Does the marketing age impact growth performance, carcass traits, economic feasibility and hemato-biochemical properties of genetically-modified quails?

The meat of the quail is one of the most delicious types, as it is rich in minerals and vitamins, especially vitamin K, which is useful in treating nervous diseases. In the present investigation, based on their live body weight, 270 genetically-enhanced white quail chicks of mixed sex were randomly assigned to 3 groups, each with 90 chicks. The first group's birds were slaughtered at 28 d of age. The birds in the second group were slaughtered at 31 d, and the birds in the third group were slaughtered at 34 d. Results showed no significant difference between the various groups in the overall mortality rate index at the end of each fattening stage (P > 0.05). There were substantial variations (P ≤ 0.05) in the average live weight index between the first and both groups at each group's marketing age. With increasing marketing age, body weight increases. Quail chicks raised for 34 d received the lowest EPEF (28.90 points), followed by those raised for 31 d and 28 d, which received 33.37 and 37.32 points, respectively. The economic feasibility of the 3 groups, no significant differences in the profit index were observed at the age of 28 d. Compared to the marketing age of the other 2 groups, it was noted that the profit index decreased as the birds advanced in age. Delaying marketing to 31 d leads to a decrease in profit by 5.7%, and delaying marketing to 34 d reduces the profit index to 26.36% compared to marketing at 28 d. For blood hematology parameters, a significant increase in the studied indicators with the age of the birds was observed through the study of blood indicators. Still, it did not reach the significance level. It could be concluded that 28 d is the ideal marketing age for the enhanced white quails, as it yielded the highest economic return and the best performance.

Age-related changes in testicular histological structure, testosterone level, libido and semen traits in male Coturnix quail

To investigate the effect of age in male quail on testicular weight and histology, sexual libido and semen characteristics, a study was performed on 100 quails at 10, 16, 22, 28 and 34 weeks of age. The body and testicular weights were significantly (p < .05) higher at 16 and 22 than at 28 weeks of age. The circumference and diameter of the seminiferous tubules were significantly (p < .05) higher at 28 and 34 than at 10 and 16 weeks of age. Histological evaluation of testicular slices revealed advanced and effective seminiferous tubes as early as 10 weeks, while spermatogenic activity peaked at 16 weeks of age. The highest semen volume, sperm motility and sperm concentration were observed at weeks of age and then decreased gradually with age. At the same time, the testosterone level and libido were significantly (p < .05) higher at 22 than at 10 weeks of age. Furthermore, the age was positive (p < .05), correlated to seminiferous tubule circumference and diameter, and negative (p < .05), correlated to sperm concentration. In conclusion, the age of quail markedly affected the testicular histological structure, libido, testosterone level and semen characteristics.

Impacts of willow (Salix babylonica L.) leaf extract on growth, cecal microbial population, and blood biochemical parameters of broilers

The investigation examined the use of willow leaf extract (WLE) on broiler chickens, examining carcass characteristics, cecal microbiota, antioxidants, and blood parameters. In 4 groups of 300 chicks, a basal diet was given for 5 wk, and the first treatment was basal diet (C). The diets for the remaining 3 treatments (WLE150, WLE300, and WLE450) contained 150, 300, and 450 mg of willow leaf extract /kg, respectively. The study found that birds fed willow leaf extract supplements had significantly greater body weight (BW), body weight gain (BWG), and enhanced feed conversion ratio (FCR) vs. the control group. Birds fed at 450 mg/kg food showed the greatest growth features, carcass weight, liver weight, lower abdominal fat, better low-density lipoprotein (LDL), and high-density lipoprotein (HDL) concentrations, and highest hematological characteristics. Chickens fed diets supplemented with varied doses of willow leaf extract showed significantly increased antioxidant enzyme activity, with higher amounts of glutathione peroxidase (GPx) activity, superoxide dismutase (SOD), total antioxidant capacity (TAC), and lower malondialdehyde (MDA). However, in the study, birds fed a diet supplemented with 450 mg of willow leaf extract per kg meal showed a significant drop of 13.02%, which found no significant variations in hazardous bacteria (Escherichia coli) across 2 treatments (WLE150 and WLE300). In addition, the study discovered that birds fed with varied doses of willow leaf extract had fewer cecum infections (Staphylococci aureus). We conclude that using willow at a level of 450 mg/kg diet can significantly enhance the BWG, FCR, antioxidant levels and beneficial bacteria activity besides the condition of broiler chicken's general health.

Application of botanical products as nutraceutical feed additives for improving poultry health and production

Poultry is one of the most consumed sources of animal protein around the world. To meet the global demands for poultry meat and eggs, it is necessary to improve their nutrition to sustain the poultry industry. However, the poultry industry faces several challenges, including feedstuff availability, the banning of antibiotics as growth promoters, and several environmental stressors. Therefore, there is a critical need to include available nutraceuticals in the diet to sustain the poultry industry. Nutraceuticals are natural chemical substances that positively influence animal physiological and productive traits. Botanical products (such as fenugreek seeds, ginger roots, and olive leaves) are among the most commonly used nutraceuticals and are gradually gaining popularity in the poultry industry due to their immense benefits in nutrition and therapeutic properties. They can be added to the diet separately or in combination (as a natural antioxidant and immunostimulant) to improve poultry health and production. Botanical products are rich in essential oils and essential fatty acids, which have multiple benefits on the animal's digestive system, such as activating the digestive enzymes and restoring microbiota balance, enhancing poultry health, and production. These nutraceuticals have been shown to stimulate the expression of several genes related to growth, metabolism, and immunity. In addition, the essential oil supplementation in poultry diets up-regulated the expression of some crucial genes associated with nutrient transportation (such as glucose transporter-2 and sodium-glucose cotransporter-1). Previous studies have suggested that supplementation of botanical compounds increased broiler body weight and hen egg production by approximately 7% and 15%, respectively. Furthermore, the supplementation of botanical compounds enhanced the reproductive efficiency of hens and the semen quality of roosters by 13%. This review article discusses the significant effects of some botanical products in the poultry industry and how they can benefit poultry, especially in light of the ban on antibiotics as growth promoters.

Effect of essential oils on the immune response to some viral vaccines in broiler chickens, with special reference to Newcastle disease virus

This trial assessed the efficacy of a commercial essential oil (EO) product on the immune response to vaccination against Newcastle disease (ND) and subsequent challenge with virulent ND virus genotype VII (vNDv genotype VII) by using the following experimental groups of broiler chickens (Each group had 21 birds with 3 replicates in each, n = 7): NC (negative control), PC (positive control), VC (vaccinated), and VTC (vaccinated and treated with EOs). Moreover, in a trial to study the effect of EOs on vNDv genotype VII in vivo as a preventive or therapeutic measure, 2 additional ND-vaccinated groups were used (PRV: medicated 1 D before vNDv challenge for 5 D; and TTT: medicated 2 D after vNDv challenge for 5 D). In addition, the immune-modulatory effect of EOs on the avian influenza (AI), infectious bronchitis (IB), and infectious bursal disease (IBD) vaccines was assessed through the serological response. The use of EOs along with administration of ND vaccines (VTC) revealed a lower mortality rate (42.86%), clinical signs, and postmortem lesion score (11) than ND vaccines alone (VC) (52.28% mortality and score 15), in addition to lower hemagglutination inhibition (P < 0.05) (6.5 ± 0.46) and viral shedding (10 log 2.28 ± 0.24) titres 1 wk after challenge in comparison with VC (8.63 ± 0.65 and 10 log 3.29 ± 0.72, respectively). Nevertheless, the EOs mixture (VTC) (1952 ± 28.82) did not significantly (P > 0.05) improve growth performance compared with the nontreated birds (NC and VC) (1970 ± 19.56 and 1904 ± 38.66). EOs showed an antiviral effect on vNDv in vivo (in chickens) as a preventive measure (PRV) as well as some therapeutic effect (TTT) through decreasing the viral shedding titres (loNC₀), mortality rate, and severity of clinical signs and postmortem lesions, in addition to serum malondialdhyde level. Regarding the other viruses, the EOs mixture did not improve the immune response to the AI and IB vaccines but significantly (P < 0.05) increased the ELISA antibody titre for IBD virus at the 28th D of age (2,108 ± 341.05). The studied EOs mixture showed an immune-stimulating response to ND and IBD vaccines, antiviral effect against ND virus, especially if administered before the challenge; however, it did not have a growth-promoting effect.

Growth, carcass traits, cecal microbial counts, and blood chemistry of meat-type quail fed diets supplemented with humic acid and black cumin seeds

OBJECTIVE

The present study attempted to determine safe and sufficient growth promoters in poultry feeding.

METHODS

A total of 520 seven-day-old quail chicks were randomly allotted to eight treatment groups in a 4×2 factorial design experiment to evaluate the effect of different levels of humic acid (HA) and black cumin (BC) seed and their interactions on growth, carcass traits, gut microbes, and blood chemistry of growing quails. Quails were randomly distributed into 8 groups in a 4×2 factorial design, included 4 HA levels (0, 0.75, 1.5, and 2.25 g/kg diet) and 2 BC levels (0 or 5 g/ kg diet).

RESULTS

Increasing HA level associated with a gradual increase in final weight, feed intake and body weight gain along with an improvement in feed conversion ratio. Dietary addition of 5 g BC powder/kg diet gave similar results. The highest level of HA (2.25 g/kg diet) recorded the best values of carcass weight, breast yield, intestinal length, and intestinal weight comparing with the control and other HA levels. Total viable microbial counts decreased (p<0.05) with increasing levels of HA except the intermediate level (1.5 g/kg diet). The concentration of serum cholesterol and low density lipoprotein (excluding that 0.75 g HA) decreased (p<0.05) and high density lipoprotein increased (p = 0.034) along with increasing HA level. The interaction between the 2.25 g HA×5 g gave the best results regarding most studied parameters.

CONCLUSION

These findings indicated that HA combined with BC could be used as effective growth promoters, with the recommended level being 2.25 g HA+5 g BC/kg of quail diet.