Animals inheriting the slick hair gene have a short, sleek, and sometimes glossy coat. The objective of the present study was to determine whether slick-haired Holstein cows regulate body temperature more effectively than wild-type Holstein cows when exposed to an acute increase in heat stress. Lactating slick cows (n = 10) and wild-type cows (n = 10) were placed for 10 h in an indoor environment with a solid roof, fans, and evaporative cooling or in an outdoor environment with shade cloth and no fans or evaporative cooling. Cows were exposed to both environments in a single reversal design. Vaginal temperature, respiration rate, surface temperature, and sweating rate were measured at 1200, 1500, 1800, and 2100 h (replicate 1) or 1200 and 1500 h (replicate 2), and blood samples were collected for plasma cortisol concentration. Cows in the outdoor environment had higher vaginal and surface temperatures, respiration rates, and sweating rates than cows in the indoor environment. In both environments, slick-haired cows had lower vaginal temperatures (indoor: 39.0 vs. 39.4 degrees C; outdoor 39.6 vs. 40.2 degrees C; SEM = 0.07) and respiration rate (indoor: 67 vs. 79 breaths/ min; outdoor 97 vs. 107 breaths/min; SEM = 5.5) than wild-type cows and greater sweating rates in unclipped areas of skin (indoor: 57 vs. 43 g x h(-1)/m(2); outdoor 82 vs. 61 g x h(-1)/m(2); SEM = 8). Clipping the hair at the site of sweating measurement eliminated the difference between slick-haired and wild-type cows. Results indicate that slick-haired Holstein cows can regulate body temperature more effectively than wild-type cows during heat stress. One reason slick-haired animals are better able to regulate body temperature is increased sweating rate.

The aim of this study was to compare egg production performance and welfare traits of laying hens kept in conventional cage (CC), enriched cage (EC), and free range (FR). Lohmann Brown laying hens (n = 480 with 160 per housing type) were studied across a production cycle from placement at 17 wk until depopulation at 66 wk. The hens were randomly allocated into cages or pens of housing system groups; within each system there were four replicates with 40 hens in each pen or cage. The hen day egg production (P = 0.037), feed intake (FI) (P < 0.001), egg mass (EM) (P < 0.001), and dirty egg ratio of hens were higher in the FR system but similar in the CC and EC systems. The highest mortality ratio was found in EC system hens (P = 0.020). The best feather score was found in FR system hens (P < 0.001). The worse body wound score was found in EC system hens (P = 0.038). On the other hand, the worse bumble foot and footpad lesions were found in FR system hens (P < 0.001). The highest tibia breaking strength was found in FR system hens compared with in CC and EC system hens (P < 0.001). The highest Heterophil/Lymphocyte ( H/L: ) ratio was found in CC system hens (P = 0.006) but the blood phosphorus ( P: ) level was higher in FR system hens (P = 0.013). The tonic immobility, blood glucose, total cholesterol, triglyceride, and Ca values of hens were found to be similar in all systems (P > 0.05). The hens in the FR system had additional space for optimum comfort and better feather and bone traits, but the dirty egg ratio, feed consumption, and foot lesions were higher than in CC and EC systems.

The material for the current research was obtained from 480 layers (Lohmann Brown) housed in conventional-cage (CC), enriched-cage (EC), and free-range (FR) production systems between 22 and 60 weeks of age. A total of 720 eggs were analyzed for external and internal egg quality traits.The three housing systems were located within the same research unit of Uludağ University. Two cage systems, CC and EC, were installed in a windowed and fan-ventilated cage hen house with both cage types in the same room. The FR system was located 120 m from the cage hen house.The CC system consisted of galvanized wire cages (50 × 45 × 45 cm) with a trough-type galvanized feeder, egg belt, manure belt, and nipple drinker. Each CC cage provided a total of 562.5 cm 2 floor area per hen.The EC system cages met the requirements of EU Directive 1999/74/EC. The EC system consisted of 2 tiers, and each tier consisted of 2 cages (4 EC cages). The EC

1. The research was carried out to investigate correlations between breeder age, egg cholesterol content, blood cholesterol level and hatchability of broiler breeders. 2. Egg cholesterol content increased with increased breeder age. The mean yolk cholesterol contents (mg per g yolk) were 10.47+/-0.28, 15.34+/-0.65 and 15.64+/-0.71 mg/g at 28, 45 and 65 weeks of age, respectively. 3. There were positive correlations between yolk weight and yolk cholesterol content (mg/g yolk) (r=01.941; P<0.01) and egg cholesterol content (mg/egg) (r=0.980; P<0.01). 4. Negative correlations were found between egg yolk cholesterol content and hatchability of fertile eggs (r=-0.345; P<0.05), fertility ratio (r=-0.609; P<0.01) and hatchability of total eggs (r=-0.574; P<0.01). 5. The mean blood cholesterol levels were 165.1+/-11.04, 166.5+/-11.97 and 179.5+/-11.33 mg/dl at 28, 45 and 65 weeks of age, respectively.

The aim of study was to determine the relationships between morphological characteristics of roosters and fertility in broiler breeders at different age periods. A total of 48 roosters and 480 hens Ross 308 broiler breeder were used. The body weight, comb width and length, wattle width and length, and tarsus length of roosters were measured for morphological characteristics at 42, and 53 weeks of age. A total of 1500 eggs were incubated at 37.7 °C and 50-55% relative humidity for 18 d, then eggs were incubated at 36.6 °C and 60% relative humidity for 3 d. The effect of age on comb length, comb index (P=0.002), wattle width (P=0.008), wattle area (P=0.015) and tarsus length were found significant (P=0.000). There were correlations between body weight and fertility at 53 weeks of age (r = 0.663; P&lt;0.05). There was no correlation between fertility and comb length, comb width, comb area, comb index, wattle width, wattle area, wattle index, and tarsus length at 42 and 53 weeks of age (P&gt;0.05). In conclusion; some characteristics based on external appearance are used for male selection in broiler breeders, but no relationship was found between investigated morphological characteristics and fertility, except for body weight.