the defense of the ratio of body water to lean body mass. As amount consumed decreased, increases in feed efficiency (weight gain per unit of food ingested) and the use of stored calories compensated for the reduced energy intake. There was evidence of competition between feeding and drinking at the higher costs: When both commodities were expensive, the decline in the intake of each one was greater than when only one commodity was expensive. Although the time spent nesting, running, and in unmonitored activity was adjusted when feeding or drinking took more of the rat's day, there was no particular activity that was sacrificed.

Animals↗

PubMed1992

Effects of nicarbazin on intestinal digestion and absorption of nutrients in the rabbit.

Nicarbazin is an anticoccidial drug, used mainly in birds, which has shown several other effects including inhibition of growth and feed efficiency in poultry, and stimulation of sugar and amino acid intestinal absorption in rabbit. The present work was designed to determine whether nicarbazin added to the feed, affects growth and feed intake in rabbit, and whether the continuous ingestion of nicarbazin can alter the mechanisms of intestinal nutrient absorption or digestion in this species. Nicarbazin, administered at the recommended dose (125 ppm) had no harmful effects either on growth or on feed intake of animals. After treatment for one month with nicarbazin at the dose of 125 ppm added to the feed, rabbits displayed a higher transport ability of both D-glucose and L-leucine through the enterocyte plasma membranes than did untreated rabbits. These animals also showed higher specific activities of two brush-border enzymes, sucrase and aminopeptidase N, than the control animals.

Administration, Oral↗

PubMedDate not supplied

Eimeria mitis: immunogenicity and cross immunity of two isolates.

The ability of two isolates of Eimeria mitis to provide protection against homologous or heterologous challenge was examined. Based on weight gain and feed efficiency of male chickens, the B4 and C2 isolates protected against both homologous and heterologous challenge. The unprotected chickens suffered severe growth depression and impairment of feed utilization. Birds were inoculated with a series of increasing immunizing doses and became immune by the sixth dose. The C2 isolate (strain) appeared to be more immunogenic than the B4 isolate (strain).

Animal Feed↗

PubMed1992

Bioavailability of methionine-hydroxy-analog free acid and S-methyl-methionine in the growing rat.

The biological utilization of DL-methionine (MET), DL-methionine-hydroxy-analog and DL-S-methyl-methionine-sulphonium-chloride (SMM) was tested in rat growth assay. Weight gain, feed efficiency, protein efficiency ratio (PER), net protein ratio (NPR) and net protein utilization (NPU) were applied as criteria. A test diet containing soybean meal as sole protein source was fortified with MET, MHA or SMM at 1.5 and 3.0 g/kg levels, respectively. All fortifications had a significant (p < 0.05) positive influence on weight gain, feed conversion and protein utilization. SMM showed the highest activity. MET and MHA were almost equally well utilized at 3.0 g/kg fortification level, however MHA proved slightly less efficient at 1.5 g/kg level than MET.

Animal Feed↗

PubMed2003

Muscle insulin binding and plasma levels in relation to liver glucokinase activity, glucose metabolism and dietary carbohydrates in rainbow trout.

Rainbow trout were fed for 10 weeks with either a carbohydrate-free diet (C-free) or with four experimental diets containing various levels (20 or 40%) and sources of starch (extruded wheat or peas) in order to examine metabolic utilisation of dietary vegetable carbohydrates and its endocrine control. The study was focused on the parameters described as limiting in glucose metabolism in fish. Feeding trials were conducted at 8 and 18 degrees C to establish whether carbohydrate-rich diets can be used in trout farming irrespective of water temperature. At both temperatures, pea diets (especially the highest level) resulted in a feed efficiency as high as the C-free diet. Fish had similar growth rates except when fed the low wheat content diet. Glycaemia values 6 h after feeding were significantly higher in trout fed carbohydrate diets than those given the C-free diet, whereas plasma insulin levels were similar independently of the levels of dietary starch. This study provides the first evidence that glucokinase (GK) activity and mRNA level in trout liver increase in proportion to the content of dietary starch. Nevertheless, these changes were not correlated with plasma insulin levels. Insulin-like growth factor-I (IGF-I) binding and number of receptors in skeletal muscle were consistently higher than those for insulin but no diet-induced differences were found for any of these parameters. Temperature clearly affected the postprandial profile of glucose and insulin, which both showed lower levels 6 h after feeding at 8 degrees C than at 18 degrees C, which was consistent with a lower feed intake. Glucose and insulin levels decreased markedly 24 h after feeding at 18 degrees C, while they were still high at 8 degrees C, an observation concordant with delayed transit rate. These findings indicate satisfactory adaptation of rainbow trout to diets with a relatively high vegetable starch content, especially when provided as extruded peas, and indicate that diets with increased levels of carbohydrates can be used in this species even when it is reared at low temperature.

Animals↗

PubMed2001

Effects of mulberry leaves to replace rapeseed meal on performance of sheep feeding on ammoniated rice straw diet.

This study was conducted to investigate effects of leaves of mulberry tree (Morus alba) as a protein supplement to isonitrogenously replace rapeseed meal (RSM) on performance of growing lambs offered ammoniated rice straw (ABRS) (Trial 1), and to evaluate the digestive characteristics of the ABRS supplemented with different ratios of RSM and mulberry leaves in terms of in vitro gas production (Trial 2). In Trial 1, 45 Huzhou lambs were divided into five equal groups according to their body weight and gender. Lambs in each group were kept in three pens (male, female and mixed (one male and two females)), and received one of the following dietary treatments: 100g RSM (A), 75g RSM plus 60g mulberry leaves (B), 50g RSM plus 120g mulberry leaves (C), 25g RSM plus 180g mulberry leaves (D), and 240g mulberry leaves (E). All animals were given ABRS ad libitum along with 100g ground corn per head per day. The intake of ABRS was slightly increased with the supplementary level of mulberry leaves, and hence total intake increased with the increasing level of mulberry leaves. The growth rates were higher in diets A and E than those in other treatments (P<0.05), with little difference between diets A and E, and the slowest in C. Animals of all genders showed a similar trend, though male lambs was higher in weight gain than the female. While feed efficiency was higher in diet A, concentrate consumption per kilogram of weight gain was lower when higher level of mulberry leaves was supplemented (diets D and E). Feed cost per kilogram gain was lower in diets E and A compared to other treatments. Degradation of dry matter in the rumen of sheep were higher for mulberry leaves than for RSM, but crude protein was less degraded for mulberry leaves than for RSM. The potential GP was significantly higher in diet A than those in B, C and D (P<0.05), and higher in E than in C (P<0.05) (Trial 2), indicating a negative associate effect of mulberry leaves and RSM on digestion. It is inferred that mulberry leaves may be used as a protein supplement to ammoniated straw diets to fully substitute for RSM, but these two supplements should unlikely be supplemented together to avoid the negative associate effect.

Journal Article↗

PubMed2003

Growth and hepatic acetyl coenzyme-A carboxylase activity are affected by dietary protein level in European seabass (Dicentrarchus labrax).

Two trials were undertaken with European seabass (Dicentrarchus labrax) to estimate the protein requirements for maintenance and growth as well as the effect of dietary protein level on the activity of hepatic acetyl coenzyme-A carboxylase (ACoAC). Six diets were formulated to contain graded levels of protein (from 5 to 55% crude protein (CP)) at a constant (12%) lipid level. Three other diets were also formulated to contain 35, 45 and 55% CP, but with a higher lipid level (19%). Groups of 10 individually marked fish (IBW: 100 g) and groups of 8 fish (IBW: 160 g) were used in trial I and II, respectively. Fish were fed to visual satiety and intake was recorded. At the end of both studies, whole body, liver and plasma samples were withdrawn for analyses. Growth rate was improved with increasing dietary CP level. Despite not being the object of a statistical analysis, feed efficiency tended to be enhanced at higher dietary CP level and protein efficiency ratio tended to decrease with increased protein intake. The reduction of the dietary protein/energy ratio, due to the increase of dietary lipids further improved growth and feed utilisation. Data from both experiments indicate 4.5+/-0.5 g kg(-1) d(-1) as the daily protein intake for maximum N gain and 520+/-50 mg kg(-1) d(-1) as the maintenance needs for nitrogen balance. An increase of dietary CP level, up to 25%, increased ACoAC activity. A further increase in dietary CP level (35 to 55%) did not affect liver ACoAC activity. The increase in dietary lipid level depressed significantly liver ACoAC specific activity.

Acetyl-CoA Carboxylase↗

PubMed2002

Digestibility by dairy cows of monosaccharide constituents in total mixed rations containing citrus pulp.

Ten lactating cows were divided into two groups and individually fed ad libitum one of two experimental total mixed rations (TMR) as follows: 1) a TMR containing 20% corn grain and 10% dry citrus pulp (high corn); and 2) a TMR containing 21% citrus pulp and 9% corn grain (high citrus pulp). Both TMR also contained corn silage (28%), legume haylage (19.5%), extruded full fat soybeans (13.5 to 14%), soybean meal (6.5%), and minerals and vitamins. Voluntary dry matter intake of cows consuming the high corn ration tended to be higher than for cows in the high citrus pulp group (22.2 vs. 20.7 +/- 1.0 kg/cow per day, respectively). Digestibility of NDF was higher for the TMR with high citrus pulp compared with the TMR with higher corn. Across treatments, neutral detergent fiber (NDF) glucose was more digestible than NDF xylose and uronic acids and less digestible than NDF arabinose, galactose, and mannose. Digestibility of total neutral detergent soluble carbohydrates was also higher in the high citrus pulp group (86.8, high citrus pulp vs. 80.3 +/- 1.7%, high corn); with glucose and uronic acids accounting for most of that difference. Consequently, higher total carbohydrate digestibility was obtained in the TMR containing higher citrus pulp compared with the TMR with a higher percentage of corn (77.1 and 72.5 +/- 1.0%, respectively). Slightly lower carbohydrate intake in cows fed higher citrus pulp was compensated by higher digestibility of carbohydrates and protein. Thereby, partial replacement of corn by citrus pulp in TMR of high producing dairy cows improved feed efficiency.

Animal Feed↗

PubMed1980

Ammonia versus urea-treated silages with varying urea in concentrate.

In four factorial experiments, 96 lactating Holstein cows averaging 100 days postpartum were fed corn silage (21 to 31% dry matter) ad libitum treated with aqueous ammonia (.3 to .4%) or urea (.5 to .7%). Concentrates fed at 1 kg/3 kg milk contained 0, .7, or 1.4% urea in Experiment 1 and 0 or 1.4% in Experiments 2, 3, and 4. Following 14-day pretreatment, experimental rations were fed for 65 days in Experiment 1 and 84 days in Experiments 2, 3, and 4. Urea in grain and urea in silage depressed intakes of silage and total dry matter. Milk persistences were lowered only by the diet containing urea in both grain and silage. Bodyweight changes, percent milk fat, and feed efficiencies were not altered significantly by treatments.

Ammonia↗

PubMed1975

Anthelmintic treatment of subclinical parasitism of feedlot cattle in Georgia.

Forty heifer calves, 27 yearling heifers, and 64 yearling steers with naturally occurring infections of nematode parasites were treated with levamisole HCl or morantel tartrate or were not treated. Although heifer calves had much larger worm egg counts before treatment than yearling heifers, necropsies showed a smaller average number of nematodes in the calves. Both anthelmintics significantly reduced the egg counts. At the end of the experiments, 98 to 240 days after treatments, there was no significant difference among groups of cattle in respect to necropsy worm counts. An advantage of 5% in rate of gain in body weight was shown in each experiment or phase of an experiment in favor of the treated groups of cattle. Overall, an advantage of 6% in feed efficiency was calculated for the treated groups of cattle.

Animal Feed↗

PubMed2004

Sim1 gene dosage modulates the homeostatic feeding response to increased dietary fat in mice.

Haploinsufficiency of the transcription factor gene Sim1 has been previously implicated in hyperphagic obesity in humans and mice. To investigate the relation between Sim1 dosage and hyperphagia, we generated sim1-knockout mice and studied their growth and feeding behavior. Heterozygous mice weaned on standard chow consumed 14% more food per day than controls and developed obesity, hyperinsulinemia, and hyperleptinemia. The sim1 heterozygous mice were also significantly longer than controls. Heterozygous animals had modestly increased feeding efficiency, suggesting reduced energy expenditure, but voluntary wheel-running activity did not differ significantly between the two groups. We studied the effect of dietary fat on the feeding behavior of heterozygous sim1 mutant mice. The tempo and severity of weight gain were much greater in animals weaned on a high-fat diet. When acutely challenged with increased dietary fat, sim1 heterozygous mice weaned on the chow diet markedly increased their food consumption and caloric intake, whereas control mice reduced the mass of food they consumed and maintained approximately isocaloric intake. In wild-type adult mice, we detected Sim1 expression in the paraventricular and supraoptic nuclei, as previously reported in neonates, as well as in the amygdala and lateral hypothalamus, all regions implicated in feeding behavior. Our results indicate that Sim1 gene dosage modulates the homeostatic feeding response to increased dietary fat and likely plays a physiological role in the regulation of energy balance.

Aging↗

PubMed1995

Effect of early nutrient restriction on broiler chickens. 1. Performance and development of the gastrointestinal tract.

An experiment was conducted to determine the effects of early nutrient restriction on performance and development of the gastrointestinal tract of broiler chickens. Four hundred male broiler (Ross x Ross) chicks raised in floor pens were assigned to two treatment groups. One group was given ad libitum access to feed from 1 to 48 d of age. The second group was feed restricted from 7 to 14 d of age to an energy intake of 1.5 x BW.67 kcal ME/d and then given ad libitum access to feed from 14 to 48 d. Body weight and feed intake were determined weekly. At 49 d of age, birds were processed for carcass yield, abdominal fat pad measurement, and body composition analysis. Broilers were also sampled at 7, 14, 21, and 41 d of age for proventriculus, gizzard, small intestine (duodenum, jejunum, and ileum), pancreas, and liver weights and for intestinal length measurements. Total DNA, protein:DNA, and RNA:DNA ratios of livers and jejuna were determined as indexes of changes in cell size and number. Feed-restricted broilers failed to catch up to the Control birds in BW at 48 d of age but were superior (P < .01) in overall feed efficiency. No treatment effects were observed on breast meat yields or abdominal fat. Moreover, percentage carcass fat, crude protein, ash, and dry matter were not affected by restricted feeding. Body weight and weights of gastrointestinal organs were reduced (P < .01) by feed restriction at 14 d of age. Restricted feeding, however, did not decrease the relative weights of organs, except for liver. Feed restriction also resulted in a reduction (P < .01) of liver cell number and size and a decrease in jejunum cell number. All organs recovered normal weight on refeeding, and all cellular constituent ratios (e.g., RNA:DNA, RNA:protein, and protein:DNA) returned to normal by 41 d of age. Absolute and relative weights of supply organs (e.g., proventriculus, gizzard, small intestine, liver, and pancreas) were less affected by feed restriction and responded more quickly to refeeding than the whole body.

Animal Nutritional Physiological Phenomena↗

PubMed1999

Evaluation of raw and heated velvet beans (Mucuna pruriens) as feed ingredients for broilers.

Velvet bean plants (Mucuna pruriens) are used widely outside the U.S. as a cover crop. The beans (VB), high in protein, contain toxic substances that possibly can be destroyed by heating. Few data are available on the use of VB in poultry nutrition. We examined the effects of raw and dry-roasted VB on broiler performance in two experiments. In Experiment 1, 10, 20, and 30% raw VB were substituted into nutritionally balanced rations fed 0 to 42 d of age. Raw VB caused progressive reductions in growth; at 42 d of age, broilers fed 30% VB weighed 39% of controls. Feed intake declined significantly only with 30% VB. Feed efficiency decreased significantly with 20 and 30% VB. In Experiment 2, 10% raw VB and 10, 20, and 30% heated VB were fed 0 to 42 d. With 10% raw VB, broilers grew significantly slower but feed intake was unchanged. Inclusion of 10% heated VB allowed better growth than raw VB, and by 42 d of age, growth was not significantly different from that of controls. At 20 and 30%, heated VB promoted much better growth and efficiency than raw VB in Experiment 1, but values were significantly lower than those of controls. With 30% heated VB, broilers grew to 66% of control, a marked improvement over raw VB. Carcass yield was unaffected. Trypsin inhibitor activity but not L-3,4-dihydroxyphenylalanine (L-DOPA) in VB was destroyed by heating. We conclude that dry heating of VB partially destroys its growth-inhibiting factor(s), allowing successful use of 10% heated VB in broiler rations. Higher levels of heated VB reduced broiler performance, although results were much better than those of raw VB.

Animal Feed↗

PubMed1988

Monensin level during grain adaptation and finishing performance in cattle.

Two finishing trials were conducted to measure the response of cattle adjusting to high-concentrate diets to dietary monensin level. In trial 1, 54 individually fed Hereford-Angus steers (312 kg), previously fed a two-thirds corn silage: one-third corncob-based diet, were allotted in a 2 X 3 factorial arrangement of treatment with tylosin (0, 11 mg/kg) and monesin (0, 11, 33 mg/kg) fed during a 28-d, grain-adaptation period (fed 75% concentrate for 6 d and then fed 95% concentrate). After 28 d, all steers were continued on their respective levels of tylosin and 33 mg/kg monensin for the remaining 119 d. Daily intake patterns indicated digestive upset in all treatments during adjustment to the 95%-concentrate diet. Blood samples taken during the first 28 d revealed no differences in acid-base status in response to monensin level; however, all steers exhibited reduced (P less than .01) pH and HCO3 and increased (P less than .01) lactate after 4 d on a 75%-concentrate diet. In the initial 28 d, intake decreased (linear P less than .05) as the level of monensin increased. In the total finishing period, however, increasing the level of monensin fed during grain adaptation decreased (linear P less than .05) intake and tended to decrease (linear P = .20) gain with no effect on feed efficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Acidosis↗

PubMed2000

Dietary choline requirement of juvenile yellow perch (Perca flavescens).

We conducted an 11-wk feeding trial to determine the dietary choline requirement of juvenile yellow perch (Perca flavescens) and to investigate whether dietary phosphatidylcholine (PC) could meet this requirement. Six dietary treatments contained choline concentrations of <0.11, 0.23, 0.34, 0.75, 1.22 or 3.37 g/kg diet. Two additional diets contained 31 g of lecithin/kg diet, with or without supplemental choline chloride (4.0 g choline/kg diet). The total sulfur amino acid concentration was maintained at 1.0 g/100 g diet (methionine/cyst(e)ine, 49:51). Diets were fed to satiation twice daily to triplicate groups of yellow perch initially weighing 16.0 g/fish. Weight gain, feed intake and carcass proximate composition were significantly affected by dietary choline. Weight gains and feed intakes increased as dietary choline increased from 0 to 0.75 g/kg. Both values tended to plateau in fish fed dietary choline levels above 0.75 g/kg. Broken-line analyses of weight gain and feed intake data indicated the dietary choline requirement was 0.598 and 0.634 g/kg diet, respectively. Hepatic lipid concentrations and feed efficiency values were not significantly different. Whole-body fat concentrations increased significantly, whereas ash levels decreased significantly in fish fed increasing levels of dietary choline. Weight gain and feed intake of fish fed diets containing PC were not significantly different from fish fed 0.75 g/kg of dietary choline. However, hepatic lipid concentrations were significantly higher in fish fed the diet containing PC and no choline chloride. Thus, yellow perch require a maximum of 0.598-0.634 g of choline/kg diet for maximum growth and this requirement may potentially be met with 31 g of lecithin/kg diet.

Analysis of Variance↗