The effect of serine protease on broiler growth and carcass quality

DOI: 10.15414/afz.2014.17.03.87–89Received 22. May 2014 ǀ Accepted 9. June 2014 ǀ Available online 27. August 2014The experiment was performed to compare the influence of commercial serine protease in broiler grower diets with standard crude protein (CP) and lower CP level on growth parameters and carcass quality. One thousand three hundred twenty 1-d-old Ross 308 broiler chicks of both sexes were randomly allocated into 4 dietary treatments each with three replicates (4x3x110). Diets with two levels of CP (21.1 and 20.4%) with and without protease were used. At the end of the experiment 36 birds from each treatment were randomly chosen for carcass quality measurement. Results of the experiment showed that supplement of serine protease to the diets did not have (P>0.05) significant effect on growth performance, but in lower CP diets improved both final body weight (1837.8 g vs. 1854.9 g) and FCR (1800.7 g/kg vs. 1785.2 g/kg). The supplement of protease to the diet with lower CP had positive significant effect (P<0.05) on carcass yield (71.9 vs. 73.0%). Serine protease supplementation had positive but not significant effect mainly on live weight and FCR in the diets with lower CP level.Keywords: crude protein, chicken, carcass yield

Pouziti tepelne upraveneho repkoveho krmiva ve vyzive slepic.

Summary in EnglishAvailable from STL, Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi

Egg quality of gene reserve czech golden spotted hens

DOI: 10.15414/afz.2014.17.03.84–86Received 16. May 2014 ǀ Accepted 11. July 2014 ǀ Available online 27. August 2014In Czech Republic, there are two national poultry breeds, Czech Goose and Czech Golden Spotted Hen (CZH), which are under governmental project of gene reserves. In 2012 there were less than 220 CZH both males and females in this program. The aim of this study was to evaluate the egg quality of CZHs included in the project of gene reserves kept in International Poultry Testing in Ustrašice.Four flocks of CZHs of four different breeders’ origin were used in the observation. They fed the same diets and they were the same age. Eggs for measurement egg quality were collected each two months 30 per flock from December to January next year.The egg weight ranged from 57.0 to 58.0g (P>0.05).  The eggshell strength was relatively high, in all flock higher than 35N, and the differences among the flocks were no significant (P>0.05). Significantly darker eggshell color expressed as SCI was found in one flock in comparison with the others (P0.05). The weight of yolk was higher than 18g in all flocks. The yolk proportion was significantly (P<0.05) lower in one flock (31.2%) in comparison with the rest of flocks (from 32.2 to 32.9%).Although the egg production in Czech Golden Spotted hens is very unbalanced, the egg quality is very consistent. At feeding the same diets there were no significant difference among the flocks in majority of observed characteristics. Advantage of the eggs is high weight of yolk and consequently yolk proportion.Keywords: egg weight, eggshell color, yolk proportio

Trends in early life conditions of pigs and laying hens in order to prevent damaging behaviour: a GroupHouseNet update

Damaging behaviours in pigs and laying hens are among the most concerning current welfare issues. They are multifactorial in origin and difficult to stop once occurring. Prevention is crucial, and this is the focus of the COST Action project ‘GroupHouseNet’. In laying hens, feather pecking (FP) can best be prevented at the hatchery. The parental stock’s predisposition for FP can be assessed by epigenetic analysis, allowing careful stock selection. The fertilized eggs are then conventionally incubated in the dark, but studies show that light provision may reduce FP. Recent development of in-ovo sexing reduces chick handling, thus reducing stress. It further allows hatching with food and water provision, enabling on-farm hatching. Accessing feed right after hatching can be crucial for chicks to learn what to peck and eat. Artificial dark brooders, mimicking the mother hen’s wings, reduce fear, stress and FP. Matching the rearing and laying system through an all-in-all-out system reduces stress by eliminating catching, handling, transport and changing environment. In practice, multiple all-in-all-out barns can provide continuous egg output. A sustainable and circular system of feeding chickens insects grown using chicken manure seems feasible and positive in preventing FP. The use of pasture and supplementing hens whole grains are also being researched as potential strategies. Together, these trends can help in preventing damaging FP in laying hens. For pigs, early life factors can also influence later damaging behaviour, such as aggression, tail and ear biting. Aggressive biting is mainly reduced by socialisation (i.e. co-mingling) before weaning. Here, piglets learn to establish dominance relationships early in life which reduces fight duration when older. Tail biting, which is largely unrelated to aggression, is increased by early life undernutrition, social stress due to competition and cross-fostering. These factors are all influenced by litter size at birth. Familiar odours may contribute to reducing biting when pigs are moved from one environment to another by alleviating the level of stress associated with novelty. Tail and ear injuries pre-weaning may also occur due to mycotoxins from feed or straw, and can result in the affected piglet being bitten and the development of biters. Paying attention to tail and ear injuries pre-weaning is therefore recommended. Even though the barren environment of the pigs represents the major risk for expression of damaging behaviour, the pre-weaning environment should be optimized to reduce the likelihood of this problem. Foraging possibilities are essential for both laying hens and pigs. Providing pigs and poultry with the requirements for expressing natural behaviour and for reducing stress is therefore necessary to prevent damaging behaviour