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Professor

Ph.D. - Universidad de Córdoba, Spain, 1994

Phone: 301-405-5779
Email: iestevez@umd.edu
Website: Poultry Behavior & Welfare

Research Interests:

The goal of my research is to identify new management practices and environmental designs that promote health, welfare and growth in poultry, but that can also be applied to other domesticated or wild species kept under confinement. My laboratory has a particular emphasis in broiler research. My research projects range from the study of the dynamics of social behavior, spatial distribution, animal-environment interactions and environmental enrichment, to reproductive behavior and sexual selection theory. Most of these studies are based in principles of Behavioral Ecology theory and adjusted to the specific captive environmental conditions.

As examples of my research, currently my team is studying fundamental behavioral and morphological causes of reduced fertility in broiler breeders with the following objectives: 1) To quantify the impact of social dominance on male broiler breeder fertility, 2) To determine the impact of male social status on semen quality and functionality and 3) To investigate the use of morphometric and behavioral traits as reliable indicators of high male fertility that can be incorporated into genetic selection protocols to improve flock fertility. This project applies concepts from behavioral theory (such as sperm competition or mate guarding) to the improvement of fertility in poultry. Other examples of my work include the determination of how social and physical factors (associated with increments in group size and density respectively), or distribution of resources (such as food and cover availability) affects the behavior and use of space of broiler chickens. We are also investigating the use of new techniques, such as fluctuating asymmetry and neural network analysis, as potential reliable measures of fitness and welfare in poultry, and establishing new statistical methodologies for spatial analysis of animals in confinement.

The results of all these investigations will give us a better understanding of the interactions between the bird and its environment and will enable us to develop new technologies to resolve practical management problems from a behavioral stand point and to improve both broiler health, and welfare while maximizing performance (see Figures a & b for an example).

Figure. a) Litter area in a problematic broiler breeder flock, and b) the same flock 24 hours after introducing the spatial partitions. Note the increased number of females present in b). This technique reduces male aggression over females and potentially increases fertility. Patent: # US 6,289,848, B1

Awards and Honors:

- National award in Ethology, Gonzálo Nardiz years 1991 & 1993, Agriculture and Fisheries Branch of the Basque Government, for the works entitled: Comportamiento del muflón (Ovis orientalis musimon) durante la época reproductora. [The behavior of muflon (Ovis orientalis musimon) during the rut]. And for 1993: El sistema de organización social en pollos broilers: Una nueva perspectiva. [The social system in broiler chickens (Gallus gallus): A new perspective].
- July 1994-March 1995: Post-doctoral Fellow of the Swedish Institute, Agricultural University, Skara, Sweden. Visiting fellowship.
- April-Sept 1995: Post-doctoral Fellow of the Institute National de la Recherche Agronomique (INRA), Tours, France. Visiting fellowship.
- 2002: College of Agriculture and Natural Resources Junior Faculty Award, University of Maryland, College Park.
- 2003: Poultry Science Association, Hy-line International Research Award (Junior Faculty Research Award).