M.E. Abd El-Hack

Standardized ileal amino acid digestibility of meat and bone meal and soybean meal in laying hens and broilers.

The objective of this study was to determine the standardized ileal amino acid digestibility (SIAAD) of 7 meat and bone meal (MBM) and 3 soybean meal (SBM) samples in broilers (Ross 708) and laying hens (Hy-line W36). All 10 feed ingredients were evaluated in 21-d-old broiler chickens and 30- or 50-wk-old laying hens. Standardization was accomplished by correcting for basal ileal endogenous amino acid losses using a nitrogen-free diet. Broilers were reared in cages from d 0 to 16 on a standard broiler starter diet adequate in all nutrients and energy; thereafter, they were allotted to treatments using a randomized complete design with 6 replicate cages of 8 birds each. For the laying hens, 6 replicate cages of 6 birds each (542 cm(2)/bird) were used. Each treatment diet, which was fed for 5 d, was semipurified, with MBM or SBM being the sole source of amino acids in each diet. Ileal endogenous amino acid losses were not different between broilers and the 2 groups of laying hens. Meat and bone meal from different locations varied widely in digestibility. Broilers had higher (P < 0.05) SIAAD in 4 of the 7 MBM samples. In 2 of the 3 SBM samples, broilers had higher (P < 0.05) SIAAD for most of the nonessential amino acids. Generally, hens had 6.4 and 7.7% units less Met and Lys digestibility of all MBM samples after standardization. Dry matter digestibility values of the SBM samples were higher (P < 0.05) in broilers. Likewise, broilers had 4.1 and 1.5% units more Met and Lys digestibility of all the SBM samples evaluated compared with those from laying hens. The results of these experiments suggest that differences exist in the digestive capabilities of laying hens and broilers, which indicates that species-specific nutrient digestibility values or adjustments may be needed.

Quercetin: Nutritional and beneficial effects in poultry

Flavonoids are natural compounds derived from fruits, vegetables and medicinal plants. These compounds have been reported to possess various biological actions including anti-inflammatory, antioxidant, growth promoter, antiviral, hepatoprotective, antibacterial, antiallergic, anticarcinogenic, antithrombotic and immunomodulator activities in various animals and poultry species. Quercetin is found in various foods such as vegetables, tea, fruits, wine apples and onions and is known to exert positive effects on poultry production and health. Since, quercetin enhances the immune system by stimulating lymphocytes, macrophages and IgY antibody production and improving natural killer cell activity, lymphoid organs (spleen, thymus and bursa) weights as well as activating the cytokines profile, its supplementation can lead to a state of immune alertness and a lower incidence of infections and diseases. In addition, it affects the dendritic cells (DCs) that play an important role in adaptive and innate immunity. Quercetin revokes the ability of lipopolysaccharide (LPS)-stimulated dendritic cells to induce specific T cell activation and reduce the cytotoxicity in both in vivo and in vitro studies, suggesting quercetin works as an immunosuppressive agent. As immune function is crucial for poultry productivity and prosperity, this review elucidates the potential nutritional effects and health benefits of quercetin on poultry as a replacer for traditional immune boosters and growth promoters. It includes the antiviral activity of quercetin against influenza A virus, rhinovirus (caused common cold), adenovirus (source of necrotic pancreatitis in broilers) and suggests its role in counteracting heavy metal toxicity. However, further studies on molecular basis are required to understand mode of action, beneficial applications as a natural feed additive, growth promoter and immune enhancer, beside the side effects of this compound in poultry.

Heat stress: effects on productive and reproductive performance of quail

Animals experiencing thermal stress tend to reduce heat production by limiting feed intake, with subsequent detrimental impacts on productive performance and health status. Heat stress as an environmental stressor has been an important concern among researchers, poultry producers and scientists for many decades, especially in tropical (wet and hot round the year) and arid (dry and hot round the year) regions of the world. It has been implicated in adverse marked impacts on productive and reproductive performance of quail. Several studies have investigated the negative impacts of heat stress on quail production and it has been shown that heat stress adversely affects both productivity and welfare of birds. The deleterious impacts of heat stress on different quail breeds such as Japanese quail (Coturnix coturnix japonica), bobwhite quail (Colinus virginianus), scaled quail (Callipepla californica) and Gambels quail (Colinus gambelii) range from decreased body weight (7.7 to 13.2%), growth rate (11.0 to 14.5%), feed intake (6.1 to 21.6%), feed efficiency (4.3 to 8.6%), egg production (6.6 to 23.3%) and egg mass. Furthermore, the detrimental effects of heat stress on reproductive performance and welfare of quail have recently attracted awareness. However, further studies are required to increase the levels of information into basic mechanisms associated with the consequences of heat stress on quail. This review covers the published evidence available on the negative role of heat stress on growth performance, feed utilisation, egg production and mass, meat and egg quality and carcass traits as well as reproductive performance of quail.

Feeding time can alleviate negative effects of heat stress on performance, meat quality and health status of turkey

ABSTRACT 1. A total of 180 one-day-old turkeys were randomly assigned to 6 equal groups to investigate the effect of feeding time on growth performance, carcass characteristics, meat quality, leg problems and physiological responses of growing turkeys under the high temperature conditions of summer. 2. Birds of the first group were ad libitum fed and were considered as the controls (C). The second group (T1) was given 80% of diet in the morning and 20% of diet in the afternoon, the third group (T2) was given 60% of diet in the morning and 40% of diet in the afternoon, the fourth group (T3) was given 40% of diet in the morning and 60% of diet in the afternoon, the fifth group (T4) was given 20% of diet in the morning and 80% of diet in the afternoon and the sixth group (T5) was given 100% of diet in the afternoon. 3. Body weight, body weight gain and feed conversion ratio were improved with T2, T3, T4 and T5 in comparison to control or T1 under heat stress conditions. No significant impacts on carcass traits and meat quality due to changing the time of feeding were seen, except for tenderness and juiciness. 4. Feeding in the afternoon (100%) decreased body temperature and tonic immobility test score, which were positively related with the health condition of the birds. 5. The incidence of leg problems, plumage condition and breast blisters were not significantly different among the experimental groups. 6. It is concluded that feeding turkeys mainly or totally in the afternoon (T4 and T5, birds were fed with 80% or 100% of the diet in the afternoon) can be used as a strategy and a managerial tool for improving growth rate, feed utilisation, carcass and meat quality, as well as health status of growing turkeys reared under hot climate conditions.

Wet feed and cold water as heat stress modulators in growing Muscovy ducklings

&NA; In an attempt to alleviate the deleterious effects of high summer temperatures, the present study investigated the effects of wet feed and cold water on the growth performance, carcass and meat quality, leg problems, physiological responses, and blood parameters of growing Muscovy ducklings. A total of 180 4‐week‐old ducklings was randomly divided into 6 experimental groups in a 3 × 2 factorial design that included 3 feed systems (AD: ad libitum dry; DW: diurnal wet; and AW: ad libitum wet) and 2 systems of water (TW: tap water; and CW: cold water). Access to wet feed and cold water affected the growth performance, dressed carcass, gizzard, meat quality (tenderness, juiciness, and susceptibility), tonic immobility, body temperature, and blood parameters [albumin: globulin (A: G) ratio and levels of glucose, alanine transferase (ALT), total antioxidant capacity (T‐AOC), and malondialdehyde (MDA)] of the ducklings but had no significant effect on plumage condition, shank length, keel bone length, leg problems, or breast blisters. The body weight (BW) of the DW group was 1.97 and 3.12% greater than that of the AD and AW groups, respectively, and the BWG of the DW group was 6.91 and 10.72% greater than that of the AD and AW groups, respectively. Therefore, providing access to wet feed and cold water is highly recommended when raising Muscovy ducks in open houses under high‐temperature conditions.

Jatropha (Jatropha curcas) meal is an alternative protein source in poultry nutrition

The application of novel feedstuffs in poultry diets, especially in developing countries, has received attention in recent years. Jatropha (Jatropha curcas) is a non-edible oil seed, and its meal is a rich in protein. Jatropha meal (JM) has been characterised as a potentially useful animal feedstuff due to its high content of crude protein level (35-50%), essential amino acid and mineral content. However, jatropha kernel contains high amounts of phytate, ranging from 7 to 10%, which would require phytase supplementation for it to be used in feeds. Jatropha contains toxic compounds and anti-nutritional factors, including lectin, tannin, saponin, phorbol esters and trypsin inhibitors, which require different treatments (physical, chemical or biological) to make it suitable for poultry diets. As a result of the presence of detrimental compounds, only low levels of jatropha in feed are recommended from animal trials. It may be used to partially substitute soybean meal, but not maize. It has been suggested in the literature that, after physical or chemical treatment of jatropha seed meal, it may have other benefits, including as an immunomodulant and antioxidant, as well as hypocholestermic, antihypertensive, hepatoprotectant, antiretroviral, anti-inflammatory, analgesic and antibacterial properties. It appears that heat and enzyme treated jatropha could be used in poultry diets without detrimental effects on productive and reproductive performance and may promote health status in poultry.

Influence of dietary inclusion of untreated or heat-treated Jatropha meal on productive and reproductive performances and biochemical blood parameters of laying Japanese quail

&NA; Jatropha meal (JM) has been characterized as a potential animal feedstuff due to its high crude protein content and high levels of essential amino acids. However, it contains anti‐nutritive and toxic compounds that may hinder its use. The present study was conducted to evaluate the effects of a dietary inclusion of raw Jatropha meal (RJM) and heat‐treated Jatropha meal on the growth and production of laying Japanese quail using productive, reproductive, and biochemical blood parameters. A total number of 180 mature Japanese quail at 2 months of age (120 females and 60 males) was randomly divided into 4 treatment groups: control (0% JM); 3.5% RJM; 3.5% JM heated in an oven at 100°C for 24 h (JM24); and 3.5% JM heated in oven at 100°C for 48 h (JM48). After 8 wk on treatment diets, the inclusion of RJM to quail diets reduced (P < 0.05) feed intake, feed efficiency, egg number, and egg mass compared with the control diet. There was no difference between the heat‐treated Jatropha (JM24 and JM48) treatments and the control. Fertility and hatchability percentages were improved (P < 0.001) with JM24 and JM48 compared with the RJM group. Feeding of 3.5% RJM or JM24 in quail diets led to significant decrease (P < 0.05) in serum total protein, albumen, globulin, &ggr;‐glutamyl transpeptidase, total and HDL‐cholesterol, immunoglobulin (IgG and IgM), and increased serum alanine transaminase (ALT) and creatinine along with the mortality rate when compared with birds fed JM48. In conclusion, heat treatment of JM is essential to eliminate its hepatotoxic and nephrotoxic effects and, when properly heat‐treated, can be used in laying Japanese quail diets without detrimental effects on production, reproductive performance, and health status.

Dietary supplementation of Yucca schidigera extract enhances productive and reproductive performances, blood profile, immune function, and antioxidant status in laying Japanese quails exposed to lead in the diet

ABSTRACT The present study investigated the toxic impacts of lead (LD) on the productive and reproductive performances of Japanese quails and the role of Yucca schidigera extract (YSE) in reducing these impacts. A total of 360 mature Japanese quails (at 2 months of age) were used and the experiment was lasted for 8 wk. The birds were divided into 6 equal groups as follows: control (basal diet), basal diet + 100 mg LD/kg diet, basal diet + YSE (100 mg/kg diet), basal diet + YSE (200 mg/kg diet), basal diet + LD (100 mg/kg diet) + YSE (100 mg/kg diet), and basal diet + LD (100 mg/kg diet) + YSE (200 mg/kg diet). LD resulted in a significant decrease in feed intake (FI), feed conversion ratio (FCR), and egg production of birds compared with the control group. Supplementation of YSE (100 or 200) to LD containing diet could significantly improve the quail performance parameters to be comparable with the control values. Fertility and hatchability % were decreased by LD, whereas YSE at both levels (100 or 200) separately or in combination with LD showed fertility and hatchability percentages comparable to that of control. Triglycerides, cholesterol, and LDL contents in LD plus YSE100 or LD plus YSE200 groups were significantly decreased than LD alone group. LD significantly decreased superoxide dismutase and catalase activities in the serum with no effect on reduced glutathione content. Co‐exposure to YSE100 or YSE200 with LD significantly increased the catalase activity and numerically increased the superoxide dismutase activity than LD alone. YSE100 or YSE200 decreased malondialdehyde contents than LD alone group. LD plus YSE100 or YSE200 groups exhibited significant improvements in the level of immunoglobulins. Co‐exposure to YSE with LD significantly decreased the LD residues in egg than the LD group. The obtained results showed that YSE exhibited a potential modulatory role against the LD‐induced inhibitory effects on the productive and reproductive performances of Japanese quails and YSE at 200 mg/kg diet was more effective than 100 mg/kg diet in reversing the LD‐induced alterations.

Use of acetylsalicylic acid as a feed additive in poultry nutrition

Salicylate plays an important role as a non-steroid, anti-inflammatory drug. In poultry, those used most commonly are sodium salicylate (SS) and acetylsalicylic acid (ASA), due to their immunomodulatory, analgesic, antipyretic, and anti-inflammatory activities. Other effects have been reported such as minimising the effects of heat stress, allostatic load, ascites, leg disorders, reducing respiratory and digestive disorders, as well as enhancing growth performance, feed utilisation, nutrient digestion and absorption, egg production and the quality of meat and eggs. Furthermore, ASA plays a key role in lowering cholesterol and triglycerides in blood, meat and eggs, and improvements in immune functions and antioxidant enzymes have been noted in birds. This paper reviews the different characteristics and beneficial applications of ASA in poultry nutrition for improving immunity, production, and safeguarding health, especially under heat stress conditions.

The beneficial uses of glycerin as an alternative energy source in poultry diets

Glycerin or glycerol (C3H5(OH)3) is one of the most valuable and versatile chemical materials known. The term ‘glycerin’ refers in general to a commercial solution of glycerol in water of which the main constituent is glycerol. Glycerin is an odourless, colourless, viscous liquid with a sweet taste. It is completely soluble in both alcohol and water. Glycerin is the main co-product derived from biodiesel production. It is produced by a KOH- or NaOH-catalysed transesterification of the triacylglycerols in fat or oil along with an alcohol. Glycerin is an important ingredient for the production of soaps, cosmetics, pharmaceuticals and food. Additionally, glycerin is highly stable under normal storage conditions, practically non-irritating in its different uses, suitable for interactions with other chemical materials and has no any negative environmental impacts. Nowadays, with increasing glycerin production and its availability on the market, many new and novel uses are expected to be developed, particularly as alternative energy source for poultry diets. Furthermore, glycerin plays an essential role in body cellular metabolism. This review paper discusses the various trials using glycerin in poultry diets as an energy source and its effects on different parameters in the birds. Generally, poultry diets, which included glycerin up to 10% in feed, gave positive responses in most of studies, some of which measured apparent metabolisable energy (AMEn). However, more indices need to be determined in further studies in different poultry species.