Efectos de horas luz sobre niveles sanguíneos y órganos linfoides en pollos de engorde

This study evaluated the effect of different photoperiods (20, 18, and 16 hours of daily light) on hematological parameters, body weight, and lymphoid organs in 28-day-old broiler chickens. Birds were distributed into three treatments (T1 = 20 h, T2 = 18 h, T3 = 16 h of light) under a completely randomized design. Hematological parameters were analyzed using both parametric and non-parametric tests, and absolute and relative weights of the spleen, thymus, and bursa of Fabricius were assessed. The results indicated that T1 presented the highest values for hematocrit (35.17%), hemoglobin (11.48 g/dL), red blood cells (2.5x10⁶/μL), and thymus weight, suggesting a positive stimulation of erythropoiesis and immunological development under prolonged photoperiods. In contrast, group T3 recorded the highest body weight, although it showed a lower morphometric conversion index of the thymus, suggesting a possible compromise of immunity in favor of organ growth. No significant differences were observed in spleen weight or differential leukocyte counts among treatments. It is concluded that a photoperiod of 20 hours of light favors hematological and immunological development, while 16 hours of light stimulate body growth. These results highlight the importance of balancing the lighting regime to optimize both productive performance and immune competence in broiler chickens.

• Main Author: Moreira Chica, David Francisco (author)
• Other Authors: González Quiñonez, Tomás Gregorio (author)
• Format: bachelorThesis
• Language: spa
• Published: 2025
• Subjects: Pollos de engorde; Fotoperiodo; Hematología; Órganos linfoides
• Online Access: http://repositorio.espam.edu.ec/handle/42000/2764