Evaluation and Utilization of the Slick Hair Gene in Florida and Caribbean Dairies

EVALUATION AND UTILIZATION OF THE SLICK HAIR GENE IN FLORIDA AND CARIBBEAN DAIRIES

Sponsoring Institution

National Institute of Food and Agriculture

Project Status

TERMINATED

Funding Source

SPECIAL GRANT

Reporting Frequency

Annual

Accession No.

0195147

Grant No.

2002-34135-12467

Project No.

FLA-ANS-04080-O

Proposal No.

2002-04484

Multistate No.

(N/A)

Program Code

Project Start Date

Sep 15, 2002

Project End Date

Sep 14, 2005

Grant Year

(N/A)

Project Director
Olson, T. A.

Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611

Performing Department
ANIMAL SCIENCES

Non Technical Summary
Heat stress contributes to reduced productivity of dairy cattle in Florida and throughout the Caribbean region. A single gene, the Slick hair gene has been identified that confers superior heat tolerance to cattle that possess it. The purposes of this study are to determine if lactating dairy cows in Puerto Rico respond in the same fashion to the incorporation of the Slick hair gene as cows in southern Florida, to locate the Slick hair gene in the bovine genome and to produce genetically superior cattle that are homozygous for the Slick hair gene.

Animal Health Component

(N/A)

Research Effort Categories

Basic

40%

Applied

60%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
303	3410	1080	75%
304	3410	1080	25%

Knowledge Area
303 - Genetic Improvement of Animals; 304 - Animal Genome;

Subject Of Investigation
3410 - Dairy cattle, live animal;

Field Of Science
1080 - Genetics;

Goals / Objectives
To valuate the effect of the slick hair gene on milk yield and reproductive performance in Puerto Rican dairies. This study, which will replicate a recently initiated study in Florida will compare the milk yield, reproduction performance, and survival rate of slick- and normal-haired 87.5% Holsteins in commercial dairies in Puerto Rico. To locate the slick hair gene. Subobjectives include saturating the critical region of the chromosome harboring the gene conferring the slick hair phenotype and identifying a marker suite defining the interval of maximum likelihood of harboring the slick hair gene. To exploit the slick hair gene through development of breeding stock for use in Florida and throughout the Caribbean region. Genetically superior breeding stock homozygous for the slick hair gene will be developed through the use of cloning, superovulation and embryo transfer technologies, in vitro production of embryos and possibly the importation of semen from a slick-haired dairy breed in Central America.

Project Methods
Semen from 75% Holstein: 25% Senepol bulls will be distributed to three or four cooperating Puerto Rican dairies to produce at least 100 lactating cows from Holstein dams. The milk yields, lactation length, milk fat percentages, services per conception, days open and calving intervals of slick vs. normal-haired daughters of these bulls will be compared during the summer vs. cooler months of the year. A reference population of 200 calves (7/8 Holstein x 1/8 Senepol)born at a Florida dairy in 2002 will have their DNA extracted and preserved. With marker genotypes assigned for the 3/4 Holstein x 1/4 Senepol bulls that sired the progeny, genotypes available from their grand dams and the great grandsire conferring the slick phenotype, these 200 will substantially increase the likelihood of detecting recombination events to further reduce the size of the critical region harboring the gene. Slick-haired 87.5% Holstein heifers will superovulated and bred using semen from elite Holstein sires as well as from superior slick-haired Holstein crossbred sires to produce progeny with high PTA (predicted transmitting ability) values for both milk and conformation traits. Clones of the most superior slick-haired Puerto Rican Holstein cow will be attempted to be produced by transferring a single cell from the slick-haired donor to the perivitelline space of enucleated eggs and fused. Fused clones will then be activated with ionomycin and 6-DMAP and placed into KSOM medium in a humidified environment of 5% CO2/5% O2/90% N, 39C for 6-7 days. Development will be assessed and viable clones will be transferred to synchronous recipient cows and carried to term.

Progress 09/15/02 to 09/14/05

Outputs
This particular project has terminated but the research continues as FLA-ANS-04080-O3 0200919. During the course of the project semen from three 75% Holstein: 25% Senepol bulls was utilized in a number of dairy herds in Puerto Rico. The same bulls were used in a large private herd in South Florida. Daughters of these bulls from Holstein cows are now in milk in the south Florida and milk production, reproductive, and heat tolerance data are being colleced on these cows. Preliminary analysis of these data indicate that while the slick-haired cows were more heat tolerant than their normal-haired siblings in terms of rectal temperatures, respiration rates and sweating rates, they did not produce more milk. However, the data collected to date is limited and most of the calvings to date have occurred in the months not as associated with heat stress. Earlier studies investigating the heat tolerance and grazing activities of 7/8 Holstein weaned bull calves with and without the Slick hair gene had shown that the slick-haired bull calves had only modestly lower rectal temperatures (neither slick nor normal-haired bulls were heat-stressed) but maintained these lower rectal temperatures with significantly lower respiration rates. The slick-haired bull calves also had greater grazing activities during the hotter periods of the day and gained at a higher rate. We were able to locate the genomic location of the Slick hair gene on Bovine Chromosome 20 as a result of research associated with this project. Subsequent research should allow us to identify very closely linked markers that will be useful in identifying sires that are homozygous for this dominant gene and, as a result, will only sire slick-haired, heat tolerant progeny. During the course of this research we have utilized superovulation and embryo transfer programs to incorporate the Slick hair gene into Holstein cattle with a high genetic potential for milk yield through use of semen from elite Holstein bulls on slick-haired donor females and now have 15/16 Holsteins, both bulls and heifers, sired by elite Holstein sires that show the slick-haired phenotype. In addition, in Puerto Rico, a small group of slick-haired Holstein cows has been assembled that possess the slick-haired phenotype and are not thought to descend from upgrading from the Senepol breed. It is believed that these females descend from Puerto Rican criollo cows with slick hair that were crossed with Holsteins and then subsequently backcrossed to Holstein for many generations. Because the Slick hair gene is dominant, and because we believe that it offered a selective advantage over normal-haired cows due to greater heat tolerance, animals with slick hair persisted in the population. An objective of the project which was unable to be realized was the use of cloning to replicate the genotype of a particularly productive slick-haired Holstein cow which was identified in Puerto Rico.

Impacts
Dairy cows suffer from heat stress in Florida and Puerto Rico for many months and this reduces both their milk production and fertility. The impact of the Slick hair gene is to allow an animal that possesses the gene to maintain a body temperature up to 0.5 degrees C lower than animals without the gene under periods of heat stress. This should allow them to maintain a higher feed intake and milk yield and maintain body temperatures below 40 degrees C which, in turn, should increase embryo survival and thus increase fertility. We expect that the greatest economic impact of the Slick hair gene will be in its use in dairies that have less infrastructure for cooling of their cows and those that utilize grazing. It should allow milk yields to remain higher during the hot months of the year relative to those of cooler months.

Publications

Olson, T. A., C.J. Lucena, C.C. Chase, Jr., and A.C. Hammond. 2003. Evidence of a major gene influencing hair length and heat tolerance in Bos taurus cattle. J. Anim. Sci. 81:80-90.
Paula-Lopes, F.F., C.C. Chase, Jr., Y.M. Al-Katanani, C.E. Krininger, III, R.M. Rivera, S. Tekin, A.C. Majewski, O.M. Ocon, T.A. Olson, and P.J. Hansen. 2003. Genetic divergence in cellular resistance to heat shock in cattle: Differences between breeds developed in temperate versus hot climates in responses of preimplantation embryos, reproductive tract tissues and lymphocytes to increased culture temperatures. Reproduction 125. 285-294.
Chase, C.C., Jr., M. Mariasegaram, J.X. Chaparro, T.A. Olson, R.A. Brenneman, and R.P. Niedz. 2006. Maping the locus causing the slick phenotype in Senepol-derived cattle. (Abstract to be presented at the Plant and Animal Genome XIV Conference, San Diego, California, January 14-18, 2006.)
Mariasegaram, M., C.C. Chase, Jr., J.X. Chaparro, T.A. Olson, and R.P. Niedz. 2006. Interval mapping confirms Slick hair gene localization to bovine chromosome 20. (Abstract to be presented at the Plant and Animal Genome XIV Conference, San Diego, California, January 14-18, 2006.)
Olson, T.A., C.C. Chase, Jr., M. Mariasegaram, C. Lucena and E. Godoy. 2006. A history of the evaluation of the Slick hair gene. (Invited presentation to be given at the Southern Section meetings of the American Society of Animal Science to be held in Orlando, FL February 4-8, 2006. An abstract will be published in the J. Anim. Sci.)

Progress 10/01/03 to 09/30/04

Outputs
The process of generation of slick and normal-haired sibling heifers continued during the past year in both Florida and in Puerto Rico. Approximately 200 heifers have been born from Holstein cows and sired by predominantly Holstein sires (75% and greater)that are heterozygous for the slick hair gene have been born at McArthur Farms in southern Florida. Approximately half of these heifers are slick-haired and half are normal-haired. The oldest of these heifers have begun to calve during the late summer and early fall and production, reproduction and health data are beginning to be collected on these cows. Thirty-nine heifers from this south Florida herd were transferred to the Dairy Research Unit (DRU) of the University of Florida where more intense evaluation of their heat tolerance relative to normal-haired Holsteins will be conducted. Five slick-haired, seven-eigths Holstein heifers from the DRU group were superovulated and had embryos collected from them which subsequently were transferred into recipient females. A group of 11 ET calves were born in the spring of 2004 which included red and white, slick-haired bulls and heifers that may be homozygous for the slick hair gene. Also, slick-haired, fifteen-sixteenths Holstein calves were born sired by BW Marshall, an elite Holstein sire. In Puerto Rico about 60 heifer calves have been born to date sired by three-quarters Holstein, slick-haired bulls in various herds. In addition, seven slick-haired Holstein cows have been assembled in the University of Puerto Rico herd from private herds. A slick-haired son of one of these cows has been identified for future use in both Florida and Puerto Rico.

Impacts
Dairy cows suffer from heat stress in Florida and Puerto Rico for many months and this reduces both their milk production and fertility. The impact of the Slick hair gene is to allow an animal that possesses the gene to maintain a body temperature up to 0.5 degrees C lower than animals without the gene under periods of heat stress. This should allow them to maintain a higher feed intake and milk yield and maintain body temperatures below 40 degrees C which, in turn, should increase embryo survival and thus increase fertility.

Publications

No publications reported this period

Progress 10/01/02 to 10/01/03

Outputs
Semen from 3/4 Holstein: 1/4 Senepol bulls has been used in a large dairy in south Florida near Okeechobee and at several dairies in Puerto Rico. Slick and normal-haired bull calves from the Okeechobee herd were purchased after weaning and transferred to the Subtropical Agricultural Research Station. Studies of grazing behavior, rectal temperatures and respiration rates were conducted during the summer months of 2003. Slick-haired bulls had lower (P<0.01) respiration rates and quantities of clipped hair than their normal-haired siblings as well as having lower (P<0.05) AM rectal temperatures. Also, a higher percentage (P<0.05) of the slick-haired bulls was found to be grazing (as opposed to being in shaded areas) later during the morning and they returned to grazing sooner in the afternoon than did their normal-haired contemporaries. The slick-haired bulls also gained more weight (40.13 vs. 35.49 kg) throughout the grazing period of the study in spite of beginning the grazing period heavier due to faster gains while on feed on pasture during the spring months.

Impacts
Dairy cows suffer from heat stress in Florida and Puerto Rico for many months and this reduces both their milk production and fertility. The impact of the Slick hair gene is to allow an animal that possesses the gene to maintain a body temperature up to 0.5 degrees C lower than animals without the gene under periods of heat stress. This should allow them to maintain a higher feed intake and milk yield and maintain body temperatures below 40 degrees C which, in turn, should increase embryo survival and thus increase fertility.

Publications

Olson, T.A., Lucena, C., Chase, C.C., Jr., and Hammond, A.C. 2003. Evidence of a major gene influencing hair length and heat tolerance in Bos taurus cattle. J. Anim. Sci. 81:80-90.