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PubMed1990

Effect of marketing treatments and transportation on feeder pig performance.

During four 6-wk trials, 376 university-raised, crossbred feeder pigs were used to determine the effects of fasting (no feed or water) vs providing feed plus water or water alone at the simulated market and a 563-km transport on shrinkage and subsequent health and performance. Providing feed and water or water alone during a 12-h market simulation for Trials 1, 2 and 4 or a 24-h period for Trial 3 did not affect subsequent rate of gain (ADG) or feed efficiency (F/G) compared with pigs fasted during the market stay. However, overall shrinkage (market phase plus transportation) of pigs provided feed and water at the market was less (P less than .05) than for fasted pigs (4.0 vs 8.4% for Trials 1, 2 and 4; 4.5 vs 11.8% for Trial 3). Transporting the fasted or nonfasted feeder pig 563 k did not affect subsequent health or performance. Overall shrinkage of the fasted pigs that were transported 563 km vs those that were not transported during Trial 4 was not different (8.8 vs 9.1%; P greater than .05). In conclusion, one-owner feeder pigs can cope with the stress of fasting and transporting long distances without any extended detrimental effects on subsequent health and performance.

Animals↗

PubMed1995

Effect of monensin and monensin and tylosin combination on feed intake variation of feedlot steers.

A trial involving four commercial feedlots and an individual feeding trial evaluated the effect of monensin and monensin/tylosin on intake variation and deaths from digestive disorders. Four commercial feedlots in Texas and Colorado fed 2,904 yearling crossbred steers (340 kg) high-grain diets containing approximately 82% grain, 8% silage and alfalfa hay, 4% fat, and 6% supplement (DM basis). Steers were allotted randomly to one of three monensin/tylosin levels: 1) no monensin or tylosin (control); 2) 22 mg/kg of monensin and 11 mg/kg of tylosin; or 3) 33 mg/kg of monensin and 11 mg/kg of tylosin. Monensin/tylosin reduced DMI (P < .05) and improved ADG (P < .05) and feed efficiency (P < .01). Intake variation associated with dry matter offered per pen was not different among treatments. In the individual feeding trial, feeding 27 mg/kg of monensin reduced (P < .10) DMI variation during grain adaptation and during d 57 to 70 and d 97 to 110 compared with the control (no monensin) diet. The magnitude of intake variance was 5 to 10 times greater with individually fed steers than with steers fed in the commercial feedlot pens. When the DMI of the individually fed steers were averaged and treated as a pen of steers, DMI variance was reduced drastically and was not different between treatments. We interpret these data to indicate that monensin and monensin/tylosin reduce feed intake variation among individual steers within a pen of steers. Pen means mask individual animal variation to the point that it is difficult to detect treatment differences.

Animals↗

PubMed2002

Growth performance, diet apparent digestibility, and plasma metabolite concentrations of barrows fed corn-soybean meal diets or low-protein, amino acid-supplemented diets at different feeding level.

Two experiments, each with 36 barrows with high-lean-gain potential, were conducted to evaluate apparent nutrient digestibilities and performance and plasma metabolites of pigs fed corn-soybean meal diets (CONTROL) and low-protein diets. The low-protein diets were supplemented with crystalline lysine, threonine, tryptophan, and methionine either on an ideal protein basis (IDEAL) or in a pattern similar to that of the control diet (AACON). Amino acids were added on a true ileally digestible basis. The initial and final BW were, respectively, 31.5 and 82.3 kg in Exp. 1 and 32.7 and 57.1 kg in Exp. 2. In Exp. 1, the CONTROL and IDEAL diets were offered on an ad libitum basis or by feeding 90 or 80% of ad libitum intake. Pigs were fed for 55 d. In Exp. 2, the CONTROL, IDEAL, and AACON diets were offered on an ad libitum basis or by feeding 80% of the ad libitum intake. Pigs were fed for 27 d. Pigs fed the CONTROL diet had greater (P < 0.05) ADG and feed efficiency (G/F) than pigs fed the IDEAL (Exp. 1 and 2) and AACON diets (Exp. 2). As the level of feed intake decreased, ADG decreased (P < 0.05), but G/F tended to improve (P < 0.10) for pigs fed 90% of ad libitum in Exp. 1 and for pigs fed 80% of ad libitum in Exp. 2. In Exp. 1, the apparent total tract digestibilities of DM and energy were greater (P < 0.01) for pigs fed the IDEAL diet than for pigs fed the CONTROL diet. In Exp. 2, the apparent total tract digestibility of protein was greatest in pigs fed the CONTROL diet (P < 0.05) and was greater (P < 0.05) in pigs fed the AACON diet than in pigs fed the IDEAL diet. Plasma urea concentrations were lower in pigs fed the IDEAL diet than in pigs fed the CONTROL diet, regardless of feeding level. For pigs fed the CONTROL diet, plasma urea concentrations were lower when feed intake was 80% of ad libitum (diet level, P < 0.01). In summary, pigs fed the IDEAL and the AACON diets gained less and had lower plasma urea concentrations than pigs fed the CONTROL diet. Based on these data, it seems that the growth potential of pigs fed the IDEAL and AACON diets may have been limited by a deficiency of lysine, threonine, and(or) tryptophan and that the amino acid pattern(s) used was not ideal for these pigs.

Amino Acids↗

PubMed2007

Growth performance and ileal and total tract amino acid digestibility in broiler chickens fed diets containing bacterial protein produced on natural gas.

A total of 180 broiler chickens were fed 1 of 3 diets from day-old to slaughter at 35 d: a control diet with 35% soybean meal (SOY) or diets in which either 6% basic bacterial protein meal (BBP) or 6% autolysed bacterial protein meal (AUT) partially replaced soybean meal protein. Ileal and total tract apparent amino acid digestibility were examined in 5 chickens per diet using TiO(2) as an inert marker. Chickens fed the diets with bacterial protein had higher weight gain and feed consumption than control chicks during the first 3 wk, but there were no differences in growth or feed intake during the last 2 wk or during the total experimental period. The birds fed the BBP diet showed more efficient feed conversion compared with chickens fed the SOY and AUT diets. Litter quality at 5 wk was poorer in pens where the chickens were fed the AUT diet compared with the other 2 treatments. There were no differences among diets in the dressing percentage. Ileal amino acid digestibility at 5 wk of age revealed only minor differences between diets. There was a tendency toward lower ileal digestibility (0.12 > P > 0.07) of Arg, Lys, Met, and Phe in the AUT diet compared with the SOY diet, whereas there were no differences between the SOY and BBP diets. Total tract amino acid digestibilities at 5 wk were similar or slightly lower than the ileal digestibilities within diets. Total tract amino acid digestibility at 2 wk was similar to the total tract amino acid digestibility at 5 wk. The diets containing bacterial protein showed lower total tract digestibility of most amino acids compared with the SOY diet. It was concluded that 6% of either basic or autolysed bacterial protein can replace soybean meal in diets for broiler chickens without impairing growth performance, and the basic bacterial protein seemed to be a slightly better substitute than the autolysed bacterial protein.

Amino Acids↗

PubMed1998

Performance and metabolic responses of young dairy calves fed diets supplemented with chromium tripicolinate.

Forty-two Holstein calves were used to study performance and metabolic responses when milk replacer and then postweaning starter were supplemented with 1 ppm of Cr as Cr-tripicolinate. From birth through 8 wk of age, supplemental Cr tended to improve the growth performance of bull calves but not of heifer calves. Starter intake and feed efficiency were not affected by supplemental Cr. From 1 to 5 wk of age, plasma cortisol concentrations sampled just prior to feeding decreased, and concentrations of insulin-like growth factor-I increased. All calves appeared to become less sensitive to insulin as they aged. From 1 to 5 wk of age, plasma glucose and insulin concentrations gradually diverged for all calves; glucose concentrations decreased, and insulin concentrations increased. In addition, glucose clearance rate, measured by i.v. glucose tolerance tests, was more rapid when calves were 2 wk of age than when calves were 8 wk of age. The glucose clearance rate was greater in heifer calves than in bull calves but was not affected by supplemental Cr. Entry of plasma glucose following an i.v. propionate load was also greater in heifer calves than in bull calves but was not affected by supplemental Cr. Plasma nonesterified fatty acids were lower in calves fed milk replacer or starter supplemented with Cr than in control calves, although this effect diminished as calves aged. This finding was considered to be indirect evidence of enhanced insulin sensitivity in calves fed milk replacer or starter supplemented with Cr. Overall, data suggested that supplemental Cr-tripicolinate had minor effects on the metabolism and growth performance of conventionally managed dairy calves. The most notable effects occurred during the initial few weeks of life.

Aging↗

PubMed1985

Effect of carbonated water on growth performance of cockerels subjected to constant and cyclic heat stress temperatures.

Three growth trials were performed to determine the effect of carbonated water on growth performance of cockerels subjected to heat stress temperatures. In Trial 1, a 2 X 2 X 2 factorial design was used to test growth performance of Columbian crossbred cockerels between 8 and 11 weeks of age. The birds were subjected to either cyclic (day-night) heat stress (H) temperature (29 to 34 C) or cyclic (day-night) moderate (M) temperature (25 to 29 C), fed either a corn soy grower (G) diet or a 20% alfalfa diet (A), and provided with tap (TW) or carbonated (CW) drinking water. In Trial 2, a 2 X 4 X 2 factorial was used to access the effect of CW on growth performance of Hubbard cockerels between 4 and 7 weeks of age. Birds were grown in the M or H cyclic thermal environments with dietary treatments consisting of A, G, A plus 1% sodium bicarbonate (AB) and G plus 1% sodium bicarbonate (GB). In Trial 3, a 2 X 2 factorial was used to test the effect of CW on growth performance of Hubbard cockerels fed the G diet and subjected to either constant heat stress (33 C) or thermoneutral (25 C) temperatures. A 24-hr photoperiod was used in each experiment. In all three trials, heat stress reduced (P less than .05) average daily gain (ADG), feed intake, and feed efficiency (G/F).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1994

Influence of amylase genotypes on growth rate and feed conversion of chickens.

Chickens from two breeds were screened for amylase alleles designated as AmyF and AmyS to establish breeder flocks homozygous for each. Offspring from these flocks were then used to test the hypothesis that AmyF and AmyS amylases differ in their ability to digest cornstarch and wheat starch. The amylase allozymes were found to affect growth and feed conversion performance of the chickens, and the effects were more pronounced in one breed. However, these effects seemed to be more related to specific activity of the amylases than to starch source in the diet. The results indicate that in some breeds of chickens selection for AmyS may improve growth and feed efficiency performance.

Alleles↗

PubMed1988

Feeding, behavioural state and cardiorespiratory control.

The aim of the present study was to examine whether immaturity of cardiorespiratory control corresponds to a less mature behavioural state pattern and/or to less efficient feeding behaviour. Fifty-four infants were observed and data polygraphically recorded for 6 hours; a feeding session was included. It was found that infants with immature cardiorespiratory control spent more time in REM-sleep, less time in the active awake state, and were more likely to be inefficient feeders. In addition, 100 infants were observed for risk signs of sudden infant death syndrome and their parents were asked to answer a questionnaire on the sleeping and feeding behaviour of their infants. The majority of the infants with immature cardiorespiratory control were described as bad feeders but good sleepers. We conclude that gathering information about sleeping and feeding behaviour is useful when screening for immaturity of cardiorespiratory control.

Apnea↗

PubMed1988

Ingestive behaviour and physiology of the medicinal leech.

Ingestion lasts 25 min in Hirudo medicinalis and is characterized by pharyngeal peristalsis which fills the crop. This peristalsis has an initial rate of 2.4 Hz which decays smoothly to 1.2 Hz at termination of ingestion. During ingestion, the leech body wall undergoes peristalsis which appears to aid in filling the crop diverticula. Body peristalsis begins at a rate of 10 min-1 and decreases linearly to 2 min-1 at termination. The body also undergoes dorsoventral flexions when blood flow is occluded. Blood meal size increases slightly with leech size: 8.4 g for 1-g leeches and 9.7 g for 2-g leeches. However, relative meal size decreases markedly with increasing animal size; from 8.15 times body mass for 1-g to 4.80 times for 2-g leeches. When intact leeches were exposed to micromolar concentrations of serotonin, there was an increase in the rate of pharyngeal peristalsis and the size of the blood meals. Leeches excrete the plasma from their ingested blood meals. Excretion is activated during ingestion, which increases feeding efficiency by increasing the proportion of blood cells in the ingestate. Excretion continues for 4-6 days following ingestion, removing all the remaining plasma from the ingestate. Leech ingestion comprises stereotyped muscular movements, secretion of saliva and excretion of plasma. A strikingly similar feeding physiology is seen in the blood-sucking insect Rhodnius, and we suggest that efficient sanguivory may require the convergent evolution of similar ingestive mechanisms.

Animals↗

PubMed2003

Integration of suck and swallow rhythms during feeding in preterm infants with and without bronchopulmonary dysplasia.

The aim of this study was to define quantitative measures for assessing the integration and maturation of suck and swallow rhythms in preterm infants as they relate to each other. Fourteen preterm infants (eight males, six females; gestational age range 26 to 32 weeks) with bronchopulmonary dysplasia (BPD) and an age-matched cohort of 20 infants (10 males, 10 females; gestational age range 26 to 33 weeks) without BPD were studied weekly from time of initiation of oral feeding using simultaneous recordings of nipple and pharyngeal pressure. The integration of suck and swallow rhythms was quantified by using the coefficient of variation (COV) of the suck-swallow dyad interval. Infants without BPD had a significant correlation between increasing postmenstrual age (PMA) and decreasing COV of the dyadic interval (increasing stabilization; r=0.45; p=0.008). In the non-BPD cohort 35 weeks or less PMA, the mean dyadic COV was 0.42 (SD 0.12) versus 0.34 (SD 0.09) in those more than 35 weeks PMA (p=0.039). In contrast, dyadic stability in infants with BPD was not correlated with PMA. Infants with BPD of more than 35 weeks PMA had less dyadic stability (0.45, SD 0.10) than did age-matched controls (p<0.001). Dyadic stability was also correlated with feeding efficiency in the non-BPD group (r=0.46;p=0.007) but not in the BPD cohort. Therefore, ontogeny of rhythmic suckle feeding can be described quantitatively in preterm infants, allowing comparison with at-risk populations. Infants with BPD do not follow predicted maturational patterns of suck-swallow rhythmic integration.

Analysis of Variance↗

PubMed2000

Brown midrib-3 corn silage improves digestion but not performance of growing beef steers.

The brown midrib-3 (bm3) gene mutation has been incorporated into corn plants to potentially improve fiber digestibility. The objectives of this study were to determine the effect of bm3 corn silage on digestion and performance of growing beef steers and to determine whether limiting intake would further enhance fiber digestibility of bm3 corn silage. A bm3 hybrid and its isogeneic normal counterpart were harvested at three-quarters kernel milk line. Neutral detergent fiber, ADF, and ADL were 4.5, 6.9, and 1.9 units lower, respectively, and DM was 5.4 units higher for bm3 than for normal silage. In Trial 1, eight ruminally fistulated Angus crossbred steers (224 +/- 24 kg) were randomly assigned to a 2 x 2 factorial arrangement of treatments in a replicated 4 x 4 Latin square design. Steers had ad libitum feed access or were restricted to 80% of ad libitum intake of diets containing 86% normal corn silage (Control) or bm3 corn silage (BMCS). The remainder of the diets consisted of soybean meal, urea, monensin, vitamins, and minerals. Dry matter intake was greater (P < 0.01) for steers offered ad libitum access to BMCS than for those with ad libitum access to the Control diet. The BMCS treatment resulted in improved (P < 0.05) apparent total-tract digestibility of DM, OM, NDF, and ADF. Mean concentration of total VFA and molar proportions of acetate were increased (P < 0.05) by feeding BMCS. There tended to be a DMI x hybrid interaction (P = 0.16) for apparent total-tract digestibility of NDF. When diets were offered ad libitum, BMCS increased NDF digestibility by 10.5 percentage units compared with Control, but, when DMI was limited, BMCS increased NDF digestibility by 15.8 percentage units. In Trial 2, 128 steer contemporaries of those used in Trial 1 (245 +/- 13 kg) were offered ad libitum access to BMCS or Control diets as used in Trial 1. After a 112-d treatment period, concentrate in the diet was increased, and all steers were fed a common finishing diet. During the 112-d treatment period, steers receiving BMCS consumed 0.45 kg more DM/d (P < 0.05) and had similar ADG (P > 0.10), compared with those steers receiving the Control silage. This resulted in poorer (P < 0.01) feed efficiency for steers receiving BMCS. Finishing phase and overall performance of the steers was not different (P > 0.10) due to treatment. Although feeding BMCS in growth-phase diets resulted in increased daily DMI and improved digestibility of DM and fiber, it did not result in improved steer feedlot ADG compared with Control silage.

Animal Feed↗

PubMed1992

2-Hydroxy-4 (methylthio) butanoic acid as a drinking water supplement for broiler chicks.

Two experiments were conducted to study the effects on chick performance of a commercially available liquid methionine analog [2-hydroxy-4 (methylthio) butanoic acid; HMB] supplied through drinking water. Methionine activities of .025 and .05% were added to drinking water and compared with levels of .03, .06, or .09% included in a low-methionine basal diet from 0 to 21 days of age. Mortality was not significantly altered by any dietary treatment. Neither feed nor water intake was affected adversely by HMB inclusion in drinking water. Only male body weight in Experiment 1 did not respond to HMB feed supplementation. Equivalent levels of total sulfur amino acid intake among water treatments were associated with significantly heavier body weights than the control. In both experiments, body weight and feed efficiency of birds receiving .05% methionine activity as HMB in water were equal or superior to those of groups that received supplemented feed. The results indicate that, under the study conditions, HMB provided in drinking water can be effectively assimilated by broiler chicks, at least through 21 days of age.

Animal Nutritional Physiological Phenomena↗

PubMed2005

Effect of grain processing degree on intake, digestion, ruminal fermentation, and performance characteristics of steers fed medium-concentrate growing diets.

Three trials were conducted to evaluate the effects of degree of barley and corn processing on performance and digestion characteristics of steers fed growing diets. Trial 1 used 14 (328 +/- 43 kg initial BW) Holstein steers fitted with ruminal, duodenal, and ileal cannulas in a completely randomized design to evaluate intake, site of digestion, and ruminal fermentation. Treatments consisted of coarsely rolled barley (2,770 microm), moderately rolled barley (2,127 microm), and finely rolled barley (1,385 microm). Trial 2 used 141 crossbred beef steers (319 +/- 5.5 kg initial BW; 441 +/- 5.5 kg final BW) fed for 84 d in a 2 x 2 factorial arrangement to evaluate the effects of grain source (barley or corn) and extent of processing (coarse or fine) on steer performance. Trial 3 investigated four degrees of grain processing in barley-based growing diets and used 143 crossbred steers (277 +/- 19 kg initial BW; 396 +/- 19 kg final BW) fed for 93 d. Treatments were coarsely, moderately, and finely rolled barley and a mixture of coarsely and finely rolled barley to approximate moderately rolled barley. In Trial 1, total tract digestibilities of OM, CP, NDF, and ADF were not affected (P > or = 0.10) by barley processing; however, total tract starch digestibility increased linearly (P < 0.05), and fecal starch output decreased linearly (P < 0.05) with finer barley processing. In situ DM, CP, starch disappearance rate, starch soluble fraction, and extent of starch digestion increased linearly (P < 0.05) with finer processing. In Trial 2, final BW and ADG were not affected by degree of processing or type of grain (P > or = 0.13). Steers fed corn had greater DMI (P = 0.05) than those fed barley. In Trial 3, DMI decreased linearly with finer degree of processing (P = 0.003). Gain efficiency, apparent dietary NEm, and apparent dietary NEg increased (P < 0.001) with increased degree of processing. Finer processing of barley improved characteristics of starch digestion and feed efficiency, but finer processing of corn did not improve animal performance in medium-concentrate, growing diets.

Animal Feed↗

PubMed1998

Individual variability in state-dependent feeding behaviour in three-spined sticklebacks.

We studied state-dependent feeding behaviour of three-spined sticklebacks, Gasterosteus aculeatus, during several trials of sequential encounters with 6-mm and 8-mm Asellus aquaticus prey. We used stomach fullness (the number of prey eaten previously) as an indicator for state, which we assumed to affect motivation for feeding. Dummy variable regression was used to study how the per trial energy consumption, the number of events experienced, feeding efficiency and the average time spent on each accepted prey depended on trial number, day and fish. A clear individual variability was found. Feeding behaviour was strongly related to the individual's recent feeding history (within a day). Logit regression models showed that the decision to accept or reject a prey encountered depended on the size of the fish as well as its state (stomach fullness). Although limited, our results demonstrate pronounced heterogeneity in feeding behaviour among individual fish. We discuss this phenomenon in the broader context of population regulatory mechanisms. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗

PubMed1988

Effects of diet composition on food intake and carcass composition in rats.

Since most of the weight-reduced obese humans are in a protein deficit state, this study was designed to examine whether a high protein diet (HP) enhances the restoration of lean body mass and facilitates the maintenance of weight loss. Obesity in rats was produced by 16 weeks of high fat diet (HF) feeding. In the 17th week, all HF-fed obese rats were fed a limited amount of control diet to normalize their body weights, but they still had more body fat content. The HF-fed rats were then divided into subgroups with different diets offered for 5 weeks: HP, HF or chow diet. A control group was fed the chow diet throughout the study. HP feeding maintained normal body weight and carcass composition in weight-reduced obese rats by reducing feeding efficiency levels to within normal ranges. Weight-reduced rats fed a chow diet, however, had more fat mass than controls and HF feeding stimulated weight gain again. Therefore, a HP diet has a higher probability of enhancing weight loss maintenance in weight-reduced obese subjects than does a usual well-balanced diet.

Adipose Tissue↗

PubMed2005

Arousal and re-feeding rapidly restores digestive tract morphology following aestivation in green-striped burrowing frogs.

During aestivation, the gut of the green-striped burrowing frog, Cyclorana alboguttata undergoes significant morphological down-regulation. Despite the potential impact such changes might have on the re-feeding efficiency of these animals following aestivation, they appear to be as efficient at digesting their first meals as active, non-aestivating animals. Such efficiency might come about by the rapid restoration of intestinal morphology with both arousal from aestivation and the initial stages of re-feeding. Consequently, this study sought to determine what morphological changes to the intestine accompany arousal and re-feeding following 3 months of aestivation. Arousal from aestivation alone had a marked impact on many morphological parameters, including small and large intestine masses, small intestinal length, LF heights, enterocyte cross-sectional area and microvilli height and density. In addition, the onset of re-feeding was correlated with an immediate reversal of many morphological parameters affected by 3 months of aestivation. Those parameters that had not returned to control levels within 36 h of feeding generally had returned to control values by the completion of digestion (i.e. defecation of the meal). Re-feeding was also associated with several changes in enterocyte morphology including the incorporation in intracytoplasmic lipid droplets and the return of enterocyte nuclear material to the 'active' euchromatin state. In conclusion, morphological changes to the gut of aestivating frogs which occur during aestivation are transitory and rapidly reversible with both arousal from aestivation and re-feeding. The proximate causes behind these transitions and their functional significance are discussed.

Animals↗

PubMed1994

Effects of restricted feeding on growth performance and carcass composition of lambs.

Fifty-eight crossbred lambs (26 kg BW) with moderate growth potential were used in a completely randomized design experiment to determine the effects of restricted feeding of all-concentrate diets on performance and carcass composition. Feeding levels studied were 100, 85, and 70% of ad libitum intake. Diets that were restricted-fed were formulated to have increased nutrient concentrations to provide equal daily intakes of protein, vitamins, and minerals among DM intake levels. Lambs were fed to a final weight that would yield carcasses of equal weight (24 kg). Average daily gain was reduced linearly (P < .02) and days on feed were increased linearly (P < .02) because of restricted feeding. Feed efficiency, however, was not affected by intake level. The quantity of separable lean tissue within carcass sides was increased (P < .05) with restricted feeding. Total separable fat within the side was reduced (P < .05) in an amount equal to the increase in lean tissue accretion. Chemical analysis of the carcass side showed a decrease (P < .05) in fat percentage and a corresponding increase (P < .05) in water percentage because of restricted feeding. Daily accretion rates of lean and bone tissue were not affected by restricted feeding; however, fat accretion was decreased linearly with decreasing feeding levels. Separable lean tissue within the primal cuts was generally increased with decreasing intakes, which led to a corresponding decrease in separable fat. Restricted feeding strategies can lead to the production of leaner carcasses. Reductions in fat content occur in the subcutaneous, seam, and mesenteric depot sites, but intramuscular fat content of consumable product also is reduced.

Animal Feed↗

PubMed1987

Feed and water consumption and performance of male and female broilers fed salinomycin and maduramicin followed by a withdrawal ration.

A 3 x 2 factorial floor pen experiment was conducted to determine the effects of feeding salinomycin (60 ppm) or maduramicin (5 ppm) for 49 days followed by a 3-day withdrawal ration upon both male and female broiler chickens in a coccidia-free environment. Body weights, feed intake, and water consumption were recorded at 28, 49, and 52 days of age. Feed efficiency and overall mortalities were also measured. Inclusion of either ionophore into the ration had no effect on final body weight, but improved feed conversion (P less than .05). Birds fed maduramicin drank more than the nonmedicated birds (P less than .05), which in turn, drank more than the birds fed salinomycin (P less than .05).

Animals↗