Heavy broilers exposed to hot summer conditions experience fluctuations in surface temperatures due to heat stress, which leads to decreased performance. Maintaining a bird’s homeostasis depends on several environmental factors (temperature, relative humidity, and air velocity). It is important to understand the responses of birds to environmental factors and the amount of heat loss to the surrounding environment to create thermal comfort for the heavy broilers for improved performances and welfare. This study investigates the variation in surface temperatures of heavy broilers under high and low air velocity treatments. Daytime, age and bird location’s effect on the surface temperature variation was also examined. The experiment was carried out in the poultry engineering laboratory of North Carolina State University during summers of 2017, 2018, and 2019 as a part of a comprehensive study on the effectiveness of wind chill application to mitigate heat stress on heavy broilers. This live broiler heat stress experiment was conducted under two dynamic air velocity treatments (high and low) with three chambers per treatment and 44 birds per chamber. Surface temperatures of the birds were recorded periodically through the experimental treatment cycles (flocks, 35–61 days) with infrared thermography in the morning, noon, evening, and nighttime. The overall mean surface temperature of the broilers under two treatments was found to be 35.89 ± 2.37 °C. The variation in surface temperature happened due to air temperature, thermal index, air velocity, bird’s age, daytime, and position of birds inside the experimental chambers. The surface temperatures were found lower under high air velocity treatment and higher under low air velocity treatment. During the afternoon time, the broilers’ surface temperatures were higher than other times of the day. It was also found that the birds’ surface temperature increased with age and temperature humidity indices. Based upon the experimental data of five flocks, a simple linear regression model was developed to predict surface temperature from the birds’ age, thermal indices, and air velocity. It will help assess heavy broilers’ thermal comfort under heat stress, which is essential to provide a comfortable environment for them.

The broad impact of the removal of all institutional barriers to the production and movement of fluid milk on the dairy industry of the Northeastern and North Central regions is examined. Competitive equilibrium patterns of milk production, utilization, prices, and shipments are obtained by estimating supply and demand functions for various areas of the nation and relating prices in the areas by transfer costs for fluid and manufactured milk. The effects of alternative estimates of some key variables are studied. All equilibrium solutions show a decline in Class I prices in the Northeast, a general increase in manufacturing milk prices, and some shift of production from the Northeast to the Lake States. These results are modified only a little by introducing a hypothetical fresh milk concentrate. Some implications for price policy are discussed.M ILK MARKETING is characterized by a large degree of geographic variation in production, consumption, disposition, and prices. Observation suggests that relationships among prices and production in different areas and of different products often are far from competitive equilibrium. For example, a large and increasing percentage of the fluid-eligible milk sold in several markets is actually used in manufactured milk products. In addition, some price differentials within and between regions appear to exceed transfer costs by appreciable amounts.Several institutional factors associated with fluid milk marketing are often cited as causing these distortions by acting as barriers to the movement of milk among geographic areas. These institutional factors include sanitary and trucking regulations and various pricing penalties. Strong producer cooperatives then succeed in using the classified pricing system and market orders to exploit the relatively inelastic demand for fluid milk, raising the returns to local producers, With blend pricing and no production control, producers then provide more milk of fluid quality than required for fluid needs.Such institutional arrangements are under considerable pressure because of surplus milk production and technological changes in dairy ,0 Journal Series No. 2905 of The Pennsylvania Agr. Expt. Sta. The article necessarily omits a great deal of detail about supply and demand functions, transfer costs and area solutions. Such details are given in D. A.