Dietary contribution of iron from limestone and dicalcium phosphate for broiler chickens.

Iron is routinely supplemented in broiler feeds aiming to prevent dietary deficiencies. Limestone and phosphates are very rich in Fe; however, its contribution from these sources have not been thoroughly investigated with chickens. The present research was conducted to evaluate live performance and blood parameters of broilers when using limestone and dicalcium phosphate as sources of Fe. A total of 576 one-day-old male Cobb x Cobb 500 were allocated into a total of 72 battery cages, 6 treatments with 12 replication cages of 8 chicks at placement. Chicks were fed diets formulated with corn, soybean meal (SBM) with laboratory grade calcium carbonate and phosphoric acid (having traces of Fe). All chicks were fed a common prestarter without Fe supplementation (analyzed total 58.2 ± 2.4 mg/kg Fe) from placement to 7 d. Allocation of birds to dietary treatments was completely randomized on day 8. Treatments had increasing Fe derived from commercial limestone and dicalcium phosphate (analyzed Fe 7,218 and 4,783 mg/kg, respectively) progressively replacing calcium carbonate and phosphoric acid to provide graded increases in total Fe (analyzed Fe in the feeds were 57.6 ± 2.1, 92.0 ± 2.3, 124.1 ± 2.7, 159.3 ± 3.1, 187.2 ± 3.2, 223.7 ± 3.6 mg/kg, respectively). There were no effects of dietary Fe on live performance, hematocrit, and hemoglobin the end of the study on day 28 (P > 0.05). Increasing dietary Fe from commercial limestone and dicalcium phosphate led to a linear reduction in the percent ileal digestible Fe. However, linear increments in Fe retention, serum ferritin and liver Fe occurred when compared to feeds without Fe derived from limestone and phosphate dicalcium. It is concluded that Fe from limestone and dicalcium phosphate can be partially utilized by broiler chickens. It was estimated that the Fe retained from limestone and dicalcium phosphate is of 1.9%. Broilers fed corn-soy feeds (58.2 mg/kg Fe) do not require supplemental Fe.

PERSPECTIVE: Pollen Cryopreservation for Plant Breeding and Genetic Resources Conservation.

Pollen conservation is an important tool for the maintenance of plant genetic resources and can promote improved efficiency in breeding programs and germplasm conservation and exchange. This review aims to understand the importance of pollen cryopreservation and how to use it for distinct species in order to encourage the use of this methodology in germplasm banks and plant breeding programs. Pollen from many plant species have already been successfully cryopreserved in liquid nitrogen. Analogous with other plant structures, to maintain pollen viability after storage at ultra-low temperatures it is necessary to adjust the water content so that at least the freezable is removed. Optimum pollen moisture levels for cryopreservation varies among species and different methods have been applied to control moisture content. Common methods to decrease pollen moisture content include exposure to saturated solutions of various salts (which have a well-defined relative humidity), silica gel, dry air or treatment with vitrification solutions. It is our understanding that pollen cryopreservation is a safe and practical alternative for conserving genetic material that is often neglected by potential users. The technique has the potential to overcome challenges of breeding programs, such as flowering asynchrony between different parent genotypes, and the production of insufficient pollen in nature. Generally, pollen cryopreservation techniques tend to be simple enough to be used routinely in research, plant breeding and germplasm conservation programs.

Utilization of corn-based diets supplemented with an exogenous α-amylase for broilers.

A study was conducted to evaluate the effects of a supplemental α-amylase on energy and nutrient utilization of broiler chickens fed diets with variable amounts of corn. A total of 480 slow feathering Cobb × Cobb 500 male broilers were randomly distributed into 10 treatments with 8 replicates of 6 birds each. Birds were fed a common starter to 14 D post-hatch. The experimental diets were provided subsequently until 25 D, which were a conventional corn-soy basal diet (CS) and a corn-soy diet displaced with 40% of corn (CN). These were fed as-is or supplemented with 40, 80, 120, or 160 kilo-Novo α-amylase units (KNU)/kg. Dietary treatments were distributed factorially as a 2 × 5 arrangement (diet type vs. amylase). Samples of feed, excreta, and ileal digesta were analyzed for determination of ileal digestible energy (IDE), ME, total tract retention, and digestibility of dry matter, protein, and fat. No interactions between diet type and amylase were observed. The CN diet had lower (P < 0.05) energy utilization and nutrient digestibility when compared to the CS diet. AMEn and IDE increased (P < 0.05) by 110 and 207 kcal/kg, respectively, when CS and CN diets were supplemented with 80 KNU/kg. The amylase added to the CS diet led to quadratic increases (P < 0.05) on growth performance, IDE, AME, and AMEn, as well as in dry matter, protein, and fat digestibility. Energy utilization and crude protein digestibility were linearly increased (P < 0.05) when amylase was added to the CN diet or the extrapolated 100% of corn. In conclusion, energy utilization, digestibility of crude protein, fat, and dry matter increased with amylase supplementation in corn-soy-based diets. When amylase was tested in a complete diet having 53.6% corn, 100 and 105 KNU/kg maximized AMEn and IDE, respectively; however, the maximum energy response in the CN diet or 100% of corn was not achieved until 160 KNU/kg, suggesting an association between amylase dose optimization and dietary starch concentration.

New hybrids from peanut (Arachis hypogaea L.) and synthetic amphidiploid crosses show promise in increasing pest and disease tolerance.

The primary gene pool of the cultivated peanut (Arachis hypogaea L., allotetraploid AABB) is very narrow for some important characteristics, such as resistance to pests and diseases. However, the Arachis wild diploid species, particularly those from the section Arachis, still have these characteristics. To improve peanut crops, genes from the wild species can be introgressed by backcrossing the hybrids with A. hypogaea. When diploid species whose genomes are similar to those of the cultivated peanut are crossed, sterile hybrids result. Artificially doubling the number of chromosomes of these hybrids results in fertile synthetic polyploids. The objectives of this study were: 1) to obtain progenies by crossing amphidiploids with the cultivated peanut, and 2) to characterize these two groups of materials (amphidiploids and progenies) so that they may be efficiently conserved and used. Using morphological, molecular, and pollen viability descriptors we evaluated one cultivar of A. hypogaea (IAC 503), eight synthetic amphidiploids, and the progenies resulting from four distinct combinations of crossing between IAC 503 and four amphidiploids.

Digestibility marker and ileal amino acid digestibility in phytase-supplemented soybean or canola meals for growing pigs.

Two experiments using soybean meal (SBM) or canola meal (CM) were conducted to investigate whether the choice of digestibility marker influenced the apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of N and AA in diets supplemented with phytase. In each experiment, 18 barrows fitted with T-cannulas at the ileocecal junction were assigned to 3 diets consisting of a N-free diet to determine endogenous losses of N and AA, a semipurified diet (SBM in Exp. 1 or CM in Exp. 2), and the semipurified diet supplemented with phytase at 1,000 phytase units/kg. Three digestibility markers including acid-insoluble ash (AIA), chromic oxide (Cr2O3), and titanium dioxide (TiO2) were added to each diet at 3 g/kg. Each diet was fed for 7 d, consisting of a 5-d adjustment and a 2-d collection of ileal digesta. In both studies, basal ileal endogenous losses determined with Cr2O3 as a digestibility marker were lower (P<0.01) than with those determined with AIA or TiO2 digestibility markers. Using SBM as the protein source in Exp. 1, there was no interaction between phytase and digestibility marker on AID or SID of AA. The AID of N and AA in SBM using AIA as a digestibility marker tended to be lower (P<0.1) compared with Cr2O3 or TiO2 digestibility markers. Phytase supplementation increased (P<0.001) the AID of Ca and P. The use of AIA or Cr2O3 digestibility marker tended to be associated with lower (P<0.1) SID values compared with TiO2. Phytase did not affect the SID of N or any AA in SBM except for Met, for which there was an increase (P<0.05) with phytase supplementation. Using CM as the protein source in Exp. 2, there were significant interactions between digestibility marker and phytase. Phytase supplementation had effects (P<0.01) on AID or SID when Cr2O3 or TiO2 was used as the digestibility marker. With Cr2O3 or TiO2 as the digestibility marker in the CM diets, phytase supplementation increased (P<0.05) the SID of N and all AA (except Trp). There was no SID of N or AA response to phytase supplementation of CM when AIA was used as a digestibility marker. In contrast, there were no clear improvements in AA digestibility from phytase supplementation for SBM. Phytase effects on AID or SID of AA were dependent on the digestibility marker used in diets when CM was used as the protein source but not when SBM was used as the protein source. Therefore, AA digestibility response to phytase supplementation may depend on the protein being evaluated as well as the choice of digestibility marker.

Development of bone in chick embryos from Cobb 500 breeder hens fed diets supplemented with zinc, manganese, and copper from inorganic and amino acid-complexed sources.

Sources of Zn, Mn, and Cu (IZMC) as sulfates or as amino acid complexes (OZMC) were used to supplement Cobb 500 breeder hen diets. Experimental treatments consisted of diets supplemented with 1) 100, 100, and 10 mg/kg of Zn, Mn, and Cu, respectively, from IZMC (control); 2) 60, 60, and 3 mg/kg of Zn, Mn, and Cu, respectively, from IZMC plus 40, 40, and 7 mg/kg of Zn, Mn, and Cu, respectively, from OZMC (ISO); and 3) a diet with 100, 100, and 10 mg/kg of Zn, Mn, and Cu, respectively, from IZMC as in control plus 40, 40, and 7 mg/kg of supplemental Zn, Mn, and Cu from OZMC (on top). Ten replications of 20 females and 2 males were used per treatment. Eggs from breeders at 30, 40, 50 and 60 wk of age were incubated, and 5 embryos per replicate were collected at 10 (E10), 14 (E14), and 18 (E18) d of incubation. Midshaft width and calcification were measured for left tibia and femur stained with Alcian Blue and Alizarin Red S. At hatch, the left tibia of 5 chicks per replicate was sampled for histological evaluation of the diaphysis and distal epiphysis. Feeding the ISO treatment compared with the control diet increased the Zn (P < 0.05) but not Mn and Cu content of the yolk and albumen blend. At E14, the ISO and on-top treatments had a trend to increase tibia calcification at the rates of 1.6 and 1%, respectively (P < 0.1). The E18 ISO and on-top treatments had 2% thicker tibia compared with the control, regardless of hen age (P < 0.05). Also, at E18, calcification of tibia and femur was higher from hens fed the on-top treatment (P < 0.05). The chicks from the ISO and on-top groups had increased tibia moment of inertia (P < 0.01) at day of hatch. Broiler breeder hens consuming OZMC associated with IZMC produced embryos and hatching chicks with improvements in selected bone mineralization parameters.

Domiciliary treatment of febrile episodes in cancer patients: a prospective randomized trial comparing oral versus parenteral empirical antibiotic treatment.

Hospitalization and empirical broad-spectrum, intravenous antibiotics are the standard treatment for febrile cancer patients. Recent evidence supports the suggestion that febrile episodes in a low-risk population can be managed successfully in an outpatient setting, but the optimal drug regimen is unknown. In a prospective randomized clinical trial we compared ciprofloxacin 750 mg p.o. twice a day with ceftriaxone 2 g i.v. as a single daily dose for the empiric domiciliary treatment of febrile episodes in low-risk neutropenic and nonneutropenic cancer patients. A total of 173 patients, accounting for 183 febrile episodes, were enrolled in the study. Overall, successful outcomes were recorded for 76 of 93 (82%) febrile episodes in patients who were randomized to the oral regimen and for 68 of 90 (75%) febrile episodes in patients randomized to the i.v. regimen: this difference was not statistically significant. The success rate was similar in all subgroups of patients: neutropenic and nonneutropenic, with documented infection and with fever of unknown origin. There were 3 deaths in the group of patients treated with the parenteral regimen, and two of these were related to treatment failure. Both treatments were well tolerated, and the cost of the oral regimen was lower. This prospective study suggests that domiciliary antibiotic empiric monotherapy is feasible in febrile nonneutropenic or low-risk neutropenic outpatients in whom a bacterial infection is suspected, and that either an oral or a parenteral regimen can be used. A number of factors may influence the choice between an orally and an i.v.-administered antibiotic, but owing to the easier administration and lower cost, the oral regimen seems to be preferable.

Diet and risk of breast cancer: major findings from an Italian case-control study.

A large case-control study (2,569 women with breast cancer and 2,588 control women) carried out in Italy between 1991 and 1994 permits elucidation of breast cancer risk in relation to dietary patterns in a southern European population. Major findings include direct associations with the intake of bread and cereal dishes, sugar, and pork meat, and inverse associations with the intake of vegetable oils, raw vegetables, fish, beta-carotene, vitamin E, and calcium.

Meal frequency and coffee intake in colon cancer.

Several studies suggested that frequent eating may increase colon cancer risk. To further clarify this issue, a case-control study was carried out in six areas of Italy on 1,225 incident cases < 75 years of age with histologically confirmed colon cancer and 4,154 control subjects. The controls were hospitalized for acute, nonneoplastic conditions unrelated to long-term dietary modifications. After allowance for education, physical activity, intake of vegetables, and major energy sources, there was a trend of increasing risk with increasing eating frequency (odds ratio for > or = 4 vs. < or = 2 daily meals = 1.24). Coffee intake, which was inversely associated with cancer risk, exerted a modification effect, with an odds ratio of 1.89 for frequent eaters who drank fewer than two cups of coffee per day. Frequent eating increases, whereas high coffee intake decreases, the excretion of bile acids, which are suspected to be carcinogenic to the colon. Thus, it is conceivable that frequent coffee intake may counterbalance the effect of frequent eating.

Coffee consumption and the risk of breast cancer.

On the basis of clinical observations that some women with fibrocystic breast disease experienced resolution of the disease on eliminating methylxanthines from their diet, it has been suggested that coffee intake might be related to breast carcinogenesis. The relationship between coffee (mostly expresso and mocha), decaffeinated coffee and tea intake and breast cancer risk was therefore considered, combining data from two case-control studies, conducted in Italy between 1983 and 1994. Cases were 5,984 women, below age 75, with histologically confirmed breast cancer, and controls were 5,504 women admitted to hospital for a wide spectrum of acute, non-neoplastic, non-hormone-related diseases. The odds ratios (ORs) were estimated from multiple logistic regression equations including terms for study/centre, age, education, body mass index, smoking status, total alcohol intake, age at menarche and menopause, parity and age at first birth, use of oral contraceptives, use of hormone replacement therapy, history of benign breast disease and family history of breast cancer. No relationship was observed between coffee intake and the risk of breast cancer. The multivariate ORs were 1.17 (1.03-1.33), 1.17 (1.04-1.33), 1.21 (1.06-1.37) and 0.96 (0.83-1.11) for women drinking < 2, 2, > 2 to < 4 and > or = 4 cups/day compared to non-drinkers. Decaffeinated coffee was consumed only by 6-7% of cases and controls and the corresponding OR was 0.84 (0.72-0.98). Tea consumption was also low and not associated with the risk of breast cancer (OR 0.94, 95% CI 0.85-1.03). No significant heterogeneity was found for coffee intake across strata of age at diagnosis, education, body mass index, smoking status, total alcohol intake, age at menarche and menopause, parity, age at first birth, ever use of oral contraceptives, hormone replacement therapy, history of benign breast disease and family history of breast cancer. Thus, this study, based on a large data set, allows us to exclude the hypothesis that coffee intake is related to breast cancer risk in this Italian population.

Monounsaturated and other types of fat, and the risk of breast cancer.

We considered the role of monounsaturated and other types of fats on breast carcinogenesis, using data from a case-control study of 2,569 incident, histologically confirmed cases of breast cancer and 2,588 controls from six Italian areas. The multivariate odds ratios, adjusted for age, education, parity, menopausal status plus various sources of energy and types of fats, were 1.10 (95% confidence interval 0.99-1.23) for an increase of 10 g/day of saturated fat intake, 0.99 (0.94-1.04) for an increase of 10 g/day of monounsaturated fats, and 0.91 (0.87-0.96) for an increase of 5 g/day of polyunsaturated fats. The present data confirm that saturated, but not mono- or polyunsaturated fats, are directly, though moderately, related to breast cancer risk.

The new fluorinated quinolones for antimicrobial prophylaxis in neutropenic cancer patients.

Fluoroquinolones are the most attractive agents for prophylactic use in neutropenic cancer patients, due to their broad antimicrobial spectrum, high concentration in the faeces, systemic bactericidal activity, uncommon emergence of resistant strains and good tolerability. They have proved to be more effective than placebo, oral non-absorbable antibiotics or cotrimoxazole in the prevention of Gram-negative infections. In a prospective, randomised multicentre study performed by the GIMEMA infection program, ciprofloxacin was demonstrated to be more effective than norfloxacin for the reduction of febrile episodes, use of systemic antibiotics, and Gram-negative infections in neutropenic patients with haematological malignancies. The greater efficacy may be related to its better systemic or greater antibacterial activity. The potential problems related to the prophylactic use of fluoroquinolones are the increasing prevalence of Gram-positive infections caused by streptococci and coagulase-negative staphylococci; the reported emergence and nosocomial spread of resistant strains, especially among coagulase-negative staphylococci; the lack of their usefulness as empirical therapy in febrile neutropenic patients. Fluoroquinolones are today the better choice for preventing Gram-negative infections in neutropenic patients and ciprofloxacin should probably be preferred. More information on their efficacy and their relationship to the overall susceptibility of micro-organisms in patients with cancer would be valuable, and careful monitoring of patients treated with these drugs is therefore warranted.

Using teicoplanin for empiric therapy of febrile neutropenic patients with haematological malignancies.

The cumulative experience with teicoplanin in treating febrile neutropenic patients included in three different comparative clinical trials conducted at a single institution during a 3-year period, is presented. 152 febrile episodes in 129 neutropenic patients were treated with i.v. teicoplanin (6 mg/kg/d) combined with amikacin (15 mg/kg/d) plus ceftazidime (90 mg/kg/d). The study population comprised 75 patients with acute leukaemia and 77 marrow recipients: 53% (81/152) had a central venous catheter in place and 68% (103/152) had severe neutropenia (less than 100/mm3) at the beginning of the febrile episode. The overall response rate of the evaluable febrile episodes was excellent: 88% (107/122) improved. Bacteraemias due to Gram-positive cocci accounted for 75% of the total (42/56) and pathogens in the blood isolates were mostly staphylococci (coagulase-negative 14, coagulase-positive 13) and streptococci (13). The response rate of Gram-positive bacteraemias was good: 88% (37/42) improved and 75% (9/12) of Gram-positive bacteraemias having teicoplanin as the only antibiotic with in vitro activity against the infective strains were cured. Death due to infection accounted for 7% of total febrile episodes (11/152). Side effects were documented in 14% of the episodes. In a setting of high prevalence of Gram-positive infections caused by strains with a high rate of resistance to aminoglycoside and beta-lactam antibiotics, there may be an advantage in including teicoplanin in the initial empiric antibiotic regimen for febrile neutropenic cancer patients.

A pilot study of metoclopramide, dexamethasone, diphenhydramine and acupuncture in women treated with cisplatin.

A total of 26 women who submitted to cisplatin chemotherapy received as antiemetic treatment a combination of metoclopramide, dexamethasone and diphenhydramine. Acupuncture according to traditional Chinese medicine was also carried out. The results were compared with those obtained in a similar group of women with cancer, who were treated in the same setting with the same antiemetic combination but without additional acupuncture. Acupuncture was shown to increase complete protection from nausea and to decrease the intensity and duration of nausea and vomiting. However, the difficulties of performing acupuncture routinely in daily practice are a hindrance to its wider use.

Pharmacokinetics of vincristine in cancer patients treated with nifedipine.

The pharmacokinetics of vincristine (VCR) after an intravenous bolus dose of 2 mg were studied in patients with cancer with and without a concomitant treatment with the calcium-entry blocker nifedipine (NIF). VCR concentrations were determined by a sensitive radioimmunoassay. Pharmacokinetic data were analyzed by a nonlinear weighted least-square regression program (SAS-NLIN). A tri-exponential model fitted the raw data better than a bi-exponential model in five of 14 (35%) patients treated with VCR alone and in seven of 12 (58%) patients treated with VCR plus NIF (P = NS). The T1/2 alpha was shorter in NIF-treated patients, whereas the T1/2 gamma was longer in the NIF-treated group. The NIF-treated group showed an increase in the AUC O-infinity and AUC 1 to 96 hours, and a decrease in the AUC 0 to 1 hour. Total plasma clearance of VCR and 7-day urinary excretion of VCR was reduced in the NIF-treated patients. These data suggest that, when VCR is administered to NIF-treated patients with cancer, there is a decrease in VCR clearance from the body. Theoretically, a greater cytotoxicity may be anticipated.

Overdrive and programmed atrial electrostimulation in the study of the electrogenetic mechanism of atrial flutter in man.

The response of atrial flutter (AF) to programmed atrial stimulation (PAS) (13 cases) and overdrive atrial pacing (OAP) ws studied in a total of 18 patients. During PAS the return cycle was equal to the basic cycle of AF in six patients, shorter in one patient, and slightly longer in six; it was never compensatory. ATrial flutter terminated in two patients by PAS and by OAP in three. In 4 patients, PAS resulted in an acceleration of the AF rate, followed by spontaneous interruption within 2 seconds. In the remaining patients, the stimulation either converted the AF into an uncommon type of AF (two patients) or into atrial fibrillation that was followed by spontaneous return to sinus rhythm. In two patients it was possible to reproduce the AF with PAS; in one of the patients another type of AF was induced. Some of the data observed suggest a re-entry circuit as the electrogenetic mechanism responsible for AF in man.