Iris Kröger Technical Sales Manager Dr. Eckel Animal Nutrition GmbH & Co. KG

Maintaining laying performance in older breeder hens is a key to ensure farm profitability. A new trial investigating the effects of anti-oxidative and anti-inflammatory plant compounds indicates their great potential in enhancing performance, fertility and egg quality.

INTRODUCTION After the peak of egg production breeder hens usually show a reduction in performance and fertility. Previous studies showed that free radicals leading to lipid oxidation and chronic inflammation play an important role in this process. Therefore, modifying energy metabolism and protecting reproductive tissue from oxidative and inflammatory stress are key factors to maintain egg production and fertility in older breeder hens.

Previous findings indicate that besides optimal management and energy supply, extracts from green tea or grapes may protect breeder hens against oxidative and inflammatory stress to support their performance and fertility. Thus, flavonoid-rich plant compounds showed potent antioxidant and anti-inflammatory activity in vitro and in vivo (Gessner et al., 2017; Ricardo de Silva et al., 1991; Tipoe et al., 2007). Furthermore, plant compound from hops may improve performance of breeder hens, because feeding hops can improve feed efficiency in poultry (Cornelison et al., 2006).

Besides their antioxidant and anti-inflammatory effects, flavonoid-rich plant compounds showed performance enhancing effects in different species including layers and breeders. Thus, Kara et al. (2016) showed that supplementation of grape pomace to layer diets significantly increased egg weight. In addition, green tea increased egg production and feed conversion in breeder hens (Zeinab et al., 2010). The combination of different plant compounds generally unfolds more effects than single components. Therefore, the effects of Anta^®Ox FlavoSyn, a feed additive containing flavonoids mainly from hops, grapes and green tea, in older Sinai breeder hens was tested.

OVERCOMING PERFORMANCE DEPRESSION IN OLDER BREEDER HENS

MATERIALS AND METHODS The current study was conducted at the El-Serw Poultry Research Station, Animal Production Research Institute, Agriculture Research Center, Egypt.

A total number of 60 Sinai laying hens (47 weeks-old) were equally assigned to two dietary treatments. While the diet of the control group did not contain phytogenic feed additives, the Anta^®Ox group received a diet with 150 g/ton Anta^®Ox FlavoSyn (Dr. Eckel Animal Nutrition GmbH & Co. KG). Each group had three replicates (10 hens). Breeders were kept from 47 to 62 weeks of age to determine the effect of Anta^®Ox FlavoSyn on egg quality, productive performance and reproductive performance.

During the experimental period 16 h/day of manipulated lighting and ventilation at a natural ambient temperature were applied.

The basal diet mainly was formulated according to NRC recommendations (1994) and consisted mainly of corn (64.0 %) and soybean meal (22.5 %).

Productivity performance: Productivity of hens was recorded by determining feed intake (g/d), laying rate (%), egg number/hen, egg mass/hen and FCR. Feed intake of each replicate was recorded every 28 days.

Reproductive performance: Reproductive performance was evaluated by calculating the fertility and hatchability of eggs and the hatchability of fertile eggs (%).

Egg quality: The egg quality was investigated by measuring the total anti-oxidative capacity of the eggs (mM/L).

RESULTS AND DISCUSSION

Results showed that Anta^®Ox FlavoSyn had no effects on feed intake (g/hen), ranging at 109 g/day in both groups. This result contradicts findings by other authors that anti-oxidative, anti-inflammatory plant compounds may lower feed intake (Moon et al., 2007). Although feed-intake was not higher in the Anta^®Ox group, all other performance parameters of the breeder hens were significantly improved. In agreement with egg mass enhancing effects, Kara et al. (2016) observed that grape pomace significantly increased egg mass in laying hens. Furthermore, in their study liver weight was increased by feeding grape pomace. This might have led to increased metabolic capacities and higher egg mass. However, effects of pure grape pomace on feed efficiency and egg production were not significant, likely because of the low polyphenolic content of the tested grape pomace (Kara et al., 2016).

In contrast, results shown in Table 1 confirmed that Anta^®Ox FlavoSyn enhanced laying rate and number of eggs per hen by 6.8 and 6.9 % respectively.

While feeding of pure hops in much higher dosage (907 g/t) to broilers resulted in an improvement of FCR by 5.3 % (Cornelison et al., 2006), feeding Anta^® Ox FlavoSyn improved the FCR by 8.5 % (Table 1).

Furthermore, fertility was increased by 1.5 % when feeding Anta^®Ox FlavoSyn. In more detail, hatchability of set and fertile eggs were increased by 4.3 and 2.7 % (Fig. 1).

The fertility increasing effects of Anta^®Ox FlavoSyn that we observed in the study might be related to the higher anti-oxidative capacity of eggs during the experiment (Fig. 2). In agreement, Radwan et al. (2008) observed that plant compounds had positive effects on the oxidative stability and hatchability of eggs. However, the required dosage of the tested plant compounds was 66 times higher than the dosage of Anta^®Ox FlavoSyn. The increased anti-oxidative capacity may also have positive effects on the storage stability of the eggs. In summary results indicate that feeding Anta^®Ox FlavoSyn is more effective than single plant compounds tested by Cornelison et al. (2006), Kara et al. (2016) and Radwan et al. (2008). The better efficiency of Anta^®Ox FlavoSyn is likely related to its high flavonoid content and the synergistic combination of different flavonoid-sources.

Table 1 Anta^®Ox FlavoSyn enhances performance and FCR in breeder hens

CONCLUSIONS

Supplementation of Anta^®Ox FlavoSyn can be used to maximize the egg production performance, fertility and quality of egg yolk in older breeder hens. Results confirm that feeding Anta^®Ox FlavoSyn is more effective than single plant components. Positive effects on performance and egg quality can be expected not only in local but also in high yielding breeds and may be used to improve profitability and storage stability of eggs in laying hens.

References on request