Genetic parameters for test-day milk yield, 305-day milk yield, and lactation length in Guzerat cows

Milk production in tropical environments requires the use of crossbreeding systems including breeds well adapted to harsh conditions, but with lower productivities when compared to specialized breeds. Besides the genetic improvement for milk production, lactation lengths also need to be studied for most of these breeds. Accordingly, genetic parameters were estimated for 305-day cumulative milk yield (MY305), test-day milk yield (TDMY), and lactation length (LL) using information from the first lactations of 2816 Guzerat cows selected for milk production in 28 herds in Brazil. Contemporary groups were defined as herd, year and season of the test for TDMY, and as herd, year and season of calving for MY305 and LL. Variance components were estimated with the restricted maximum likelihood method under a multi-trait animal model. Heritabilities estimated for TDMY ranged from 0.16 to 0.24, and were 0.24 and 0.12 for MY305 and LL, respectively. Genetic correlations were high and positive, ranging from 0.51 to 0.99 among TDMY records, from 0.81 to 0.98 between each TDMY and MY305, and from 0.71 to 0.94 between each TDMY and LL. Genetic parameters obtained in this study indicated the possibility of using test-day records for the prediction of breeding values for milk yield in this population of the Guzerat breed. The use of TDMY as selection criteria would result in indirect gains in MY305 and LL. However, the highest response to selection for MY305 would be obtained by direct selection for this trait. © 2012 Elsevier B.V.

Jornal da UNESP, 2014, ano XXVIII, n. 305

Jornal elaborado pela Assessoria de Comunicação e Imprensa da Reitoria da UNESP

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 305 - Mitteilung an den Professor Hugo von Meltzl über seinen Umzug von Port-au-Prince nach Berlin

u.a.: Pensionierung; Verhandlung mit dem Stuttgarter Verlag W. Spemann wegen der geplanten Veröffentlichung zu Baron Münchhausen; Absatz des bei Brockhaus erschienenen Publikation des Schopenhauer-Nachlasses; Eduard Grisebach; W. Spemann;

Ms.Ff.F.Stoltze 3. 305 - Brief von Leopold Sonnemann an Friedrich Stoltze

Karl Müller, Victoriatheater, Rom, Italien

Inc. oct. 305 - Doctrinale. P. 1.

Vorbesitzer: Dominikanerkloster Frankfurt am Main;

Nicole Loraux. Las experiencias de Tiresias. Lo femenino y el hombre griego. Buenos Aires, Biblos, 2003, 305 pp.

Fil: Alonso, Griselda Esther.

Francisco Caudet. Zola, Galdós, Clarín. El naturalismo en Francia y en España. Madrid, Ediciones de la Universidad Autónoma de Madrid, 1995, 305 págs.

Fil: Macciuci, Raquel. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Francisco Caudet. Zola, Galdós, Clarín. El naturalismo en Francia y en España. Madrid, Ediciones de la Universidad Autónoma de Madrid, 1995, 305 págs.

Fil: Macciuci, Raquel. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.