Industrial egg residue as a calcium source in broiler feed: digestibility and growth performance.

Industrial egg residue (IER) possesses substantial concentrations of calcium and crude protein. The objective of this study was to measure the digestibility and performance of broilers when IER was added to the feed. Four treatments were tested, which caused increasing replacement of calcitic limestone by IER (0, 35, 70 and 100%) during a 42-day production cycle. First, total bird excreta were collected from broilers with and without IER, and we determined dry matter digestibility, apparent metabolizable energy (AME), calcium, and nitrogen retention. The IER presented 7.5% of crude protein, 31% of calcium, 209 kcal/kg of AME and the digestibility coefficients for dry matter, crude protein, and calcium were calculated at 83.95%, 86.20%, and 67%, respectively. After the digestibility test, the effects of IER on performance, carcass and meat yield were evaluated. No significant differences between the treatments were found in terms of performance (weight gain, feed conversion, consumption, and mortality), and no differences were found in terms of carcass or meat yield. A linear decrease in the percentage of abdominal fat was observed with increasing inclusion of IER in feed. These findings suggest that IER can totally replace limestone (calcium carbonate) in broiler diets.

Inclusion of industrial egg residue in the feed of laying hens to replace limestone: digestibility, productive performance and egg quality.

Our objective was to determine whether inclusion of industrial egg residue (IER) in the diets of laying hens would replace calcitic limestone without interfering with productive efficiency, egg quality or digestibility. In a first study (Experiment I), we used 30% IER in the diets of laying hens and found that the apparent digestibility coefficients were 51.6%, 42.8%, 51.6% and 17.8% for dry matter, crude protein, calcium and phosphorus, respectively. In the second study (Experiment II), we compared a control diet containing calcitic limestone with four diets containing increasing levels of IER, in proportions of 25%, 50%, 75% and 100%. During the first cycle (day 1-28), there was no difference between treatments in terms of productive performance or egg quality. During the second production cycle (day 29-56), we observed less food consumption by birds that ingested the highest levels of IER (100% substitution) than in controls. During the third cycle (day 57-84), we found that the inclusion of IER negatively affected performance, particularly lower production numbers, lower egg mass and higher feed conversion. Finally, during the third cycle, chickens broke and ingested their eggs shortly after laying. We conclude that the use of industrial egg residue cannot replace limestone in the feed of commercial laying hens, because it reduces performance and affects egg quality.

Effect of heat treatment on pre-stocking of Turkey eggs and its impact on incubation and hatching.

Egg stocking is used to meet housing demands in the hatchery industry. Stocking periods longer than 10 days of occur commonly, despite the fact that this practice causes productive losses during the incubation process. To minimize these losses, eggs are heated before incubation to stimulate the embryo, thereby reducing the range of birth intervals. The objective of this study was to determine whether heat treatment (37.5 °C) prior to incubation would improve hatching rates. We also determined the heat-exposure time necessary to improve productivity. We stored 5376 Nicholas pedigree eggs, aged between 40 and 51 weeks, for seven days. These eggs were distributed in three groups: groups 1 and 2 received 4 and 6 h of heat treatment, respectively; group 3 was used as control (no heat treatment, remaining at 17 °C). After heat treatment, the eggs were stored for 7 days at 17 °C, together with eggs from the control group. We found significant variation in the cumulative dispersion of birds born during the hatch window; greater numbers of birds were born in group 1 that underwent the 4-h heat treatment with a 24-h hatch window and in group 3 that underwent the 6-h heat treatment with a 12-h hatch window. Hatch rate, yolk retention and the relationship between average chick weight/average egg weight did not differ between treatments. These data suggest that heat treatment modulates the hatch window; nevertheless, the treatment did not influence the average weight the chicks, the number of chicks born, the percentage of hatching or yolk retention.

Correlation between intestinal health and coccidiosis prevalence in broilers in Brazilian agroindustries.

Coccidiosis is caused by protozoa of the genus Eimeria. These are intracellular parasites of enterocytes that rupture the host cell, causing lesions in the intestinal mucosa. The lesions caused by Eimeria reduce nutrient absorption capacity, negatively affecting productive gains in broilers, and representing a gateway for other enteropathogens. The objective of this study was to analyze the correlation between lesions caused by Eimeria and the prevalence of coccidiosis and other alterations found in the gastrointestinal tracts of broilers produced in Brazil from 2017 to 2018. Intestinal health evaluations were performed in 32 integrations (farm) of broilers in Brazil, totaling 726 birds analyzed between the ages of 22 and 40 days. Necropsied chickens were collected at three different points, with at least three birds per shed. We analyzed the following changes in the gastrointestinal tract: presence of cellular desquamation, fluid and mucus excess, ingestion of bedding, small and large intestine lesion, food passage, altered tone, "Turkish towel" lesions, worm infection, enteritis and gizzard erosion. The definition of macroscopic lesion scores caused by Eimeria acervulina, Eimeria maxima, Eimeria tenella followed a specific methodology. Mucosal oocyst counts for E. maxima (E. maxima micro) was performed using an optical microscope with a magnification of 100×. We found that the species E. acervulina had the highest prevalence (5.5%). With respect to E. acervulina, a positive correlation was observed with cellular desquamation, bedding ingestion and passage of food. The second highest prevalence was E. maxima (average of 4%), showing positive correlations with cellular desquamation, fluid excess, bed ingestion, feed passage and E. acervulina. E. tenella represented the lowest prevalence (0.8%) among the species of Eimeria analyzed, showing a positive correlation with altered intestinal tone. On microscopic evaluation, E. maxima was present in 45% of mucosa scrapings, representing subclinical coccidiosis of 1125% (11.25-fold) greater than the rate of clinical coccidiosis. Regarding other alterations that were visualized in the gastrointestinal tract, we have recorded the incidence of altered intestinal tone (0.1%), worm infection (0.4%), small intestine (0.8%), enteritis (1%), duodenitis (1.5%), "Turkish towel" lesions (3.3%), excess fluid (4.5%), bed ingestion (6.9%), excess mucus (8.4%), food passage (10.3%), cellular desquamation (11%) and gizzard erosion (13.4%). We conclude that monitoring is of paramount importance to understand the intestinal health status of poultry lots. Microscopic E. maxima is present in 45%. We identified factors that correlate with reduction in intestinal health, impairing zoo-economic performance.

Oregano essential oil in the diet of laying hens in winter reduces lipid peroxidation in yolks and increases shelf life in eggs.

We evaluated the effects of oregano essential oil (OEO) added to the feed of semi-heavy laying hens during winter. We measured performance as well as physical and chemical quality of fresh and 21-day stored eggs. A total of 240 semi-heavy laying hens were distributed into six treatments and five replicates (n = 8 each). Treatments consisted of five groups of hens fed diets supplemented with 0, 50, 100, 150 and 200 mg OEO/kg. We measured the average of three productive cycles (1st: week 1-4, 2nd: week 5-8 and 3rd: week 9-12), and found that feed consumption increased in hens in the control group and those in the group treated with 200 mg OEO/kg; other zootechnical variables did not differ between treatments. When we analyzed each individual production cycle individually, we did not observe differences between treatments for the performance variables in the first or second cycles. However, in the third cycle, when the animals were exposed to a greater number of days to cold stress, we recorded improved conversion rate/dozen eggs, conversion rate/daily feed consumed and egg production at T50 (50 mg OEO/kg). Stored eggs from hens supplemented with 50 mg OEO/kg showed lower eggshell percentages and higher yolk pHs. The intensity of the yellow was higher in yolks of the control group and in those from hens supplemented with 200 mg OEO/kg. Lipid peroxidation was lower in fresh egg yolks from hens that received 200 mg OEO/kg and stored eggs of T150. The reduction of lipid peroxidation in egg yolk is beneficial to consumer health by reducing levels of free radicals consumed. Reduction of lipid peroxidation associated with 150 mg OEO/kg in laying hens in winter might be useful for maintaining egg quality and for prolonging shelf life; productive efficiency was improving even at 39.8 mg OEO/kg if we consider feed conversion (kg/kg).

Spirulina platensis in Japanese quail feeding alters fatty acid profiles and improves egg quality: Benefits to consumers.

The aim of this study was to investigate whether microalgae in Japanese quail feed alters performance, fatty acid profiles in the eggs and egg quality. One hundred quails were distributed in four groups and five replicates of five birds per experimental group. The treatments consisted of four levels of Spirulina platensis microalgae (0%, 5%, 10%, and 15%) in the diets. We evaluated the productive performance and chemical-physical characteristics of eggs, the oxidant/antioxidant status in egg yolks, and the fatty acid profile in the diet and egg yolks. Microalgae in the diet did not influence egg production; however, it increased the yolk index as well as the color intensity of the yolk. Saturated and polyunsaturated fatty acid levels decreased in egg yolks, and monounsaturated fatty acid levels increased in the yolks. Lipid peroxidation levels were lower and total antioxidant capacity was higher in egg yolks of quails receiving microalgae in the diet. PRACTICAL APPLICATIONS: Microalgae in quail diets improves egg quality and provides benefits to consumer health, acting as an antioxidant and immune-stimulant. Microalgae in quail diets had positive effects on egg quality. This is because it reduced levels of saturated fatty acids that are undesirable, and increased monounsaturated fatty acid levels that are beneficial to the health of consumers. Finally, antioxidants increased in egg yolks, consequently reducing lipid peroxidation.

Spray-dried porcine plasma added to diets contaminated with aflatoxins and fumonisins shows beneficial effects to piglet health.

This study was aimed to analyze the effects of spray-dried porcine plasma (SDPP) on the health of post weaning piglets challenged with diets contaminated with aflatoxins and fumonisins. Fifty-six male piglets (7.15 ± 0.61 kg) were allocated in four groups: CTL group received a regular diet; SDPP group received a regular diet and 6% SDPP; MYC group received a diet containing 300 µg/kg aflatoxins and 8,000 µg/kg fumonisins; group MYC+SDPP received 300 µg/kg aflatoxins, 8,000 µg/kg fumonisins and 6% SDPP. The animals that received the experimental diet containing mycotoxins (MYC group) had lower weight gain at the end of the experiment compared to the other treatments. Animals receiving SDPP showed decreased urea levels throughout the experiment (P<0.05). Animals from MYC group presented an increased on reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels and decreased catalase activity (P<0.05). In contrast, SDPP prevented the increase of ROS and TBARS and stimulated superoxide dismutase activity (P<0.05). In conclusion, diet contaminated with mycotoxins (group MYC) caused subclinical intoxication in the piglets, as observed by the increase on free radical's production and lipid peroxidation. Conversely, SDPP presented a protective effect, minimizing the effects of oxidative stress caused by aflatoxins and fumonisins ingestion.

Genetic parameters for growth characteristics of free-range chickens under univariate random regression models.

Repeated measures from the same individual have been analyzed by using repeatability and finite dimension models under univariate or multivariate analyses. However, in the last decade, the use of random regression models for genetic studies with longitudinal data have become more common. Thus, the aim of this research was to estimate genetic parameters for body weight of four experimental chicken lines by using univariate random regression models. Body weight data from hatching to 84 days of age (n = 34,730) from four experimental free-range chicken lines (7P, Caipirão da ESALQ, Caipirinha da ESALQ and Carijó Barbado) were used. The analysis model included the fixed effects of contemporary group (gender and rearing system), fixed regression coefficients for age at measurement, and random regression coefficients for permanent environmental effects and additive genetic effects. Heterogeneous variances for residual effects were considered, and one residual variance was assigned for each of six subclasses of age at measurement. Random regression curves were modeled by using Legendre polynomials of the second and third orders, with the best model chosen based on the Akaike Information Criterion, Bayesian Information Criterion, and restricted maximum likelihood. Multivariate analyses under the same animal mixed model were also performed for the validation of the random regression models. The Legendre polynomials of second order were better for describing the growth curves of the lines studied. Moderate to high heritabilities (h(2) = 0.15 to 0.98) were estimated for body weight between one and 84 days of age, suggesting that selection for body weight at all ages can be used as a selection criteria. Genetic correlations among body weight records obtained through multivariate analyses ranged from 0.18 to 0.96, 0.12 to 0.89, 0.06 to 0.96, and 0.28 to 0.96 in 7P, Caipirão da ESALQ, Caipirinha da ESALQ, and Carijó Barbado chicken lines, respectively. Results indicate that genetic gain for body weight can be achieved by selection. Also, selection for body weight at 42 days of age can be maintained as a selection criterion.