Effects of functional oils on performance and carcass characteristics of broilers under two different temperature environments.

As antioxidants such as some functional oils are good candidates to mitigate heat stress, a commercial blend of functional oils (Essential, Oligo Basics USA LLC, Cary, NC; active ingredients: cashew nut shell oil and castor oil) was used to study the effects of two ambient temperatures (moderate and high) on broiler chicken performance and carcass parameters. A total of 2,240 straight-run one-day-old chickens were sorted by weight, randomized among 28 floor pens with 80 chickens per pen and 7 replicates for each treatment. Birds were assigned to one of 4 dietary treatments in a 2 × 2 factorial arrangement with two temperature environments (moderate and high) and without or with Essential supplementation (1.5 kg/ton). Variances for the average temperature, relative humidity, and dew point for the two environments were different (P < 0.001), showing that the high-temperature environment reached higher temperatures and dew points. Essential supplementation increased body weight gain at 42 D of age (2.548 vs. 2.508 kg; P < 0.01) and tended to improve feed conversion (1.621 vs. 1.644; P = 0.09) independent of temperature environment. The high-temperature environment increased mortality (7.5 vs. 12.4%; P = 0.03) and carcass yields (77.5 vs. 76.2%; P < 0.01). Breast yields were affected by an environment by Essential interaction (P < 0.01). Whereas the high-temperature environment decreased breast yield in control birds, it did not decrease breast yield in birds supplemented with Essential. Finally, breast yields were increased by Essential supplementation (23.6 vs. 22.9%; P < 0.01) regardless of the ambient temperature. In conclusion, Essential supplementation improved weight gains and carcass characteristics, and high-temperature environments decreased breast yields when Essential was not supplemented.

Evaluation of a new generation phytase on phytate phosphorus release for egg production and tibia strength in hens fed a corn-soybean meal diet.

To test the effect of several inclusion levels of Citrobacter braakii phytase (CBP), on phytate P release, 420 50-wk-old-Bovans White hens were randomly allocated to 7 treatments with 5 replicates of 12 hens each. The experimental period lasted 12 weeks, first 8 for adaptation and last 4 for data collection. Feed and water were provided ad libitum. Treatments were: (1) a 0.12% basal corn-soybean meal diet deficient only in non-phytate P. Treatments 2 and 3 were added with constant increases of 0.11% inorganic P, to get a linear hen response to P addition. Treatments 4 to 7 were the addition of 300; 600; 1,200; and 1,800 phytase units (FYT)/kg to the basal diet. Variables analyzed were hen productive performance (HPP) and tibia resistance to fracture (TRF), and mineral content. Data were analyzed as a Complete Randomized Design (CRD). The results from treatments 1 to 3 were analyzed by a regression model to test for a significant linear response (P < 0.05). Then for every level of CBP added (treatments 4 to 7), the linear regression equation was solved to find out the equivalent value of released P. Based on hen health and welfare, the response variables that yielded realistic P equivalence values for the CBP levels used in the present trial were the tibia data. Following the significant (P < 0.001) linear response, the equations; TRF, kg (Y = 28.16X + 17.42 R2 = 0.84); Tibia Ca, % (Y = 11.6X + 14.2 R2 = 0.80); Tibia P, % (Y = 11.6X + 6.1 R2 = 0.81); and T ash, % (Y = 33.3X + 38.1 R2 = 0.80). Under the experimental conditions of this trial, the HPP variables were not a sensitive parameter to measure P release; whereas, tibia parameters showed the following average P release values per level of CBP inclusion in the corn- soybean meal diet; 300 FYT/kg = 0.099%, 600 FYT/kg = 0.141%, 1,200 FYT/kg = 0.182%, and 1,800 FYT/kg = 0.198%.

Aflatoxins, hydroxylated metabolites, and aflatoxicol from breast muscle of laying hens.

Aflatoxins (AF) are toxic fungal secondary metabolites that are pathological to animals and humans. This study identified and quantified AF (AFB(1), AFB(2), AFG(1), AFG(2)) and their hydroxylated metabolites (AFM(1), AFM(2), AFP(1)) and aflatoxicol (AFL) from laying hen breast muscles. Aflatoxins pass from cereal feed to the laying hen tissues, causing economic losses, and from there to humans. To detect the passage of AF from feed to hen breast muscle tissues, an experiment that included 25 Hy-Line W36 121-wk-old hens was performed for 8 d. Hens in individual cages were distributed into 3 groups: a control group, with feed free of AFB(1), and 2 experimental groups, with feed spiked with 2 AFB(1) dosages: 30 µg·kg(-1) (low) or 500 µg·kg(-1) (high). The daily feed consumption per hen was recorded and afterward hens were euthanized and breast muscles were collected, weighed, and dried individually. Aflatoxins were extracted by 2 chemical methods and quantified by HPLC. Both methods were validated by lineality (calibration curves), recovery percentage (>80%), limit of detection, and limit of quantification. The AF (µg·kg(-1)) averages recovered in control breast muscles were as follows: AFB(1) (18); AFG(1), AFM(2), and AFL (0); AFG(2) (1.3); AFM(1) (52), and AFP1 (79). Hens fed with feed spiked with 30 µg·kg(-1) of AFB(1) had AFG(1) (16); AFG(2) (72); AFM(1) (0); AFM(2) (18); AFP(1) (145); and AFL (5 µg·kg(-1)). Hens with feed spiked with 500 µg·kg(-1) of AFB(1) had AFG(1) (512); AFG(2) (7); AFM(1) (4,775); AFM(2) (0); AFP(1) (661); and AFL (21 µg·kg(-1)). The best AF extraction method was Qian and Yang's method, modified by adding additional AF from both Supelclean LC18 SPE columns; its limit of detection (0.5 ng·mL(-1)) was lower compared with that of Koeltzow and Tanner, which was 1 ng·mL(-1).

Identification and quantification of aflatoxins and aflatoxicol from poultry feed and their recovery in poultry litter.

Aflatoxins (AF) are toxic fungal secondary metabolites and are known mycotoxins pathological to animals and humans. Poultry litter is frequently used as a food supplement for ruminants, and when poultry feed contains AF, the litter becomes contaminated as well, thus having an effect on livestock health. This study identified and quantified AF (AFB(1), AFB(2), AFG(1), and AFG(2)) from poultry feed and their recovery, together with their metabolites (AFM(1), AFM(2), AFP(1), and aflatoxicol) in litter. An experiment with 25 Hy-Line W-36 hens, in their second production stage, 121 wk old, was carried out. Hens were distributed in 3 groups placed in individual cages and 1 ration of 250 g of feed was given to each hen daily. Nine hens of the control group were fed with clean feed, without AFB(1); the other 2 experimental groups, with 8 hens each, were fed with 2 AFB(1) concentrations: 30 and 500 microg.kg(-1). The feed was replaced and weighed daily throughout a 7-d period to register the amount of feed consumed by the hens. Litter from each hen was collected, weighed, and dried individually. The chemical analysis of 40 g of each one of the 200 feed and 200 litter samples was chemically extracted and concentrated with immunoaffinity columns for total AF. To quantify AF, calibration curves for each AF were done by HPLC. Feed samples of the 3 groups presented significant difference with AFB(2) and AFG(2), whereas in litter samples, there were significant differences for AFG(2) in the 500 microg.kg(-1) group. Poultry litter had traces of AFM(1), AFM(2), AFP(1), and AFL with no significant differences among treatments. Aflatoxin B(1) prevalence in litter samples can cause damages in livestock because this mycotoxin reduces the digestibility of ruminant feed up to 67%.

Blood acid-base and plasma electrolyte values in healthy ostriches: the effect of age and sex.

The effect of age and sex on blood acid-base and plasma electrolyte values was determined in venous blood samples from 45 clinically healthy ostriches (Struthio camelus) from 26 days to 6 years of age. Animals were divided by age into four groups and the group of adults was divided by sex into two subgroups. Blood samples were collected without sedation. There was a significant (P<0.05) age difference in blood values of base excess (BE), plasma HCO(3)(-), total CO(2) (TCO(2)), Na(+), K(+), Cl(-) and anion gap (AG). The highest plasma concentrations of Na(+), Cl(-) and value of AG were found in adult ostriches with a steady decrease to chicks. A significant (P<0.05) sex difference in adult animals with higher blood pH, lower blood values of pCO(2), BE, plasma concentrations of HCO(3)(-), TCO(2) and K(+) was found in females. We concluded that blood acid-base values and plasma electrolyte concentrations in ostriches are affected by age and sex.

Biodetoxification of aflatoxin-contaminated chick feed.

Two studies were done to study detoxification of aflatoxin (AF)-contaminated chick feed with Nocardia corynebacteroides (NC). In the first study, pathogenicity of the bacteria was studied; in the second, the nutritional value of detoxified feed was evaluated. Commercial corn was divided into 2 sublots, one of which was contaminated with AF. Both lots were divided into 2 parts; the first was inoculated with NC. Four corn-soybean diets were prepared from the 4 corn lots. A completely randomized design was used with 2 x 2 factorial arrangement in which the factors were AF contaminated or not and NC inoculated or not. One hundred Ross 308 chicks (1-d-old, male) were used in 4 treatments with 5 repetitions and 5 chickens per cage. Bird weight and feed consumption were recorded weekly. Each week, 1 chick per treatment repetition was killed for histopathologic analysis of liver, kidney, bursa of Fabricius, pancreas, and small intestine (duodenum, jejunum, and ileum) and for analysis by scanning electron microscopy of the 3 sections of the intestine. At 21 d (the end of both experiments), 1 chick per treatment repetition was killed, and moisture, lipid content, and residual AF in liver were detected. Results at 3 wk did not show differences between treatments (P > 0.05) in any of the variables. In the second study, the same methodology was used except that greater levels of AF were used (800 and 1,200 mug of AFB1/kg of feed). Results showed differences (P < 0.05) in body weight, lipid content, and residual AF in liver. Histopathologic studies showed statistical differences in lesion severity in liver, duodenum, and kidney. Scanning electron microscopy analysis showed severe lesions of intestinal mucosa that mainly affected tight junctions in AF treatments. It can be concluded that NC is safe for chicks and may be used to partly detoxify chicken feed contaminated with AF.

Cholesterol and n-3 and n-6 fatty acid content in eggs from laying hens fed with red crab meal (Pleuroncodes planipes).

Red crab (Pleuroncodes planipes) is a marine crustacean that represents an abundant resource that has not been properly used. The aim of this study was to evaluate the effects on cholesterol and n-3 and n-6 FA content in eggs when red crab meal (RCM) was included in laying hen rations. Ninety White Leghorn laying hens were randomly distributed into 3 treatments: control (0%RCM), 3% red crab meal (3%RCM), and 6% red crab meal (6%RCM) for 3 wk. Cholesterol and linoleic (LA), alpha-linolenic (ALA), arachidonic (AA), eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids were analyzed by gas chromatography. Performance parameters and cholesterol content were not different among treatments (P > 0.05). Total lipids were different in the control group and 6%RCM (9.0 and 9.4% respectively) compared with 3%RCM (10.9%). With 3%RCM and 6%RCM, the levels of all fatty acids analyzed were higher than in the control. Diets with 3 and 6% RCM doubled the content of ALA (16.4 and 15.4 mg/100 g of egg, respectively). Eicosapentaenoic acid was lowest in 0%RCM (6 mg/100 g of egg) compared with 3%RCM (13 mg/100 g) and 6%RCM (17 mg/100 g). Similar results were obtained for DHA (56, 133, and 246 mg/100 g of egg). Linoleic acid and AA were highest (1,211 and 228 mg/100 g, respectively) with 3%RCM and with 6%RCM (1,151 and 200 mg/100 g, respectively) vs. control (890 and 163 mg/100 g). The ratio of n-6 to n-3 FA was 3 times lower with 6%RCM than in the control. It was concluded that inclusion of red crab meal in laying hen rations at levels of 3 and 6% (P < 0.05) increased the n-3 and n-6 fatty acids content in eggs.

Effects of Sunlight Illumination of Marigold Flower Meals on Egg Yolk Pigmentation.

The effect of sunlight illumination of marigold flower meal on the pigmentation of feed for laying hens and of their resulting egg yolks was evaluated by high-performance liquid chromatography and by subjective and light reflectance colorimetry techniques. Illumination did not have an effect on the identity of carotenoids in the flower meal. Interestingly, illuminated marigold flower meals yielded an oleoresin with a higher all-trans-zeaxanthin level, with respect to meals kept in darkness. A higher level of all-trans-zeaxanthin was also present in feed pigmented with that oleoresin. Additionally, this pigmented feed showed the best color values and resulted in egg yolks with good color; remarkably, these egg yolks had a low pigment content with respect to control treatments. Thus, sunlight illumination of marigold flower meal showed a positive effect on egg yolk color; the main factors contributing to this effect were not the identity or quantity of carotenoids in laying hen feed or egg yolks, but rather other as yet unidentified marigold component(s) which was (were) somehow influenced by sunlight illumination.

[Production of cassava whole meal (N. esculenta Crantz) to prepare a feed for growing chicks. II. Evaluation of cassava whole meal in growing chicks]. / Elaboración de una harina integral de yuca (N. esculenta Crantz) para alimentación de pollitos de engorde. II. Evaluación de una harina integral de yuca en pollitos de engorde.

About 50% of the raw materials used for poultry feeds are constituted of sorghum as a energy source. The purpose of this work was to evaluate the nutritional quality of a cassava whole meal (CWF: 61.2% and 38.8% of root and leaf flours, respectively) for growing chicks. The sorghum was partially substituted from a basal diet by 15, 30 and 45% of CWF. Four diets based of sorghum, soybean meal and CWF were formulated. Levels of 0.0, 8.6, 16.4 and 23.7% of CWF were included in the diets. White Vantress chicks (96) were used in the nutritional experiment during 28 days. Each treatment was assayed with 24 chicks. The diet containing 23.7% of CWF showed the lower weight gain and feed efficiency (p < 0.05) as compared with the other diets, and the liver/ bird weight relation increased directly with the increment of CWF.