Contribution to the study of hematology of Nelore calves produced by somatic cell nuclear transfer

Author(s)

Eliza Rossi Komninou

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2008-08-22

Examining board members

Eduardo Harry Birgel Junior; Fernando José Benesi; Flávio Vieira Meirelles

• Advisor: Eduardo Harry Birgel Junior

Abstract

The present work aimed to study the hematology of cloned Nelore calves produced using the technique of somatic cell nuclear transfer (SCNT), by evaluating erythrocyte parameters, hemoglobin dynamics, and iron metabolism in the animals during the first month after birth. The experimental design included the collection of 260 blood and blood serum samples from 20 calves in the following times: immediately after birth, 12 hours after birth, 1st of life, 2nd, 3rd, 4th, 5th, 7th, 20th and 30th day of life. The animals were classified in four experimental groups: 12 calves produced, using SCNT for two commercial laboratories (laboratory A=5 calves and laboratory B= 7 calves), four calves produced by in vitro fertilization (IVF) and four calves produced by natural mating (NM). Mild to severe normocytic and normochromic anemia was observed in 100% (5/5) cloned calves from laboratory A, and 14.2% (117) cloned calves from laboratory B. In both IVF and NM calves, anemia was observed in 50% (214) of the calves. Erytrogram evaluation of cloned calves from laboratory A showed that anemia developed gradually from 12 hours after birth, was most intense at the end of the first week, and then erytrogram normal values were recovered after the 15th day of life. Mean values for the laboratory A cloned calves erytrogram in the 7th day of life were the following: Red cells 4033X106/mm3, hematocrit 23%, hemoglobin 7.25g/dL, MCV 52.89µ3-; MCH 16.65, MCHC 31.47%. Anemia observed in cloned calves from laboratory A was caused by iron deficiency, since a significant decrease in iron se rum levels together with a decrease in transferrin saturation index (TSI) was confirmed. At the same time, Total iron-binding capacity (TIBC) was not changed in this period of time. Mean iron metabolism values for cloned calves from laboratory A were the following: serum iron amount: 47,35mg/dL, TIBC 455,90 mg/dL and TSI 9,64%. Hemoglobin identification by eletrophoresis identified three adult hemolglobin phenotypes (A-Hb; B-Hb e AB-Hb) and the fetal hemoglobin (F-HB), and there was no sign of hereditary hemoglobin disorders were observed. The rate of A-Hb in cloned calves with A-Hb and AB-Hb phenotypes was maintained during the experimental period. Nonetheless, for the IVF calves with the same phenotypes (A-Hb and AB-Hb) a constant increase in the A-Hb was noticed. For the evaluation of F-Hb dynamics in the first month of life, results showed similar pattern, characterized by its decrease with age. (AU)