Spei Domus

1-13

Authors: Nidia Fernanda Gamboa-González, Ariel Leonardo Cotamo-López, Nixon Ali Suárez-Gómez

The genetic improvement programs in broilers are updated based on parameters of interest such as zootech-nical performance, yield and quality of the carcass, as well as economic viability. Therefore, the development of new genetic lines that respond positively to the productive challenges of the industry is one of the biggest challenges found today. The objective of this work was to evaluate the zootechnical performance and degree of feathering of the birds during their productive cycle. There were used 2400 male and female broilers, distributed in randomized blocks in a 2 x 2 factorial system (Sex x Line), being two sexes and two genetic lines (line A x Line B) with 12 repetitions per treatment. The birds were distributed in 48 corrals of 2.25 x 1.50 with an initial occupation of 50 birds per corral (14.8 birds/m2), the feeding and lighting program was established by the company. Zootechnical performance parameters were evaluated weekly and the feathering degree on day 41. The data were analyzed by the statistical test of T student and U Mann Whitney’s in data that did not have normal distribution, using the IMB program SPSS 25. No significant differences were observed between the genetic lines evaluated for the variables of body weight, feed consumption, feed conversion, weight gain and efficiency at day 41 of age. With respect to the degree of feathering, the females of the B line presented a greater degree of feathering than the other treatments.

1-22

Authors: Alcides Zabala Mendoza, Héctor Jairo Correa Cardona, Ángel Giraldo Mejía

Introduction: Carnitine is key in the proper metabolism of lipids, so its deficiency can trigger metabolic and productive problems during peripartum, for this reason, the objective of this study is evaluated the parenteral application of various doses of L-carnitine to cows during the peripartum; Methodology: Each treatment consisted of six Holstein cows between second and sixth birth to Holstein cows of high production, grazing kikuyu grass (Cenchrus clandestinus [Hochst. ex Chiov.] Morrone) and supplemen-ted with a concentrate food 0, 5, 10 and 15 grams of L-carnitine in solution were applied via intramuscular every 5 days from day 270 of gestation to day 15 postpartum on dry matter intake (DMI), energy balance (EB), milk was estimated using the indicator technique. MY, MF and MP were measured on days 5, 10, 15 and 20 of lactation. On day 270 of gestation and on days 10 and 20 postpartum the EB of each cow was calculated. Results: The results of these measurements are analyzed in a time-divided plot design. Conclusions:The treatments do not affect DMI, MY, MP, MF and EB (p> 0.05), under the experimental conditions described in this work, parenteral L-carnitine has no effect on milk production, composition and EB