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1.
1. Associations between body weight and rectal temperature were observed in female turkeys.

2. Turkeys with lower weights between 13 and 30 d of age tended to have higher temperatures.

3. Turkeys with lower weights at 7 d exhibited depressed body temperatures.

4. Higher or lower body temperatures may be associated with poorer performance depending on the time of appearance.  相似文献   


2.
Broiler chicks and turkey poults were divided at hatching into experimental and control groups. Experimental birds were fed a diet contaminated with 4 ppm ochratoxin A, whereas the ration of control birds was confirmed to be mycotoxin free. Birds were killed at fortnightly intervals up to 10 weeks old and skeletal changes were investigated. Almost all experimental birds developed generalised skeletal osteopenia with disturbed endochondral and intramembranous bone formation. Histological changes in diaphyseal cortices could account for the reduced breaking strength of bones from birds fed mycotoxin, which have been reported by others. One bird showed changes consistent with a diagnosis of hypophosphataemic rickets. In others, however, osteoid formation was defective and changes were interpreted as osteoporosis. Although it might be tempting to suggest that osteoporosis is a result of a direct toxic effect of ochratoxin on osteoblasts, the effect of inanition, inactivity and general debility may be equally important.  相似文献   

3.
Two-to-5-week-old turkey poults from three large Minnesota flocks exhibited ataxia, flaccid paralysis, and up to 5% mortality as unexpected death. The major post-mortem finding was cerebellar hemorrhage and softening detected in 22 of 89 clinically affected poults. Histologic findings were severe focal or multifocal poliomyelomalacia in the lumbosacral intumescentia of the spinal cord, cerebellar malacia, and single-cell or multifocal coagulative necrosis of pancreatic acinar cells. Thirty of 32 clinically affected poults examined had microscopic spinal cord lesions, 12 of 48 had cerebellar lesions, and 26 of 47 had pancreatic lesions. Gross and microscopic cerebellar lesions resembled those of vitamin E deficiency in chicks. Hepatic selenium levels were approximately twice normal expected levels for poults.  相似文献   

4.
5.
Corn-based diets contaminated with various concentrations of a moniliformin-producing isolate of Fusarium moniliforme var. subglutinans were found to be lethal for chicks, ducklings, and turkey poults. Ducklings appeared to be the most sensitive to the lethal effects of the toxic feed. Gross lesions were ascites, hydropericardium, and myocardial pallor. Microscopic lesions were limited to the heart and liver, and they consisted of degeneration and necrosis of the myocardium and degeneration of hepatocytes. Cardiotoxicosis was the apparent cause of death.  相似文献   

6.
Ten turkey poults each were placed in one of four groups: control, thyroxine (T4), furazolidone (FZ), and FZ + T4. Thyroxine (T4), at a concentration of 1 ppm, was included in the ration of poults fed T4 and FZ + T4, and furazolidone (FZ), at a concentration of 700 ppm, was included in the ration of poults fed FZ and FZ + T4 from 2 to 5 weeks of age. Levels of plasma T4 decreased significantly (P less than or equal to 0.05) between 2 and 5 weeks in control and FZ poults. At 5 weeks, plasma T4 levels were significantly (P less than or equal to 0.05) lower in FZ poults than in control poults and significantly (P less than or equal to 0.05) lower in the FZ + T4 poults than in the T4 poults. Exogenous administration of T4 had no effect on development of the round heart syndrome or on body weight, but significantly increased feed consumption in FZ-fed poults during weeks 4 (P less than or equal to 0.05) and 5 (P less than or equal to 0.01). Inclusion of T4 in the ration increased plasma levels of the hormone 12x in both T4 and FZ + T4 poults and significantly (P less than or equal to 0.05) increased myocardial glycogen content in T4 poults but not in FZ + T4 poults.  相似文献   

7.
1. An experiment was performed to elucidate the subsequent effects of high-non-phytate phosphorus (NPP) diets on growth performance, blood metabolites, bone characteristics and P retention of broilers fed on low-NPP grower diets. The 42-d study was designed as a 2 × 2 × 2 + 1 factorial, which included two starter NPP concentrations (4.5 and 5.5 g/kg; d 0–21), two grower NPP concentrations (1.5 and 2.3 g/kg; d 22–42), with or without phytase (1000 FTU/kg), with a reference diet containing an adequate NPP concentration over the course of the trial.

2. In the starter period, growth performance and P retention were not affected by experimental diets. The high-NPP diet increased plasma P concentration, increased tibia ash and tibia P contents and decreased plasma alkaline phosphatase (ALP) activity at d 21.

3. No significant interaction was observed between NPP concentrations in the starter and grower periods and phytase. The main effect data indicated that the increase in NPP concentration in the starter diets had no effects on growth performance in the grower period and overall. The high-NPP diet in the early stage of growth reduced plasma P concentration, plasma ALP activity and tibia ash content at d 42. The main effect data also showed that exogenous phytase increased body weight gain in the grower period and overall.

4. It can be concluded that feeding increased NPP diets have no effects on growth performance in the starter period. This feeding strategy results in negative effects on plasma P concentration and bone ash content at d 42. Also, exogenous phytase is effective in improving growth performance, bone characteristics and apparent P retention of growing broilers fed diets that are inadequate in phosphorus.  相似文献   


8.
Male turkey poults were fed on diets containing either adequate (29%) or inadequate (20%) amounts of crude protein from 1 d to 6 weeks of age. Each bird was weighed and the length of its lower‐leg measured at 1 d and at 6 weeks of age.

The initial body weight of adequately‐fed turkeys bore little or no relationship to 6‐week body weight. Length of lower‐leg at 1 d gave a more reliable prediction of body weight ranking at 6 weeks. In contrast initial body weight was more reliable than initial bone length in predicting body weight ranking at 6 weeks when the low‐protein diet was fed.  相似文献   


9.
1. Control by competitive exclusion of intestinal colonisation by Salmonella infantis was studied in domestic chicks and turkey poults given a commercial product developed for use with chickens, compared with two similar preparations containing intestinal microorganisms from turkeys. 2. Each type of material protected both avian species when given orally before challenge; the degree of protection depended at least as much on the type of preparation as its host origin.  相似文献   

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12.
The objective was to evaluate interactions between starter protein (180 vs. 200 g/kg, DM basis) and a mixture of essential oils (EOs; containing thymol, eugenol, vanillin, limonene and guaiacol) on growth, metabolic and ruminal functions of Holstein dairy calves. In a completely randomized 2 × 2 factorial design, 48 calves, 3 days old (averaging BW 42.7 ± 1.9 kg), were allocated into groups fed the following diets: (i) 180 g/kg CP with no EO (180P‐NEO); (ii) 180 g/kg CP with EO (180P‐EO); (iii) 200 g/kg CP with no EO (200P‐NEO); and (iv) 200 g/kg CP with EO (200P‐EO). The EO was supplemented as 1 g/kg of starter DM. Calves were fed ad libitum starter diet and were weaned at day 59 of age, but diets continued until day 80. There were no interactive effects of CP and EO on intake and growth. Pre‐weaning feed efficiency tended to be increased for 200P‐EO (p = .09). Average daily gain and feed efficiency during pre‐weaning period as well as weaning weight were increased (p < .05) by EO, whereas wither height was increased by EO (p = .03) and tended to be increased for 200P vs. 180P (p = .06). Post‐weaning blood urea nitrogen concentration tended to be lower in 180P vs. 200P (p = .08). Ruminal short‐chain fatty acids concentration was greatest in 200P‐EO. The EO increased both butyrate (p = .02) and propionate proportions (p = .01) and reduced acetate proportional ratio (p < .01). Ruminal ammonia‐N was tended to be lower in calves‐fed EO (p = .05) and was lower in those fed 180P vs. 200P (p < .01). In conclusion, supplementation of the starter diet with essential oil improved weight gain, growth and feed efficiency of dairy calves, irrespective of dietary protein content.  相似文献   

13.
1. Two experiments were performed to study the supplementation of valine, isoleucine, arginine and glycine (Val, Ile, Arg, Gly) in low-protein diets for broiler chickens in the starter (1–21 d; Exp. 1) and grower (22–42 d; Exp. 2) phases.

2. A low-crude protein (CP) diet was formulated to meet the requirements of all amino acids (AA) supplied by the control diet except for Val, Ile, Arg and Gly. The other experimental diets were obtained by the isolated or combined supplementation of the studied AA in the low-CP diet.

3. Growth, serum parameters and litter characteristics were taken in both of the experiments. Carcass measurements were taken in Experiment 2.

4. In the starter and grower phases, low-CP diets without supplementation resulted in birds with a poorer weight gain and feed conversion than those of the birds that received the control diet.

5. In the starter phase, individual supplementation with Val and Gly, but not Ile and Arg, restored the weight gain of the birds, while diets with the addition of Val + Gly, Val + Ile + Arg, Val + Ile + Gly and Val + Ile + Arg + Gly restored their feed conversion.

6. In the grower phase, weight gain was re-established at the same rate as the control diet for the diets supplemented with Val + Ile, Val + Ile + Arg, Val + Ile + Gly and Val + Ile + Arg + Gly. However, the feed conversion was restored only in birds that received the diet supplemented with all studied AA.

7. The supplementation of Val and Gly in low-CP diets was sufficient to avoid adverse effects in the performance and serum parameters of broilers in the starter phase. However, birds in the grower phase required the combined supplementation of Val, Ile, Arg and Gly, to prevent compromised performance.  相似文献   


14.
1. The efficacy of supplementation of a low-phosphorus (low-P) maize–soyabean meal diet for broiler chickens with two different microbial (fungal and bacterial) phytases was examined.

2. Broiler chickens received a low-P maize–soyabean meal diet containing either no phytase or one of the two phytases included at one and two times the manufacturer's recommended inclusion level for 21 d.

3. Titanium dioxide was included in the diets as an indigestible marker. Excreta were collected quantitatively from d 18 to 21, and at the end of the study the birds were killed and ileal digesta and leg bone samples collected.

4. No differences were observed for body weight gain and feed intake or apparent metabolisable energy (AME) among all dietary treatment groups.

5. Dietary phytase supplementation improved the apparent retention of Ca, Na and Cu and ileal phytate P absorption from 32% to 44% across inclusion levels.

6. Bone mineral density (BMD) was improved for both phytases across inclusion levels by, on average, 9% for the tibia and 13% for the femur.

7. Dietary phytase supplementation of the low-P diet improved apparent ileal digestibility of serine, glycine, valine, isoleucine, tyrosine, histidine, lysine and arginine.

8. When the results from the present study were combined with the results from other similar published studies and analysed statistically, factors such as dietary P and Ca concentration, as well as bird breed and age, rather than the type or activity of microbial phytase, had the greatest impact on the extent to which dietary supplementation improved P and Ca retention.

9. More work is required to explain the interrelationships between the multiple factors influencing the efficacy of phytase on the availability of dietary minerals.  相似文献   


15.
1. The effects of feeding T-2 toxin or diacetoxyscirpenol (DAS) at levels up to 1 ppm for 32 d on performance, health, small intestinal physiology and immune response to enteral and parenteral immunisation were examined in young poults. 2. Slight improvement in growth was observed in some groups of poults fed T-2 or DAS mycotoxins for 32 d, with no change in feed efficiency. Feeding both T-2 and DAS resulted in oral lesions which had maximal severity after 7-15 d. 3. Mild intestinal changes were observed at 32 d but no pathological or histopathological lesions were found. Both mycotoxins altered small intestinal morphology, especially in the jejunum where villi were shorter and thinner. In addition, both DAS and T-2 mycotoxins enhanced the proportion of proliferating cells both in the crypts and along the villi. Migration rates were reduced in the jejunum of poults fed T-2 toxin but did not change in the duodenum or in poults fed DAS. 4. No significant effects of T-2 or DAS were observed on antibody production to antigens administered by enteral or parenteral routes. 5. This study indicates that tricothecene toxins at concentrations of up to 1 ppm for more than 30 d influenced small intestinal morphology but did not affect growth or antibody production.  相似文献   

16.
Age-related changes in bone mineral density (BMD), cross-sectional area and strength strain index (SSI) of the long bones in the limbs and first lumbar vertebra of male Wistar rats were measured by a peripheral quantitative computed tomography (pQCT) method. One hundred and ten rats aged 2-30 months were used. The results indicate that the total (cortical + trabecular), cortical and trabecular BMD values of the metaphysis and cortical BMD values of the diaphysis in the long bones varied for each bone and differed from those of the first lumbar vertebra. The total BMD of long bones showed high values at 6-21 months and then decreased, but these did not always coincide with cortical and trabecular BMD. The values of SSI in the long bones varied. The values of total and cortical BMD and SSI of lumbar vertebra increased for 6-12 months and then decreased, but the trabecular BMD increased after 12 months. The total area in both the long bones and the first lumbar vertebra increased with the decrease in cortical area and the increase in the trabecular area with increasing age. It was concluded that age-related changes in bones, similar to those observed in humans, could be observed in some bones and parameters, although the age in rats when the so-called peak bone mass appears in the whole skeleton could not be clearly determined.  相似文献   

17.
1. A 2 × 3 factorial arrangement of treatments was used to investigate the effects of dietary calcium (Ca), phosphorus (P), and supplemental boron (B) (0, 75, and 150 mg/kg) on the performance, egg quality, bone strength, and mineral constituents in bone, serum and faeces.

2. A reduction by 18% in the dietary Ca-P concentration from the recommended levels for the hen strain reduced (P < 0.01) faecal excretion of ash, Ca and P concentrations, and shear force with stress of the tibia in association with decreased feed intake, whereas improved albumen height and Haugh unit values in the egg.

3. Supplemental B significantly decreased the feed consumption, egg weight and final body weight in hens, as well as the albumen height, but had no effect on either the biomechanical characteristics of bones or the mineral profile of the bones and serum. However, there was a significant increase in the egg production rate and a reduction in the damaged and shell-less egg ratio, and in the feed conversion rate in hens fed adequate Ca-P with 150 mg/kg B compared to those of the unsupplemented controls.

4. The amount of B that accumulated in the bones and serum was correlated with the amount of B consumed. B increased the faecal excretion of ash, Ca and B. In general, dietary variables had no effect on mineral composition of serum and tibia.

5. The magnitude of the response to dietary B was much more pronounced in hens fed a diet deficient in Ca-P with 75 mg/kg B; these hens exhibited a production performance and an egg quality comparable to those given adequate Ca-P with no added B.

6. The data presented in this study describing the measured bone properties did not corroborate the hypothesis that B is a trace element playing an important role in mineral metabolism and bone strength through an interaction with Ca, P and Mg.  相似文献   


18.
A 28-d experiment was conducted using 126 crossbred barrows to evaluate the addition of a genetically engineered Escherichia coli phytase to diets that were 0.15% deficient in available P. Growth performance, bone strength, ash weight, and the apparent absorption of P, Ca, Mg, N, energy, DM, Zn, Fe, and Cu were the response criteria. The pigs (2 pigs/pen) averaged 7.61 kg of BW and 30 d of age initially. The low-P basal diet was supplemented with 0, 100, 500, 2,500, or 12,500 units (U) of E. coli phytase/kg of diet, or 500 U of Peniophora lycii phytase/kg of diet. The positive control (PC) diet was adequate in available P. Pigs were fed the diets in meal form. Fecal samples were collected from each pig from d 22 to 27 of the experiment. There were linear and quadratic increases (P < 0.001) in 28-d growth performance (ADFI, ADG, and G:F), bone breaking strength and ash weight, and the apparent absorption (g/d and %) of P, Ca, and Mg (P < or = 0.01 for quadratic) with increasing concentrations of E. coli phytase. Pigs fed the low-P diets containing 2,500 or 12,500 U/kg of E. coli phytase had greater (P < or = 0.01 or P < 0.001, respectively) values for growth performance, bone breaking strength and ash weight, and the apparent absorption (g/d and %) of P, Ca, and Mg than pigs fed the PC diet. The addition of E. coli phytase did not increase the apparent percentage absorption of N, GE, DM, Zn, Fe, or Cu. There were no differences in the efficacy of the E. coli or P. lycii phytase enzymes at 500 U/kg of low-P diet for any criterion measured. In conclusion, there were linear increases in growth performance, bone breaking strength and ash weight, and the apparent absorption of P, Ca, and Mg with increasing addition of E. coli phytase up to 12,500 U/kg of diet. Also, all of these criteria were greater for pigs fed the low-P diets containing 2,500 or 12,500 U of E. coli phytase/kg than for pigs fed the PC diet. The addition of 500, 2,500, or 12,500 U of E. coli phytase/kg of low-P diet reduced P excretion (g/d) in manure by 35, 42, and 61%, respectively, compared with pigs fed the PC diet.  相似文献   

19.
Concurrent in vivo and in vitro studies were conducted to evaluate urea (U), soybean meal (SBM), ground soybeans (RAW), extruded soybeans (ES) or extruded soybeans plus urea (ES + U) as primary supplemental N sources in starter diets for Holstein steers. Three groups of 48 Holstein steers each were fed five different starter diets to 181 kg BW in three experimental periods over 2 yr. Average daily gains were similar (P greater than .05) for steers fed ES + U (1.12 kg), ES (1.08 kg) and SBM (1.09 kg) but lower (P less than .05) for those fed U (1.00 kg) or RAW (.97 kg) diets. Feed/gain was similar (P greater than .05) for ES-fed steers vs those fed other diets except U. From 181 to 477 kg, all steers were fed the same diet. Steers fed the RAW starter diet had the lowest (P less than .05) ADG for the entire period. The starter diets were used as substrates for ruminal microbial metabolism in eight dual-flow continuous culture fermenters. True OM digestion was higher and NDF and ADF digestion was lower (P less than .05) for the ES + U diet than for the ES diet. Dietary protein degradation was lowest (P less than .05) for the ES diet (64.4%). Total bacterial N flow was higher (P less than .05) with the ES + U, SBM and U diets than with the ES diet. Lysine flow was higher (P less than .05) for the ES + U diet than for all other diets except ES. Results of these experiments indicate that ES as a protected ruminal escape N source with or without added urea did not improve steer performance above that obtained from SBM in starter diets.  相似文献   

20.
Three trials, utilizing a total of 240 crossbred gilts, were conducted to study the influence of 0 (NB) or 220 (SB) microgram supplemental biotin/kg of diet on feedlot performance, plasma biotin and development of toe lesions in developing gilts. Corn-soybean meal diets were fed from weaning to 92 kg body weight. Gilts were housed on expanded-metal floors to 50 kg body weight and on partially slatted concrete floors until completion of the trials. Feedlot performance, hair and structural soundness scores were not different (P greater than .10) between NB and SB gilts. Plasma biotin (PB) levels were elevated (P less than .01) when supplemental biotin was included in the diet. Gilts consuming SB diets had fewer (P less than .01) toe lesions/gilt and lower (P less than .01) toe lesion severity scores/gilt compared with gilts fed NB diets. Heel-horn erosion and heel cracks were the most frequent toe lesions observed. Fewer gilts (P less than .01) developed side-wall toe cracks when fed SB diets. Supplemental biotin reduced the frequency of individual toes containing heel-horn erosion (P less than .10), heel cracks (P less than .05) and side-wall toe cracks (P less than .05) with the severity of these lesions not affected (P greater than .10) by supplemental biotin. These results suggest that biotin levels in corn-soybean meal diets are adequate for feedlot performance, and that supplemental biotin can improve hoof integrity, but will not prevent toe lesions.  相似文献   

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