Variation in the estimates of domiciled cats and dogs population size in the city of São Paulo

• Grant number: 18/20707-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2018
• End date: November 30, 2019
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Oswaldo Santos Baquero
• Grantee: Dafne Fontoura de Lima
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Estimates of pet population size serve to design, evaluate and monitor actions of population management and disease control. These actions are beneficial to human and animal health. In 2008, the estimates of the cat and dog population sizes in São Paulo were 2.507.401and 562.965, respectively. In 2015, these estimates were 1.874.601 e 810.170, respectively. The magnitude of the difference between estimates of 2008 and 2015 represent a drastic demographic change, which demands a reallocation of efforts for control and prevention diseases, and for population management. However, we should consider that the methods used to estimate population sizes are prone to introduce biases, and these biases can lead to wrong conclusions and interventions. The main objective of the present study is to explain the possible reasons why there is a discrepancy between the estimates of 2008 and 2015, evaluating both the possibility of bias in one of the studies, and the plausibility of such a drastic demographic change. To this end, the 2008 estimates will be analyzed according to the consistency between the published results and the census data provided by IBGE and used in the research. The data from 2015 estimates are available and will be used to recalculate the estimates and their confidence intervals. The 2015 data will be used to calculate parameters other than the population size, and to construct population pyramids conditioned by sex, age and reproductive status. The discussion of the results will be supplemented by considering the demographic possibility of the differences that were found, taking the year of data collection and the study population into account.