Source: PENNSYLVANIA STATE UNIVERSITY submitted to
GENETIC SELECTION AND CROSSBREEDING TO ENHANCE REPRODUCTION AND SURVIVAL OF DAIRY CATTLE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
NEW
Funding Source
Reporting Frequency
Annual
Accession No.
0216298
Grant No.
(N/A)
Project No.
PEN04287
Proposal No.
(N/A)
Multistate No.
S-1040
Program Code
(N/A)
Project Start Date
Oct 1, 2008
Project End Date
Sep 30, 2013
Grant Year
(N/A)
Project Director
Dechow, C. D.
Recipient Organization
PENNSYLVANIA STATE UNIVERSITY
208 MUELLER LABORATORY
UNIVERSITY PARK,PA 16802
Performing Department
Animal Science
Non Technical Summary
Over the past century, dairy cows have been largely bred and selected for milk production traits (milk yield, fat and protein content) and conformation. The application of genetic/selection tools to the US dairy population has resulted in tremendous genetic improvement in milk yield, an estimated change in genetic merit for milk production of 7,122 pounds per lactation in Holsteins from birth years 1957 through 2004. Genetic improvement has been responsible for over 50% of the total improvement observed in milk yield. However, emphases on selection and management for higher yields have negatively affected reproductive and survival traits of different breeds. Declines in fertility and survival induce higher costs for the already struggling dairy farmers and compromise cow welfare. The goal of this project is to enhance dairy cow survival and fertility through the following 4 objectives and expected outcomes: Objective 1: Develop selection tools to enhance reproduction and survival using field data. 1. Identification of genetically superior cows and bulls for female fertility through improved genetic evaluations of female fertility which include maternal influences on fertility. 2. Greater use of on-farm computer recorded data for assessment of genetic influences on health, reproduction, lifetime performance and survival. 3. Enhanced ability to select for lifetime performance due to improved genetic evaluations for it. 4. On-farm mortality rates established and genetic and environmental stressors leading to premature death identified. Objective 2: Evaluate the biological and economic impact of crossbreeding on lifetime performance of dairy cattle. 1. Enable dairy producers to strategically choose breeds and breed combinations to optimize the use of crossbreeding to maximize dairy performance. 2. Facilitate the use of crossbreeding to optimize lifetime performance of dairy cattle. Objective 3: Develop breeding goals and appropriate indexes for optimum biological and economic improvement of health, reproduction, survival, and production of dairy cattle. 1. Improve the economic efficiency of dairy production through selection on an improved lifetime net merit index based on an improved profit function. 2. Improved animal well-being enhanced by the ability to select for improved fertility, reproduction and health. 3. Enable dairy producers to make customized sire selection decisions through genetic rankings appropriate for different markets and production systems. Objective 4: Develop and recommend selection and crossbreeding protocols of optimum economic utility for adoption by US dairy farmers. 1. Provide optimum breeding systems which combine selection and crossbreeding and permit the formation of composite populations, if desired. 2. Production of the most economically efficient dairy cattle for commercial milk production through breeding strategies and mating systems. 3. Reduction of inbreeding and its consequences. 4.Provision of genetic options for graziers and organic producers. 5. Enhanced genetic evaluations which combine SNP genetic predictions and estimates of genetic merit from traditional field data.
Animal Health Component
60%
Research Effort Categories
Basic
20%
Applied
60%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
30334101080100%
Knowledge Area
303 - Genetic Improvement of Animals;

Subject Of Investigation
3410 - Dairy cattle, live animal;

Field Of Science
1080 - Genetics;
Goals / Objectives
1. Develop selection tools to enhance reproduction and survival using field data 2. Evaluate the biological and economic impact of crossbreeding on lifetime performance of dairy cattle 3. Develop breeding goals and appropriate indexes for optimum biological and economic improvement of health, reproduction, survival, and production of dairy cattle 4. Develop and recommend selection and crossbreeding protocols of optimum economic utility for adoption by US dairy farmers Expected Outputs Objective 1: Evaluation of daily body weight and its change on possible genetic association with metabolic diseases that predispose cows to premature death. Objective 2: Evaluation of Brown Swiss, Jersey, Montbeliarde and Swedish Red crossbreds for reproduction, lactation yields and survival. Objective 3: Develop breeding goals and appropriate indexes for optimum biological and economic improvement of health, reproduction, survival, and production of dairy cattle. 1. AIPL and various participating station collaborators: A. Development of an improved profit function to enhance the calculation of the lifetime net merit index and assessment of genetic evaluations of discounted net present value as an alternative economic measure. B. Evaluation of multiple genetic rankings for different markets (e.g. heifers, grazing, different breeds, different milk markets). C. Expansion of genetic evaluation of reproduction to other cow fertility traits in addition to daughter pregnancy rate. D. Evaluation of usefulness in genetic evaluations of health traits recorded via on-farm computers and other data such as milking speed and other non-traditional traits from research herds, cooperator herds and regional data sets. Assessment of the value of fertility, health, mastitis, body condition, feeds costs, etc. for inclusion in breeding goals or indexes. Objective 4: Develop and recommend selection and crossbreeding protocols of optimum economic utility for adoption by US dairy farmers. 1. AIPL and other participating project cooperators-Assessment of alternative breeding strategies and mating schemes to exploit additive and non-additive genetic variation to produce the most economically efficient dairy cattle for commercial milk production.
Project Methods
Objective 1: PA will analyze daily body weight and milk production using random regression models. Disease incidence will be regressed on genetic evaluations for body weight to approximate genetic correlations between disease and daily body weight change. Mastitis will be analyzed over test day intervals and in multiple trait models with yield and SCS. Dairy herd survey results will be combined with culling and pedigree data from DRMS to determine what herd management, environmental and genetic factors place cows at risk of dying on Pennsylvania dairy farms. Objective 2: PA will evaluate the biological and economic impact of crossbreeding of Brown Swiss and Holstein crosses on lifetime performance traits under commercial conditions using records kept in on-farm computing systems. Backcrosses will be available to enable estimation of recombination losses. Objective 3: Research on the value of fertility, health, mastitis, body condition score, feed costs, salvage value, and management traits will be conducted jointly with FL, GA, MN, NC, PA, TN, VA, and WI in addition to independent studies from these stations.

Progress 10/01/11 to 09/30/12

Outputs
OUTPUTS: The long term output of this project is the development of dairy cows that efficiently convert feed resources into milk. The gains in feed efficiency will occur without compromising cow health and reproductive fitness. Research focused on how efficiently cows digest feed and the relationship of milk production efficiency with cow fertility, survival and metabolic profiles. The performance of crossbred cows in grazing herds, telomere length variation among cows, and the associations of cow survival with herd management system were also evaluated. Results of the project have been disseminated to dairy producers through popular press articles in Hoard's Dairyman and Farmshine. Updates on emerging issues in genetic selection also were presented to dairy veterinarians at the annual American Association of Bovine Practitioners convention. Fellow research scientists and bull stud personnel were updated at the annual meeting of the American Dairy Science Association. PARTICIPANTS: This project has been overseen by Dr. Chad Dechow from Penn State University. Data editing and analysis of feed efficiency and fertility has been conducted by Jennifer Vallimont. Dustin Brown (Penn State graduate student) conducted crossbreeding and telomere research. Penn State undergraduates Jennell Counter, Gary Closs, Scott Rhode, Isaac Haagen, Hannah Rzepecki, and Alexa Woolcock have assisted in data collection, analysis and laboratory work. TARGET AUDIENCES: The target audiences for this research are dairy producers and bull stud personnel that will implement the recommended selection strategies. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Cows genetically inclined toward higher levels of feed efficiency were demonstrated to have lower levels of fertility, lower levels of blood glucose, higher levels of growth hormone, and longer lifespans. These results emphasize the need for balanced breeding programs that consider all economically important aspects dairy cattle production. Alternative measures of measuring feed efficiency are also needed due to the high cost of collecting feed intake data. A pilot project is currently being conducted to determine how much variation exists amongst cows in their ability to digest feed completely. It also was demonstrated that genetic selection for a longer lifespan helped to reduce cow mortality rates, particularly in cow management systems that had poor cow health and survival. Telomeres have been suggested as an indicator of stress in humans and other animals. We demonstrated that telomeres shorten slightly with age and that cows with short telomeres were more likely to be culled. Crossbred cows are popular in grazing environments that have a low level of concentrate supplementation. Our research suggests that Normande crossbreds maintain milk production levels during periods of slow pasture growth in a more stable manner than traditional dairy breeds due to an ability to mobilize more body tissue, but their milk production levels were inferior to traditional dairy breeds during other periods of the year.

Publications

  • Brown, D. E., C. D. Dechow, W. S. Liu, K. J. Harvatine, and T. L. Ott. 2012. Hot topic: Association of telomere length with age, herd, and culling in lactating Holsteins. J. Dairy Sci. 95:6384-6387.
  • Dekleva, M. W., C. D. Dechow, J. M. Daubert, W. S. Liu, G. A. Varga, S. Bauck, and B. W. Woodward. 2012. Short communication: Interactions of milk, fat, and protein yield genotypes with herd feeding characteristics. J. Dairy Sci. 95:1559-1564.


Progress 10/01/10 to 09/30/11

Outputs
OUTPUTS: The long term output of this project is improved genetic selection for dairy cows that produce milk efficiently, reproduce efficiently, and maintain high levels of health and welfare. Several studies were conducted in order to realize this long term goal. Research focused on the relationship between milk production efficiency and cow fertility, energy balance in grazing herds, and the association of cow survival with herd management system. Results of the project have been disseminated to dairy producers at conferences such as the Delmarva Dairy Days and Mid-Atlantic Nutrition Conference. Updates on emerging issues in genetic selection also were presented to dairy veterinarians that participated in the Dairy Production Medicine Program at Penn State. Fellow research scientists and bull stud personnel were updated at the annual meeting of the American Dairy Science Association. Lastly, a software program was developed for dairy producers to see the results of genetic selection within their own dairy herd. The program demonstrates to producers how the top 25 percent of cows based on genetic potential compare to the bottom 25 percent of their herd for milk yield, fat yield, protein yield, somatic cell score, and herd life. The tool was unveiled during a seminar at Penn State's Ag Progress Days and gave producers the opportunity to preview the program by looking at data from their own herd. PARTICIPANTS: This project has been overseen by Dr. Chad Dechow from Penn State University. Data editing and analysis of feed efficiency and fertility has been conducted by Jennifer Vallimont. Scott Rhode (Penn State undergraduate) assisted in analysis of cow mortality and survival. Dustin Brown (Penn State graduate student) assigned body condition scores in grazing herds, and Jennell Counter (Penn State undergraduate) assisted in data entry and editing. Robert Goodling developed software for herd genetic trend demonstration. TARGET AUDIENCES: The target audiences for this research are dairy producers and bull stud personnel that will implement the recommended selection strategies. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Cows genetically inclined toward higher levels of feed efficiency were demonstrated to have lower levels of fertility. These results emphasize the need for balanced breeding programs that consider all economically important aspects dairy cattle production. It also was demonstrated that intensive cow management systems have an adverse effect of cow survival. Cows in the most intensive management system considered (free-stalls that did not allow pasture access) have on-farm mortality rates that were 4 times greater than the most optimal system for survival (tie-stalls that allowed pasture access and that did not feed total mixed rations). There was evidence of genotype by environment interactions for cow survival. Selection of sires with high genetic potential for daughter herd life was associated with a 2.2 percent reduction in mortality and 2.7 percent reduction in culling before 60 days in milk in herds with an adverse cow survival environment. Smaller reductions in mortality and early lactation culling were observed in herds that had favorable cow survival environments. Cows in the top 25 percent of herds with at least 40 sire identified daughters for milk yield genetic potential had realized milk yields that were higher than the bottom quartile of cows in 90 percent of herds, demonstrating the reliability of our national genetic evaluation system. Body condition scores were collected on 7 cows in grazing herds in the Northeast. It was demonstrated that cows of the Normande breed maintained higher levels of body condition than Holsteins, which may help them maintain performance during periods of low pasture growth.

Publications

  • Brown, D. E. and C. D. Dechow. 2011. Body condition score comparisons of crossbred Normande-sired cows with herd mates sired by Ayrshire, Holstein, and Jersey. J. Dairy Sci. 94:(E-Suppl. 1)2.
  • Dechow, C. D., E. A. Smith, and R. C. Goodling. 2011. The effect of management system on mortality and other welfare indicators in Pennsylvania dairy herds. Anim. Welfare. 20:145-158.
  • Dechow, C. D., R. C. Goodling, and S. P. Rhode. 2011. The effect of sire selection on cow mortality and early lactation culling in adverse and favorable cow survival environments. Prev. Vet. Med. http://dx.doi.org/10.1016/j.prevetmed.2011.09.020.
  • Dechow, C. D., H. D. Norman, R. C. Goodling, and J. R. Wright. 2011. The association of high and low parent average with performance for yield, somatic cell score, and productive life in individual herds. J. Dairy Sci. 94:(E-Suppl. 1)28.
  • Vallimont, J. E., C. D. Dechow, J. M. Daubert, M. W. Dekleva, and J. W. Blum. 2011. Genetic association of days open with feed intake and efficiency. J. Dairy Sci. 94:(E-Suppl. 1)706-707.
  • Vallimont, J. E., C. D. Dechow, J. M. Daubert, M. W. Dekleva, J. W. Blum, C. M. Barlieb, W. Liu, G. A. Varga, A. J. Heinrichs, and C. R. Baumrucker. 2011. Short communication: Heritability of gross feed efficiency and associations with yield, intake, residual intake, body weight, and body condition score in 11 commercial Pennsylvania tie stalls. J. Dairy Sci. 94:(4)2108-2113.


Progress 10/01/09 to 09/30/10

Outputs
OUTPUTS: Previous research has demonstrated that crosses among Holstein and Brown Swiss have milk yield levels that are comparable to pure Holstein. Survival analysis is now being conducted for these breed groups and mean herd life estimates are 227 days longer for crosses than pure Holstein. Data is now being collected from grazing herds to compare performance of traditional pure breeds with Normande cattle at different levels of grain supplementation. Preliminary analyses of within-herd genetic trends and response to selection have been completed in cooperation with scientists from the Animal Improvement Program Laboratory at USDA. A favorable response to selection has been demonstrated across herds of different sizes and production levels; however, selection responses are greater in high yielding herds. We also have demonstrated that there is wide variation in colostrum immunoglobulin content. Results from analysis of within-herd response to genetic selection were presented at the American Dairy Science Association meeting in Denver, CO, and colostrogenesis research has been published in the Journal of Dairy Science. Results are presented annually to members of the S-1040 regional research project. PARTICIPANTS: This project has been overseen by Dr. Chad Dechow from Penn State University. Data editing and survival analysis for Brown Swiss x Holstein crosses has been conducted by Jennell Coulter (Penn State undergraduate). The analysis of within herd response to selection has been primarily conducted by Jan Wright from Animal Improvement Program Laboratory at USDA under the supervision of Dr. Duane Norman. Dechow and Robert Goodling (Penn State Cooperative Extension) have advised on study design and data interpretation. Analysis of colostrum content has been conducted by Dr. Craig Baumrucker (Penn State Faculty) with the assistance of Adam Burkett (Penn State undergraduate). TARGET AUDIENCES: The target audiences for this research are dairy producers and bull stud personnel that will implement the recommended selection strategies. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Smaller profit margins on dairy farms have demanded renewed focus on cost control. Extending herd life helps to reduce costs to dairy operations by reducing expenditures related to growing replacement animals. This research has helped clarify how inclusion of Brown Swiss in crossbreeding systems impacts herd life, and will ultimately help producers reduce input costs. An additional outcome is that selection pressure for survival within purebred populations will elevate to combat competition from crossbreeding, which will improve survival in our dairy cattle population irrespective of the adoption rate of crossbreeding. Understanding mechanisms of colostrogenesis will further facilitate improvements in survival by aiding the development of strategies to increase colostrum delivery to calves, thereby reducing calf mortality. We also have shown that response to genetic selection can be demonstrated within a dairy herd. This information will be used to build web applications that producers can access that will help them make more informed genetic selection decisions, and thus improve the profitability of their dairy herds.

Publications

  • Baumrucker, C. R., A. M. Burkett, A. L. Magliaro-Macrina, and C. D. Dechow. 2010. Colostrogenesis: Mass transfer of immunoglobulin G1 into colostrums. J. Dairy Sci. 93:03031-3038.
  • Norman, H. D., J. R. Wright, C. D. Dechow, and R. C. Goodling Jr. 2010. Effectiveness of genetic evaluations in predicting daughter performance in individual herds. J. Dairy Sci. Vol. 93, E-Suppl. 1:612.


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: A summary of the top Holstein sires, dams and breeder herds have been summarized and published at: http://dasweb.psu.edu/bullrank/. The summaries report those animals and herds with artificial insemination sons that have the highest Lifetime Net Merit, type, udder composite, milk yield, fat yield, protein yield, productive life, daughter pregnancy rate, and somatic cell score. Results have also been disseminated through peer-reviewed publications (Journal of Dairy Science) to the scientific community, and through popular press articles in Dairy Digest and Progressive Dairyman. PARTICIPANTS: The principal investigator for the project was C.D. Dechow. One M.S. student (M.W. Dekleva), 1 Ph.D. candidate (E. Frigo), and 2 undergraduate students (E.A. Smith and S.M. Hall) participated in the project. One Senior Research Technologist (J. Vallimont) participated in the project. There was collaboration with scientists from Virginia Tech (B. Cassell) the University of Milan (E. Frigo and O. Pedron), Select Sires (C. Sattler), Dairy Records Management Systems (J. Clay), and members of the S-1040 Multistate research project. TARGET AUDIENCES: The target audience is dairy researchers and producers in order to improve the well-being and efficiency of dairy cows. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Genetic relationships of automated daily body weights taken from a walk-through scale as cows exit the milking parlor during the first 120 days of lactation were associated with metabolic diseases, ketosis, infectious diseases, mastitis, reproductive diseases, and other diseases. Correlations among predicted transmitting ability for body weight traits and genomic predicted transmitting ability for productive and type traits were also estimated. Heritability estimates for daily body weight ranged from 0.34 to 0.63. Higher body weight and less body weight change were correlated with less ketosis, metabolic diseases, infectious diseases, and other diseases. A higher predicted transmitting ability for body weight was significantly correlated with lower genomic predicted transmitting ability for milk yield, dairy form, rear udder height and udder cleft. It was concluded that selection for reduced weight loss can be implemented with automated body weighing systems and may be successful in decreasing disease incidence in the early stages of lactation. In addition to daily body weight and health measures from research herds, mastitis records from commercial dairy farms were analyzed to determine if they could facilitate genetic evaluations for mastitis in the US. The edited data contained 118,516 lactation records and 1,072,741 test-day records of 64,893 cows. The overall incidence of clinical mastitis was 15.4% and heritability estimates ranged from 0.73% to 11.07% depending on the method of analysis. Increased mastitis incidence was genetically correlated with higher SCS and was generally correlated with higher yield, particularly during first lactation. Significant genetic variation exists for clinical mastitis, and health events recorded by producers could be used to generate genetic evaluations for cow health.

Publications

  • Dechow, C.D. 2009. Crossbreeding: Strengths and weaknesses, here and abroad. Progressive Dairyman. Aug. 2009. http://www.progressivedairy.com/phpBB2/viewtopic.phpp=2913&sid=07b6b 36ade97bb838e38c52287048581.
  • Dechow, C.D. 2009. Genomic genetic evaluations have arrived. Dairy Digest. February 2009. pp. 5-7.
  • Dechow, C.D. 2009. Mortality and early lactation cull rates in Pennsylvania dairy herds. Dairy Digest. April 2009. pp. 1-2.
  • Frigo, E., C.D. Dechow, O. Pedron, and B.G. Cassell. 2009. The Genetic Relationship of Body Weight and Early Lactation Health Disorders in Two Experimental Herds. J. Dairy Sci. (Accepted for Publication).
  • Vallimont, J.E., C.D. Dechow, C.G. Sattler, and J.S. Clay. 2009. Heritability estimates associated with alternative definitions of mastitis and correlations with somatic cell score and yield. J. Dairy Sci. 92:3402-3410.