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PubMed1988

Broiler performance when reared under various light sources.

Three trials were conducted to determine if modern energy-efficient light sources, which vary in wavelength emission, affect broiler growth performance. The effect of light source on growth performance was determined by measuring body weight, feed conversion, and livability at intervals throughout rearing and at market age in three flocks of approximately 3,600 broilers each. Illuminance within the light-proof experimental facility was approximately 5 1x and photoregimen was 1 h dark:23 h light. Trial 1 compared incandescent (IN), warm white fluorescent (WWF), and daylight fluorescent (DLF) light sources. The WWF source provided superior body weight compared to IN light but feed conversion ratios were similar. Both IN and WWF light sources resulted in better body weight and feed conversion than that of the DLF light source. Trial 2 used IN, WWF, DLF, PL-5 fluorescent (PLF), design white fluorescent (DWF), and high pressure sodium (HPS) light sources. The PLF source resulted in mean body weight significantly higher than those produced by IN, HPS, and DWF. No other significant differences were observed. Trial 3 used IN, WWF, DLF, PLF, HPS, and low pressure sodium (LPS) light sources. Feed conversion for the HPS treatment was superior to that of PLF and LPS treatments. No other significant differences were observed. Light source did not affect livability in any of the trials. These trials demonstrated that energy-efficient light sources varying in wavelength emission may affect broiler growth performance, but consistent differences were not observed. Generally, IN light sources may be replaced with more energy-efficient light sources without adverse effects on broiler growth performance.

Animals↗

PubMed1988

Serologic incidence of Cryptosporidium in Delmarva broiler flocks.

Banked serum samples collected from an industry-wide serologic survey of eighteen Delmarva broiler flocks conducted in 1985 were evaluated for the presence of Cryptosporidium- specific antibodies in an indirect enzyme-linked immunosorbent assay (ELISA). Evaluation of sera collected at 49-days posthatch showed that 38% of the broiler flocks were serologically positive, whereas 50% of samples obtained from flocks at 63-days during an extended growout were positive. From a performance standpoint, the top nine flocks in the study were essentially negative at the 49-day sampling. In order to more firmly establish the serologic prevalence of Cryptosporidium in Delmarva broiler flocks, a second serologic survey was conducted early in 1987. In this study, an estimated 22% of the 454 broiler flocks sampled at approximately 49 days of age were positive for Cryptosporidium. The negative Cryptosporidium serology in the top 25% of these flocks was associated with better performance, but positive Cryptosporidium serology was not clearly correlated with poor performance. Remarkable differences between Cryptosporidium serologic exposure rates of the growout companies were observed, with some companies having exposure rates as high as 40%, and others rates of less than 3%.

Animals↗

PubMed1988

Research note: effects of caponization on broiler growth.

The effect of caponization on growth of male broiler chicks was investigated in two experiments. Broiler chicks were caponized, sham-operated, or left as intact controls at 3 wk of age (Experiment 1) or 1 wk of age (Experiment 2). When processed at 7 wk of age, intact control broilers in both experiments were significantly heavier than sham-operated or caponized broilers, with no significant weight differences between sham-operated and caponized birds. However, the slope of growth rate in capons was significantly greater than that of sham-operated controls in Experiment 2. Capons also had significantly larger abdominal fat pads than did sham-operated controls.

Animals↗

PubMed1988

Use of organic acids in broiler diets.

Two feeding trials were carried out to determine the potential use of fumaric acid and calcium formate in diets for broiler chickens. In the first study using male broiler chicks fed to 21 days of age, fumaric acid was added at 0, .5, 1.0 and 1.5% and calcium formate was added at 0, .72, 1.48, 2.20, and 2.89%. All combinations of fumaric acid and calcium formate were evaluated in a 4 x 5 factorial arrangement of treatments. Addition of .5 or 1.0% fumaric acid significantly (P less than .05) improved body weights of broilers but did not influence feed utilization. Addition of calcium formate at levels greater than .72% significantly reduced both body weight and feed utilization. There was no significant interaction between levels of fumaric acid and calcium formate. In a second trial, male and female broiler chicks were grown to 49 days of age using diets containing 0, .5, 1.0, and 1.5% calcium formate. Addition of .5 or 1.0% calcium formate had no significant effect on weight gains or feed utilization. Addition of 1.5% calcium formate significantly reduced body weights of both males and females at 21 and 42 days. At 49 days of age, body weights of males fed 1.5% calcium formate did not differ from those of males fed the control diet, but were significantly less than those of males fed diets with .5 or 1.0% calcium formate. Female body weights at 49 days of age were significantly depressed by addition of 1.5% calcium formate.

Animals↗

PubMed1989

Influence of the sense of taste on broiler chick feed consumption.

This study was performed to determine the effects of five flavored diets on feed consumption, weight gain, and feed efficiency of broiler cockerels. Isocaloric diets were flavored with .06% saccharin, 6% citric acid, 5% salt, .10% quinine, or .13% aspartame. In Experiment 1, 1-wk-old broiler cockerels were fed an unflavored control diet ad libitum from a divided feed tray for 3 wk. Sides of the feed tray were rotated daily, every other day, or not at all, to determine the effect of position on preference. In Experiment 2, 1-day-old broiler cockerels were offered a choice between an unflavored control diet and a flavored diet, in an ad libitum feeding arrangement, for 3 wk. In Experiment 3, 1-day-old broiler cockerels were offered a choice between two flavored diets fed ad libitum for 3 wk. Daily rotation of the feed tray eliminated preferences due to position. When each side of the feed tray contained the same unflavored diet and was rotated daily, there were no significant differences in feed consumption, weight gain, or feed efficiency. In Experiment 2, there were significant differences in feed consumption between the control diet and all flavored diets except aspartame. The birds offered saccharin, citric acid, salt, and quinine ate significantly less of these diets than of the unflavored control diet. In Experiment 3, the birds detected the differences in flavor and consumed the feed in a specific order of preference: aspartame, saccharin, citric acid, salt, quinine.

Animal Feed↗

PubMed1990

Impact of L-phenylalanine supplementation on the performance of three-week-old broilers fed diets containing ochratoxin A. 1. Effects on body weight, feed conversion, relative organ weight, and mortality.

An experiment with a completely randomized 2-by-3 factorial design was used to study the effects of ochratoxin A (OA; 0 and 4 mg of OA per kg) and supplemental L-phenylalanine (Phe; .0%, .8%, and 2.4% of Phe) in the diets of 3-wk-old broilers. Diets based on ground yellow corn and dehulled soybean meal were fed from Day 1 to 3 wk of age. A total of 240 male Hubbard-by-Hubbard broilers were randomly placed in battery brooders with 10 birds per pen. Each treatment was replicated 4 times. The parameters measured included mortality, BW, feed conversion, and relative organ weight. Broilers receiving OA weighed less and had poorer feed conversions than birds not receiving OA. For broilers receiving OA, the relative weights (grams of organ weight per 100 g of BW) of the liver, proventriculus, gizzard, and heart increased, while the relative weight of the bursa decreased. Supplemental Phe decreased the relative weight of the liver and increased the relative weight of the gizzard and heart. The regression slopes for Phe at 4 mg of OA per kg of diet were significantly different from 0 for BW, the relative weights of the kidney, spleen, and pancreas and approached significance for mortality (P = .065). In the absence of supplemental Phe, 42.5% of the birds died during the study when the dose level was 4 mg of OA per kg of diet. However, when Phe was supplemented at .8 and 2.4%, only 12.5 and 15.0% of the birds died, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Locomotion of broiler chickens in floor pens.

Locomotion has a major effect on production and animal welfare as it relates to feed and water acquisition, feed utilization, carcass quality, health, and physical vigor. The locomotor abilities of the broiler are also important considerations in pen design and placement of feed and water dispensers. To study the locomotion of broiler chickens and the effect stocking density has on locomotion, eight groups of broiler chickens were observed in an experimental floor pen (1.2 by 1.7 m). A Videomex V Image Motion Computer was used to determine the distance traveled and the frame-by-frame (30 frames per s) location of a focal bird. Four densities (660, 790, 990, and 1320 cm2 per bird) were tested, one on each day of the 4-day recording period for each group of birds. Broiler chickens were active throughout the day and traveled an average distance of 8.8 m per h or 212 m per day. Increasing housing density reduced the distance traveled (10, 8.8, 8.5, and 8.1 m per h for 1,320, 990, 790, and 660 cm2 per bird, respectively) but did not affect the average number of visits to the feeders (4 per h) and water cups (2 per h). The focal birds used the total space provided during the day, indicating that they were not consistently socially restricted to certain areas of the pen.

Animals↗

PubMed1990

Influence of dietary supplementation with Streptococcus faecium M-74 on broiler body weight, feed conversion, carcass characteristics, and intestinal microbial colonization.

Two experiments were conducted to determine the influence of Streptococcus faecium M-74 supplementation of broiler diets. Mixed-sex or male only chicks were used in the experiments. Both experiments consisted of six dietary treatments and four replicates per treatment in a randomized block design. The S. faecium was fed alone for 21, 36, or 44 days or for 44 days with S. faecium supplemented in the water for the first 14 days. In another treatment, S. faecium was fed for 44 days, but the feed was restricted for Days 8 through 13. The S. faecium was also fed in combination with antibacterial products (AP) for 44 days. An additional diet was an unsupplemented basal, and another was supplemented only with AP. In Experiment 1, feed efficiency was significantly better with the basal and diets supplemented with S. faecium than with those diets supplemented with AP or AP and S. faecium. In Experiment 2, BW of broilers at 44 days of age were significantly heavier for broilers receiving S. faecium in the feed and also S. faecium in the water for the first 14 days as compared with broilers receiving AP or AP and S. faecium supplementation. There were no significant differences in carcass yield or composition characteristics. In Experiment 1, the scores representing S. faecium colonies found in the intestinal tract were not influenced by dietary treatment. The ceca had the highest S. faecium score of any of the intestinal tract locations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1990

The role of plasma thyroid hormones in the regulation of body weight of single comb White Leghorn and broiler embryos.

Studies were conducted to determine if sex differences in embryo weights existed in a light-weight breed of chickens (the Single Comb White Leghorn, SCWL) and in a heavy broiler strain of chickens. Plasma thyroid hormone concentration was measured to determine its relationship to embryo weight. Male SCWL embryos were heavier than females at 15 and 17 days of incubation, but not at 13 days. Male broiler embryos were heavier than females at 13 and 15 days of incubation, but not at 17 days. There was no sex difference in the levels of plasma triiodothyronine (T3) or of tetraiodothyronine (T4) of SCWL embryos at those respective ages. The plasma T4 in male broiler embryos was significantly lower than that in the females at 15 and 17 days of incubation, but not at 13 days. There was no relationship between plasma T3, and the weight of SCWL embryos. There were significant linear regressions of embryo weight on the plasma T4 levels for SCWL males at 13 and 15 days of incubation and for SCWL females at 13 and 17 days of incubation, respectively. A significant regression of embryo weight on plasma T4 was found in female broiler embryos at 13 days of age, but not in females at other ages or in males at any of the ages studied.

Age Factors↗

PubMed1990

The effects of energy and amino acid levels on performance and carcass quality of male and female broilers grown separately.

Studies were conducted to evaluate the response of male and female broiler chickens to diets containing different levels of energy and amino acids. Two energy series were compared: 3,080, 3,135, and 3,190 kcal of ME/kg ("low") and 3,190, 3,245, and 3,300 kcal of ME/kg ("high") in pelleted starter, grower, and finisher diets. Diets provided a minimum of 85, 90, 95, 100, 105, and 110% of suggested amino acid recommendations for the broiler male except for Met and TSAA, which were kept at 105%. Modifications were made in feeding periods, recognizing the differences in rate of gain and marketing ages of the two sexes. Feeding periods were 0 to 21, 21 to 42, and 42 to 56 days for males and 0 to 18, 18 to 35, and 35 to 49 days for females. Four floor pen trials utilizing 9,600 male and 9,600 female broilers were conducted. Birds were processed to determine dressing percentage and abdominal fat pad weights. Energy content of the diets had no significant (P greater than .05) effect on body weight or feed efficiency for male or female broilers. Carcass dressing percentage of females, but not males, was significantly (P less than .05) increased on the high energy series. Abdominal fat pad was not influenced by energy for either sex. For both sexes, increasing dietary amino acid levels resulted in significant (P less than or equal to .05) linear improvements in live weights and feed utilization and a reduction in abdominal fat pad weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗

PubMed1990

Influence of whey and probiotic-supplemented withdrawal feed on the retention of Salmonella intubated into market age broilers.

Broilers (6 wk of age) were crop-intubated with a nalidixic acid-resistant strain of Salmonella typhimurium and given four withdrawal feeds: 1) control feed (corn and soybean meal base, 18% CP and 3,200 kcal ME/kg); 2) control plus 5% whey (61% lactose); 3) control plus probiotic (6.8 x 10(6) cfu of Bifidobacterium pseudolongum, Bifidobacterium thermophilium, and Lactobacillus acidophilus); and 4) control plus 5% whey plus probiotic. In Experiment 1, male broilers received 9.8 x 10(7) cfu of S. typhimurium per bird midway through a 20-h fast. The withdrawal feeds were continuously offered through a subsequent period of 6 to 7 days. Live performance of broilers during this time was similar among treatments. Ceca from birds consuming whey were significantly (P less than .05) increased in weight and distended with gas. Recovery of S. typhimurium from the ceca was low with all treatments, and the effects of whey or probiotic at reducing the organism could not be determined. In Experiment 2, female broilers received the same four experimental feeds for 48 h. Salmonella typhimurium was intubated 24 h after feed access (1.2 x 10(7) cfu per bird). Again, no differences (P greater than .05) in performance occurred, but the inclusion of whey led to increased cecal weight and size (P less than .05). Large numbers of S. typhimurium were recovered from the ceca 24 h after intubation, but the levels were similar among treatments. Whey and probiotic in the withdrawal feed did not appear to affect the Salmonella level in ceca when the organism was consumed prior to marketing.

Animal Feed↗

PubMed1990

Oral rehydration therapy and broiler performance during summer growing conditions.

Two 8-wk broiler trials were conducted during summer growing conditions. Mild heat stress (30 C), as evidenced by panting, was induced by ventilation adjustments. From 4 to 8 wk of age, half of the pens were provided with a .10 strength, human oral rehydration therapy (ORT) solution containing .35 g sodium chloride, .25 g sodium bicarbonate, .15 g potassium chloride, and 4.0 g sucrose/L of drinking water. No significant (P less than .05) differences were found between treatments for 8-wk body weight. Mortality rate during the experiment period (4 to 8 wk) did not differ significantly between treatments in either trial, though it approached significance (P = .0558) in Trial 1 where mortality for broilers given ORT was 3.96% compared with 7.67% for control broilers. Feed efficiency was significantly (P less than .05) better in Trial 1 for ORT broilers, although no significant difference was found between treatments in Trial 2. Posttrial litter moisture measurements showed no significant differences (P greater than .05) between treatments in either trial. A crystalline deposit was observed in the internal filters of the bell-type waterers, which was probably caused by the sucrose (sugar) component of the ORT solution.

Animals↗

PubMed1991

Specific gravity of eggs and eggshell weight from commercial layers and broiler breeders in relation to time of oviposition.

Eggs were collected from 1 day of production of Hy-Line W36 commercial egg production hens 55 wk old. Also, eggs were collected from 1 day of production of Arbor Acres broiler breeder hens when they were 40 and 55 wk of age. The eggs were immediately weighed (EW) after collection and specific gravity (ESG) determined. The eggs were then broken and the contents removed. Shells were washed, air dried, and weighed. The weights of shells (ESW) were calculated using the following formulas: Broiler breeder ESW = 1.9128 x EW - 1.9741 EW/ESG and layer ESW = 1.9140 EW - 1.9754 EW/ESG. Shell density (ESD) was calculated using a modification of this formula. Egg weights of both commercial layers and broiler breeders were heaviest in the early morning. There was a steady decline in EW until 1545 h; EW increased thereafter. Specific gravity of eggs was highest in the morning, declined until 1245 h, and then increased thereafter. Shell weight was also highest in the morning, declined until 1245 h, and then increased thereafter. The calculated and measured ESW were highly correlated. The ESD was 2.147 and 2.160 for the commercial layers and broiler breeders, respectively.

Animals↗

PubMed1992

Influence of dietary taurine on performance and fat retention in broilers and turkey poults fed varying levels of fat.

Taurine, an amino acid synthesized from Met, primarily functions in bile acid conjugation. Four experiments were conducted to determine whether Tau supplementation of broiler cockerels and female turkey poults to 3 wk of age would influence performance and fat retention at different levels of dietary fat. In these experiments, Tau was added at 0 or .8% to a corn and soybean meal basal diet with dietary poultry fat added at 0, 5, or 10%. Taurine did not affect BW gain of broiler cockerels; however, in one experiment feed efficiency was improved (P less than .01) during the 1st wk and fat retention was improved (P less than .06) at 7 days of age. In experiments with turkey poults, dietary Tau did not affect weight gain but improved feed efficiency (P less than .01) during the 1st wk and decreased overall feed efficiency (P less than .01) in one experiment. Improvement of fat retention by Tau at 14 days was significant (P less than .02) in one experiment and approached significance (P less than .07) in the other experiment. Fat supplementation of both the broiler and turkey diets significantly (P less than .05) improved weight gain, feed efficiency, and fat retention. Supplementary Tau appears to have little effect on performance of broilers and turkeys.

Animal Feed↗

PubMed1993

Characterization of lipogenic and lipolytic activity, muscle tissue composition, and DNA and RNA levels of broilers eating ad libitum or severely restricted at an early age.

Four experiments were conducted to characterize the rates of lipogenic and lipolytic activities and the composition and DNA and RNA concentrations in muscle tissue of broilers that were feed restricted at an early age. In all experiments, feed restriction (40 kcal/day per bird) was initiated at 4 days of age with ad libitum consumption of feed resuming at either 11 (Experiments 1 and 2) or 10 (Experiments 3 and 4) days of age. Female chicks in Experiment 1 were feed restricted at the same level from 4 to 9 days of age. Birds consuming feed ad libitum served as controls in all experiments. Broilers restricted for 7 days had significantly lower plasma very low density plus low density lipoproteins (VLDL+LDL) than the ad libitum birds at 49 days of age in Experiments 1 and 2. However, the reverse was observed at 28 days of age, as plasma triglycerides and lipoproteins and lipogenesis were greater in restricted chicks when compared with controls. No significant differences were observed in plasma triglycerides at 49 days of age or lipolysis, DNA and RNA concentrations, muscle protein, and muscle fat at 28 days of age between restricted and ad libitum broilers. Results from these studies indicate that early feed restriction may have induced a metabolic shift in restricted broilers that increased lipogenesis at 28 days of age, followed by a partitioning of excess nutrients to support anabolic activity at market age.

Adipose Tissue↗

PubMed1993

Broiler chick and laying hen tolerance to sodium hypochlorite in drinking water.

Two broiler and two laying hen experiments were conducted to establish threshold levels for sodium hypochlorite use in poultry drinking water. Both broiler experiments were of 21-days duration, and the first and second hen experiments ran for 8 and 4 wk, respectively. A 5.25% sodium hypochlorite solution was used to provide chloride levels of 0, 10, 100, or 500 ppm in the first broiler study and 0, 150, 200, 250, 300, 350, 400, or 450 ppm in the second study. Comparable sodium levels from sodium bicarbonate were additional treatments in the first broiler experiment. The initial hen study had drinking water treatments of 0, 50, or 100 ppm chloride whereas in the second study, treatments varied from 0 to 70 ppm chloride at 10-ppm intervals. In chick experiments, water intake was reduced by 100 ppm chloride and body weight by 300 ppm. Hen experiments demonstrated the adverse effect level to be 40 ppm for water consumption and 60 ppm for egg production when the application was to pullets producing eggs at a high rate in warm weather. Water consumption of older hens in cooler weather was adversely affected by 50 ppm chloride, but egg production, egg weight, or daily feed intake was not reduced by 100 ppm.

Animals↗

PubMed1993

Research note: the performance of spring- and summer-reared broilers as affected by precision beak trimming at seven days of age.

In each of two duplicate trials approximately 2,500 day-old Peterson x Arbor Acres straight-run broiler chicks were equally divided between two treatments of three pens each. Treatment 1 was maintained as controls (C), and Treatment 2 birds were precision beak-trimmed (PBT) at 7 days of age. Feed and water were supplied for ad libitum consumption to both groups. Trials 1 and 2 were initiated in March and June, respectively. Performance of spring-reared broilers were comparable regardless of beak trimming procedure, except that PBT broilers experienced slightly higher mortality after PBT. Final body weights of the summer-reared broilers were 15% lower than those reared in the spring. Additionally, PBT resulted in significantly reduced final body weights and feed intake. There were no significant differences in mortality or feed conversion due to PBT.

Age Factors↗

PubMed1994

Effect of halofuginone on broiler skin strength when used in a shuttle anticoccidial program.

Continuous feeding of the anticoccidial halofuginone to broilers is associated with reduced skin tensile strength and increased skin tearing during processing. The possible mitigating effect of shuttle administration of halofuginone and salinomycin to female broilers was evaluated. Halofuginone or salinomycin were included in the starter and grower diets in all four possible combinations, with anticoccidial omitted from the finisher diets. Starter, grower, and finisher diets were fed to broilers through 3, 6, and 7 wk of age, respectively. Skin strength of pullets fed a diet based on milo and corn (NW) vs a diet based on corn was also compared in a factorial arrangement. Two further treatments were also included: 1) halofuginone-only NW diet supplemented with 2,500 ppm ascorbic acid from 0 to 7 wk; and 2) NW diet reared on wire floor without anticoccidial treatment. Skin tensile strength was determined at 3, 6, and 7 wk of age. Dietary composition had no effect upon skin strength or BW of broilers. Addition of ascorbic acid to the diet containing halofuginone anticoccidial did not improve skin strength. Continuous feeding of halofuginone reduced skin strength whereas withholding anticoccidial and continuous feeding of salinomycin resulted in high skin strength. When halofuginone was used in shuttle feeding programs with salinomycin, there were no differences in skin strength at 7 wk of age compared to birds that were continuously treated with salinomycin. These results suggest halofuginone may be used in a shuttle program either during the starter or grower phase without adverse affect on skin tensile strength at slaughter.

Animal Feed↗