Zinc oxide nanoparticles preserve the quality and fertility potential of rooster sperm during the cryopreservation process

Sperm cryopreservation is one of the main methods for preserving rooster sperm for artificial insemination (AI) in commercial flocks. Yet, rooster sperm is extremely susceptible to reactive oxygen species (ROS) produced during the freezing process. Oxidative stress could be prevented by using nanoparticles containing antioxidants. The present study was conducted to investigate the effect of zinc oxide nanoparticles (ZnONP) in rooster semen freezing extender on quality parameters and fertility potential. For this aim, semen samples were collected and diluted in Lake extenders as follows: control: Lake without ZnONP, ZnO100: Lake with 100-μg zinc oxide (ZnO), ZnONP50: Lake with 50-μg ZnONP, ZnONP100: Lake with 100-μg ZnONP and ZnONP200: Lake with 200-μg ZnONP. After freezing and thawing, sperm motility, viability, membrane integrity, morphology, mitochondrial activity, acrosome integrity, DNA fragmentation, lipid peroxidation and ROS, as well as fertility and hatchability were assessed. According to the current results, higher rates of motility, membrane integrity, mitochondrial activity, acrosome integrity and live cells were detected in the ZnO100, ZnONP50 and ZnONP100 groups compared to other groups (p ≤ .05). Yet, the percentage of dead cells, DNA fragmentation, lipid peroxidation and ROS levels were lower in the mentioned groups (p ≤ .05). Furthermore, a higher percentage of fertility was observed in the ZnO100 and ZnONP100 groups than in the control group (p ≤ .05). In conclusion, the use of 100-μg ZnO and 50- to 100-μg ZnONP represents a valuable and safe additive material that could be used to improve the quality and fertility potential of rooster sperm under cryopreservation conditions.

Effects of day-of-hatch intramuscular administration of a herbal extract mixture and its re-supplementation in drinking water on growth performance, stress indicators, and antioxidant status of broiler chickens reared under hot summer conditions

Broilers under oxidative stress from high ambient temperatures may benefit from the use of additives that have antioxidant properties. This experiment investigated the efficacy of a herbal extract mixture (HEM; aqueous extracts from Ferula gummosa, Thymus vulgaris, and Trachyspermum copticum) in day-old chicks, injected intramuscular (deep pectoral muscle; (0, 30, 60, and 90 μL/0.1 mL of sterilized and distilled water)), and supplemented in drinking water (0 and 0.25 mL/L) during the rearing period. Broilers were reared in battery cages under summer temperature conditions, with average maximum temperature of 35.5°C, average minimum temperature of 25.5°C, and average relative humidity of 50-60%. A total of 400 1-day-old Ross 308 male broiler chicks were randomly assigned to 8 treatment groups (5 replicates/treatment with 10 birds per replicate). From d1 to d10, the indoor air temperature was adjusted to match fluctuating outdoor summer temperatures, and was set at 30-34°C and 50-60% relative humidity; and from d10 onwards, no adjustments were made. Injection of HEM linearly decreased feed:gain (P = 0.005), heterophile-to-lymphocyte (H/L) ratio (P = 0.007), and serum concentrations of cholesterol (P = 0.008), low-density lipoprotein cholesterol (LDL) (P < 0.001), malondialdehyde (P = 0.005), and cortisol (P = 0.008). The 60 μL of HEM injection produced the best results in terms of final body weight (BW; P = 0.003), overall average daily gain (ADG; P = 0.002), European performance index (P < 0.001), carcass yield (P < 0.001), and serum glutathione peroxidase activity (P < 0.001). Supplementation of HEM in drinking water also increased final BW (P = 0.048), overall ADG (P = 0.047), high-density lipoprotein cholesterol (P = 0.042), and total antioxidant capacity (P = 0.030), while decreasing the H/L ratio (P = 0.004) and serum LDL concentration (P = 0.031). There were interactions between injection and water supplementation for BW (day 24; P = 0.045), carcass yield (day 42; P = 0.014), and serum superoxide dismutase activity (day 42; P = 0.004). In conclusion, administering an injection of HEM at a dose of 60 μL at the time of hatching, followed by supplementation at a dose of 0.25 mL/L via drinking water during the rearing period could be a useful strategy for improving the performance and health status of heat-stressed broiler chickens.

Nutritional value of whole date waste and evaluating its application in ostrich diets

Although date waste products have been used as an alternative feed source in the diets of poultry for a long time, there is no quantitative information available regarding date waste used in ostrich diets. Therefore, two experiments were performed to evaluate the feeding value of whole date waste (WDW) as a feed ingredient in ostrich diets. In the first experiment, apparent metabolizable energy corrected to zero nitrogen balance (AMEn) of WDW was determined using 12 young ostriches (6 months old). The treatments included a reference diet and a test diet consisting of 60% of the reference diet and 40% of WDW. The AMEn of the WDW determined by total collection was 3216 kcal/kg. In the second study, four groups of eight growing ostriches (seven month old), with almost similar BW (60.4 ± 1.6 kg), were individually housed in outdoor paddocks of ≈24 m² and were tested from 7 to 9 months of age. The groups were fed four isocaloric (2420 kcal of AMEn/kg) and isonitrogenous (16.4% CP) diets containing 0, 10, 20, and 30% WDW. The results demonstrated that there were no significant differences among treatments in average daily feed intake, average daily gain, feed conversion ratio, and apparent total tract digestibility coefficients of DM, organic matter, energy, ether extract, ash, nitrogen-free extract, calcium, and phosphorus. In contrast, birds fed 0, 10, and 20% WDW diets had similar CP digestibility and this was significantly (P < 0.001) higher than that of birds on 30% WDW diet. The least crude fibre digestibility (P = 0.003) was also observed in birds fed 30% WDW diet. Blood RBC count, lymphocyte percentage, glucose concentration, and glutathione peroxidase activity increased linearly (P < 0.01), whereas heterophil percentage and heterophil-to-lymphocyte ratio decreased linearly (P = 0.002), in response to dietary inclusion of WDW. It can be concluded that WDW can be incorporated into the diets of ostrich chicks at levels of up to 30% without compromising growth performance. These results also suggest that WDW could be used as a feed ingredient for growing ostriches to improve stress-related variables and antioxidant status.

Efficacy of a phytonutrient supplement at different dietary protein contents on growth performance, gut morphology, digestive enzymes activities and stress indicators of broilers subjected to circular heat stress

Context Dietary manipulations such as reductions in protein or the addition of bioactive feed additives might alleviate the adverse effects of high ambient temperature in poultry. Aims The effects of dietary crude protein (CP) and phytonutrient mixture (PM) on growth performance and physiological responses were evaluated in broilers under circular heat stress (HS). Methods In total, 420 1-day-old broiler chickens were randomly distributed to seven treatments in a factorial arrangement (3 × 2), with three levels of CP (normal, medium (95% of the normal CP content) and low (90% of the normal CP content)) and with or without the addition of PM (mixture of 5 mg/kg carvacrol, 3 mg/kg cinnamaldehyde, and 2 mg/kg capsicum oleoresin). The thermoneutral control (TNC) birds were housed in a thermoneutral chamber and fed with a normal-CP diet without PM supplementation. The other six groups were kept in a HS chamber (33°C) for 8 h (1000 hours to 1800 hours). Key results After 6 weeks, feeding broiler chickens with low-CP diets had adversely affected growth performance and intestinal protease activities, while mortality rate, heterophile to lymphocyte ratio, and serum cortisol concentration of the low-CP group were lower (P &lt; 0.05) than those of the high-CP group. Dietary PM supplementation also positively influenced (P &lt; 0.05) average daily gain, feed conversion ratio, intestinal lipase and trypsin activities and serum T4 concentration. There were the CP × PM interactions (P &lt; 0.05) for jejunal villus height and villus surface area, indicating that the effect of PM on these responses was more marked at the lower dietary CP contents. Conclusions Supplementation with PM can ameliorate the detrimental effects of HS on productive performance and digestive enzyme activities in broilers. The PM supplementation could improve intestinal morphology when applied to the diets of heat-stressed broilers with lower CP contents (95% and 90% of the recommendations). Implications Although growth performance was reduced by feeding low-CP diets (90% of the normal CP content), a beneficial effect was observed on the stress indicators of broilers grown in HS conditions. Dietary supplementation of PM might also be an effective strategy to alleviate the adverse effect of HS.