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.

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.

Oregano essential oil (Origanum vulgare) to feed laying hens and its effects on animal health.

This study evaluated the effect of oregano essential oil added to the feed of commercial laying hens. This research was focused on the analysis of biochemical changes linked to hepatic function, and protein and lipid metabolism. It was used 240 laying hens (59 weeks-old) distributed in a completely randomized design of six treatments (five repetitions with eight birds each). The experiments were constituted by a control treatment (CT) with the inclusion of zinc bacitracin and five treatments of oregano essential oil (OEO: 0, 50, 100, 150, and 200 mg.kg-1), respectively. After 28 days of feeding, an increase on serum levels of total proteins and globulins was observed on groups T150 and T200, as well as an increase on albumin levels on group CT. After 84 days of feeding, a significant reduction on total proteins and albumin was observed on group T200, as well as an increase in serum triglycerides. OEO at 200 mg.kg-1 increased globulin levels on day 28, which may be considered an effect in the inflammatory response, which increases serum immunoglobulins and proteins.

Addition of grape pomace flour in the diet on laying hens in heat stress: Impacts on health and performance as well as the fatty acid profile and total antioxidant capacity in the egg.

The aim of this study was to evaluate whether the addition of grape pomace flour (GPF) in the diet of laying hens at the end of the productive cycle and on heat stress could exert benefits on their health and performance, as well as egg quality. For this, 74-week-old laying hens (n = 64) were divided into four groups with four repetitions each, as follow: T0 (the control group; without GPF), T1 (1% GPF), T2 (2% GPF) and T3 (3% GPF) during 35 days. Percentage of laid eggs was higher in the group T1 compared to T0, and the feed intake was higher in the groups T1, T2 and T3 compared to T0. There was no difference regarding the chemical-physical composition of fresh eggs; however, eggs from GPF-fed chickens showed changes after storage regarding specific gravity, yolk index, pH of yolk, albumen and Haugh unit compared to T0. Fresh or stored egg yolk from GPF groups showed higher antioxidant capacity and lower lipid peroxidation compared to T0. GPF (3%) prevented the reduction of monounsaturated fatty acids in the yolk of stored eggs compared to T0. Glutathione peroxidase and superoxide dismutase activities, as well as total antioxidant capacity against peroxyl radicals were higher in the serum of laying hens that received GPF compared to T0, while lipid peroxidation was lower. In summary, the addition of GPF in the diet for laying hens at the end of the productive cycle can be beneficial for animal health and exerted positive effects in their performance and egg quality.

Glycerol monolaurate in the diet of broiler chickens replacing conventional antimicrobials: Impact on health, performance and meat quality.

Glycerol monolaurate (GML), known as lauric acid, is a chemical compound formed from lauric acid and glycerol that presents strong antimicrobial activity. Therefore, our hypothesis is that MGL can replace conventional antimicrobials, being a new alternative to poultry farming. The aim of this study was to evaluate whether the addition of GML as a replacement for antibiotics could have positive effects on health and performance of broiler chickens. For this, 240, one-day-old, Cobb 500 broiler chicks were weighed and randomly distributed into four groups with four repetitions each (n = 15). The control group, T0, received a basal diet containing antibiotic (60 ppm of bacitracin), while the T100, T200, and T300 groups received a basal diet supplemented with 100, 200, and 300 mg/kg of GML, respectively. The birds were weighed at intervals of seven days, as well as at the end of the experiment (day 42). Blood samples were collected for evaluating animal health, stool for counting bacteria and coccidian, as well as muscle (chest) to measure meat quality, respectively. At the end of the experiment (day 42), body weight, weight gain, and daily weight gain of broiler chickens in the T300 group were higher than the T0 group (P < 0.05). Indeed, feed conversion was lower compared to T0. Animals that received diets containing GML showed lower amounts of Eimeria spp. oocysts on day 42 in comparison to the control group. Low total bacterial counts on day 21 of the experiment were also observed in the treated groups. Conversely, plasma levels of total protein, globulins, uric acid, and glucose were higher in animals that received GML when compared to the control group. It was also observed higher carcass yields in the breast muscle of the T100 group when compared to other groups. Lower water holding capacity was observed in breast meat of animals of the groups T100, T200, and T300 when compared to T0. Histopathological findings were compatible with coccidiosis, and the degree of these lesions did not differ among groups. Based on these results, GML in the diets of broiler chickens, showing potent antimicrobial effect, growth promoter capacity, and lack of toxicity. Therefore, GML is a promising alternative to replace conventional antimicrobials used in the diets of broiler chickens.

Effects of phytogenic feed additive based on thymol, carvacrol and cinnamic aldehyde on body weight, blood parameters and environmental bacteria in broilers chickens.

The aim of this study was to evaluate whether a phytogenic feed additive (PFA) based on essential oils such as carvacrol, thymol and cinnamic aldehyde, could be considered a replacement for antimicrobials used as growth promoters in broiler chickens, as well as to investigate its effect on total bacterial count, biochemical profiles, meat quality and meat fatty acid profile. A total of 240 broiler chicks were randomly distributed into 4 groups with 4 replicates of 15 animals each, as follow: T1 (basal diet only; the control group), T2 (basal diet supplemented with zinc bacitracin), T3 (basal diet with 0.5% of the PFA), T4 (basal diet with 1.0% of the PFA). The addition of 0.5% of the PFA improved live body weight of supplemented birds compared to the control group at 35 and 42 days of age, while the total bacterial count in the environment was reduced when 1.0% of the PFA was used. In addition, intestinal villi height and crypt depth suffered variations during the entire experiment in birds treated with both concentrations of the PFA and zinc bacitracin. Total erythrocyte counts were higher on days 14, 28 and 42 in both treated groups (PFA) compared to the control group, as well as hemoglobin content on days 28 and 42. On the other hand, leukocyte counts were lower on days 14, 28 and 42 due to reduced lymphocyte counts in both PFA treated groups compared to the control group. Serum levels of alanine aminotransferase (ALT) were lower in broilers fed with either concentration of PFA on day 14 of life, and the same was observed regarding aspartate aminotransferase (AST) in broiler treated with 0.5% of the PFA. Also, total protein and globulin levels were lower on days 14 and 28 in groups fed with phytogenic compared to the control group. Regarding meat quality, breast meat showed higher red intensity and shear force in groups fed with both concentrations of phytogenic compared to the control group, while weight loss by cooking was lower. Finally, 1.0% of phytogenic showed lower docosadienoic acid (C22:2) content in breast meat. In conclusion, results showed that the use of PFAs based on carvacrol and thymol may be considered an interesting alternative to increase broilers performance, replacing the use of antimicrobials as growth promoters, as well as an interesting alternative to reduce the total bacterial count in the environment of broiler chickens. Moreover, the diet containing phytogenic also showed hepaprotective effects but deserves attention regarding possible alterations on the immune response.