Copyright is owned by the Author of the thesis. Permission is given for a copy to be downloaded by an individual for the purpose of research and private study only. The thesis may not be reproduced elsewhere without the permission of the Author. --_ .. _-- STUDIES OF HOLSTEIN-FRIESIAN CATTLE BRED FOR HEAVY OR LIGHT MATURE LIVE WEIGHT Jose G. Garcia-Muiiiz 1998 Studies of Holstein-Friesian Cattle Bred for Heavy or Light Mature Live Weight A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy Institute of Veterinary, Animal and Biomedical Sciences Massey University Jose G. Garcia-Mufiiz 1998 MASSEY UNIVERSITY LffiRARY THESIS COPYRIGHT FORM Title of Thesis: shLs Please delete section not applicable. (1) I give permission for my thesis to be made available to readers in Massey University Library under conditions determined by the Librarian. (b) I do not wish my thesis to be made available to readers without my written (2) (b) (3) Q (b) consent for months. I agree that my thesis, or a copy, may be sent to another institution under conditions determined by the Librarian. I do not wish my thesis, or a copy, to be sent to another institution without my written consent for _ months. I agree that my thesis may be copied for Library use. I do not wish my thesis to be copied for Library months. Signed: Date: ****************************************************************************** The copyright of this thesis belongs to the author. Readers must sign their name in the space below to show that they recognise this. They are asked to add their permanent address. NAME and ADDRESS DATE TO WHOM IT MAY CONCERN This is to state the research carried out for the PhD thesis entitled: "Studies of Holstein-Friesian cattle bred/or heavy or light mature liveweighf' was done by Jose G. Garcia-Mufiiz in the Animal Science Department, Massey University, Palmerston North, New Zealand. The thesis material has not been used for any other degree. Chief Supervisor =� ,JJ MASSEV UNIVERSITY Private Bag 11222 Palmerston North New Zealand Telephone +64-6-356 � Facsimile +64-6-350571 COLLEGE OF SCIENCES - INSTITUTE OF VETERINARY. ANIMAL & BIOMEDICAL SCIENCES TO WHOM IT MAY CONCERN This is to state the research carried out for the PhD thesis entitled: "Studies of Holstein-Friesian cattle bred for heavy or light mature liveweighf' in the Animal Science Department, Massey University, Palmerston North, New Zealand is all my own work. This is also to certify that the thesis material has not been used fOF any other degree. Date: =� �I� �\\�'J MASSEV UNIVERSITV Private Bag 11222 Palme�ston North New Zealand Telephone +64-6-356 909 Facsimile +64-6-350571 COLLEGE OF SCIENCES - INSfITUTE OF VETERINARY. ANIMAL & BIOMEDICAL SCIENCES Dedication I dedicate this Thesis to my wife Marcela and my children Jose Alberto (5), Ana Victoria (4) and Eduardo ( 1 ). For all their love and support, and for putting up with my busy schedule during the first three years of my PhD and with my absence during the last 1 0 months. To my mother, Victoria Muiiiz, for encouraging me to further my education since the very first day I attended primary school. Abstract The new Animal Evaluation Model predicts that heavier live weight (LW) of the lactating cow reduces the profitability of the pasture-based dairying farm in New Zealand, because its effects on increased maintenance requirements are not fully compensated by the extra income generated from selling heavier culled cattle and surplus progeny. The work outlined in this thesis was intended to validate the expected effects of selection for differences in LW on actual LW from birth to maturity and on herbage 'intake and feed conversion efficiency (FCE) of growing cattle and lactating cows. It also investigated the existence of any associated effects on calving difficulty, calf mortality, onset of puberty and reproductive performance of the two lines of Holstein-Friesian (HF) cattle bred for heavy or light mature LW. These two lines have been developed at the Dairy Cattle Research Unit, Massey University, New Zealand, since 1989. The high genetic merit HF cows from the base herd have been mated to high genetic merit HF sires with either high or low breeding value (BY) for LW but with similar breeding worth (BW) in order to generate the heavy (H) and the light (L) mature LW selection lines. During the period 1994 to 1997, a series of experiments with growing heifers and lactating cows from the H and L lines, and analysis of data collected from the cows were undertaken to compare the two genetic lines. The BY's for live weight of the sires were 86 kg for the H and 31 kg for the L cows and the actual H animals were heavier at birth (41 vs. 35 kg) and at maturity (510 vs. 460 kg). In addition the BY's for milk (1037 vs. 737 f), milkfat (33.0 vs. 27.5 kg) and milk protein (31 kg vs. 22 kg) of H sires were also higher and the H cows produced significantly more milk (4708 vs. 4323 //lactation), more milkfat (207 vs. 198 kg/lactation) and more milk protein (157 vs. 150 kg/lactation) than the L cows. However, the L sires had slightly higher breeding worth ($ 46 vs. $ 37) than the H sires and theoretically calculated and experimentally measured feed intakes and the resultant feed conversion efficiencies, confirmed that the L cows had slightly higher values for FCE than the H cows in three short-term grazing experiments and when FCE was calculated over multiple lactations. Therefore the basic assumptions in the Animal Evaluation Model seem to be correct. Sires of H cows had a higher proportion of USA Holstein genes in their pedigrees than the L sires. Consequently cows from the H line had a higher (�27%) proportion of USA Holstein genes compared to cows from the L line (�7%), whose sires were mainly of New Zealand ancestry. New Zealand bulls are progeny tested under grazing conditions and a very tight seasonal system of reproduction, whereas North American bulls are progeny tested under dairying systems of all year round milk production and feedlot feeding. II There were significant differences in the pattern of grazing behaviour of H and L cows. The L cows displayed a more 'aggressive' pattern of grazing behaviour than H cows given by significantly longer grazing times (520 vs. 499 min/d), faster rates of biting (58 vs. 52 bites/min), higher number of total bites per day (31053 vs. 25046 bites/d), lower rumination times (471 vs. 572 min/d), and the selection of herbage of higher digestibility (72.0% vs. 69.3%). These results may reflect not only a difference in mature LW between the H and L cows, but may also reflect a strain of Holstein (i.e. NZ vs. USA Holstein) difference due to the sires' ancestry referred to above. There were no differences between H and L cows in the incidence of calving difficulty. However, offspring of bulls with high BY for rump width (i.e. wider pelvises) were more likely to face a difficult calving, and so were daughters of bulls with low BY for rump angle (i.e. less sloping pelvises). There were no differences between H and L cows for calf mortality. However, induced calves were more likely to die or undertake an emergency slaughter, and the H cows had significantly higher induction rates than the L cows (10.5 vs. 4.2%). The H heifers grew faster, ate more feed (4.3 vs. 3.8 kg/hd/d) and were heavier (241 vs. 221 kg) and older (325 vs. 300 d) at puberty than L heifers, and there were no differences between H and L heifers in pregnancy rate, age at first calving and first lactation yield of milk and milk components. There were only small differences in the reproductive performance of H and L cows after adjusting by differences in induction, calving date and percentage of USA Holstein genes in the cows. The L cows had si ightly shorter intervals from first service to conception (13 vs. 17 d) and from the start of mating to conception (24 vs. 29 d), and slightly higher first service conception rate (65 vs. 54%), which translated in a more concentrated calving pattern and lower induction rate (4.2 vs. 10.5%) for the L cows. The results of this thesis indicate that selecting for heavier mature live weight produced the expected results of heavier animals with higher yields of milk and milk components, higher feed requirements and higher herbage intakes and slightly lower feed conversion efficiency than lighter mature live weight cows. However, there were also differences in grazing behaviour in which the L cows displayed a more competitive pattern of grazing behaviour than the H cows. The results of this thesis suggest that for the New Zealand seasonal system of milk production based almost completely on grazed pasture, lighter mature LW HF cows may have an advantage over heavier mature LW cows. Under the conditions of this experiments L cows were slightly more efficient, younger at puberty, had a more concentrated calving pattern, and were less prone to be induced to calve than heavier mature live weight HF cows. III Acknowledgements A project of this magnitude could not have been completed without the help, input, participation, enthusiasm and foresight of many people. Back in 1987 Associate Professor Colin Holmes from Massey University and Dr. Brian Wickham and Gisele Ahlborn-Brier from the Livestock Improvement Corporation laid the foundations of the present project. I am particularly grateful to Associate Professor Colin Holmes for giving me the opportunity to study under his supervision. The promptness of reviewing research proposals, ideas, and all the chapters making up this thesis is highly appreciated. I am particularly appreciative of his interest in the development of my Ph.D. program, and the unlimited and unrestricted time he has devoted to helping me during the time I have been under his supervision. I have benefited immensely from his enjoyable style of supervising, which has provided a model I will try to emulate with students under my care in the future. I am grateful to his wife, Dorothy Holmes, for making me feel at home and for trusting me not only with her house but also her 'precious' cats while they were on holiday. Dr. Ian Brookes, Dr. Gavin Wilson, Professor Dorian Garrick, Dr. Duncan Mackenzie, Associate Professor Roger Purchas and Professor John Hodgson provided valuable feedback to improve this thesis. During two years Yvette Cottam helped me with the collection of blood samples and field data while the heifers were grazing away. The weekly trips we made to collect the data were a delightful experience. During the winter months we were able to taste most of the local chocolate brands available, while in summer we always made sure to call into a Fielding Pub for a bowl of hot 'Nachos' and a cold beer. I am grateful to Jeff Purchas for his invaluable help in the running of the experiments and skilful handling of the animals. My especial appreciation to Martin L. Chesterfield, manager of the research herd, for his help and strategic support during the running of the experiments. A great lesson I learned from Martin was that a research farm could still be in the top 10% of the high profit farms within the district. The secret: how to accommodate the needs of both the cows and the researchers within the constraints of the dairy farm. A large number of international students gave their time to participate in the running of the experiments and collection of field data. In no particular order, I will always be grateful to Stuart Crosthwaite (Australia), Lisa Watson (New Zealand), Michelle Jones (Canada), Jan (Holland), Brian Read (U.K), Carolina Realini, Daniel Laborde and Bettina (Uruguay), Pablo Londofio (Colombia), and from Mexico, Nicolas L6pez, David Pacheco, Aurelio Guevara, Mauricio Padilla and Alberto Torres. iv My fellow post-grads Nicoilis Lopez (Mexico), Richard Spelman (NZ) and Paul Charteris (NZ) provided valuable discussions and were always willing to review and comment on early drafts making up the chapters of this thesis. I am grateful they accepted helping me with this early 'peer review'. I am particularly grateful to my friend and colleague, Nicol