State and National Standardized Lactation Averages by Breed for Cows Calving in 1996

Dairy cow lactation data used in genetic evaluations and in other U.S. Department of Agriculture (USDA) research originate in herds that are enrolled in the National Cooperative Dairy Herd Improvement Program. Lactation records are provided to the Animal Improvement Programs Laboratory by dairy records processing centers. Genetic evaluations have historically been computed with records from herds enrolled in official test plans that include fat testing. Beginning in 1997, owner-sampler records that met certain requirements were included although evaluations for those cows were not released. One of the requirements was that cows had calved on or after July 1, 1996. Thus, some of the data in this reported were from owner-sampler records.

Lactation records were standardized for age-parity, month of calving, previous dry period, times milked per day, and length of lactation. Records in progress and other records that were shorter than 305 days were projected to 305 days. Component percentages were computed from average standardized yields for milk and components. Protein testing is at or near 100% except in California.

This report includes only data eligible for use in calculation of genetic evaluations. Thus, records beyond fifth lactation or by cows that lacked a first lactation record were excluded.

The numbers and average standardized yields of lactation records that were initiated in 1996 and eligible to contribute to genetic evaluations are in Tables 1 through 4 by state and breed. The numbers of records and national average yields are in Table 5 by breed for 1970, 1980, 1990, 1992, 1994, and 1996. Numbers of records decreased from 1994 to 1996 with losses of 22% for Guernseys, 18% for Red and Whites, 16% for Ayrshires, and 5 to 9% for other breeds. Losses since 1990 were 49% for Guernseys and 37% for Ayrshires. Other breeds declined by 1 to 9% over those 6 years. Average milk yields increased by 6 to 13% across breeds since 1990 but only by 0 to 2% since 1994, except for a 3% decrease for Red and Whites. Fat percentages tended to increase slightly following the decline from 1992 to 1994 except for Jerseys, for which fat percentage continued to decrease. Protein percentages generally declined slightly.

Changes in the numbers of records and average yields result from many factors. Genetic change is expected to have a positive effect on yield, whereas feed availability and other operating costs, milk and beef prices, government programs, and characteristics of herds entering and leaving eligible testing programs can affect production averages in either direction.

Reviewed by: J.F. Keown, University of Nebraska, Lincoln, Nebraska; J. Pinter, AgSource Cooperative Services, Verona, Wisconsin; and M. Sieber, National Association of Animal Breeders, Columbia, Missouri.

Table 1. Number of records and state and national standardized lactation averages for Ayrshires and Brown Swiss used in genetic evaluations and calving in 1996.

State¹	Ayrshire							Brown Swiss
	Records	Milk (lb)	Fat (%)	Fat (lb)	Records with protein (%)	Pro- tein (%)	Pro- tein (lb)	Records	Milk (lb)	Fat (%)	Fat (lb)	Records with protein (%)	Pro- tein (%)	Pro- tein (lb)
Alabama	9	12,714	2.76	351	100	3.20	407	24	16,267	3.65	593	100	3.43	558
Alaska	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Arizona	—	—	—	—	—	—	—	384	21,116	3.73	787	100	3.42	723
Arkansas	11	10,857	3.79	411	100	3.25	353	81	14,810	3.49	516	100	3.44	510
California	5	14,758	3.77	556	80	3.30	466	811	18,066	3.99	721	98	3.56	642
Colorado	172	17,134	3.53	606	100	3.31	566	248	17,652	4.05	714	100	3.45	610
Connecticut	135	17,159	4.04	694	99	3.41	586	59	16,147	3.93	635	100	3.45	557
Delaware	62	16,948	3.85	652	100	3.36	569	1	15,357	4.78	734	100	3.27	502
Florida	2	11,934	2.79	334	100	3.30	394	16	16,932	3.90	660	94	3.41	567
Georgia	59	10,944	3.63	397	100	3.29	360	80	16,259	3.64	591	100	3.41	555
Hawaii	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Idaho	25	13,860	3.73	517	100	3.47	481	241	19,083	4.04	771	100	3.58	682
Illinois	320	15,828	3.90	618	100	3.33	528	670	18,070	4.00	722	100	3.55	641
Indiana	248	16,167	3.84	621	100	3.32	536	664	18,637	4.08	760	100	3.62	674
Iowa	633	16,220	3.94	639	100	3.31	537	1,818	18,387	4.10	753	100	3.52	647
Kansas	202	14,989	3.88	581	100	3.38	507	268	18,375	4.02	738	100	3.50	642
Kentucky	24	12,916	3.64	470	100	3.33	430	132	15,046	3.79	571	100	3.49	525
Louisiana	2	15,075	3.34	504	100	3.20	483	29	14,370	3.62	521	100	3.46	497
Maine	156	16,629	3.84	639	100	3.29	547	63	14,290	3.82	547	100	3.44	492
Maryland	299	16,585	3.97	659	100	3.30	547	330	19,102	4.12	788	100	3.48	664
Massachusetts	40	14,899	3.83	571	100	3.39	505	101	18,817	3.94	742	100	3.49	657
Michigan	187	16,758	3.90	654	100	3.34	560	253	19,376	4.08	791	100	3.54	685
Minnesota	285	13,897	3.95	548	100	3.26	453	1,343	17,017	4.09	696	99	3.49	595
Mississippi	1	16,808	3.21	540	100	2.98	501	5	15,590	3.39	529	100	3.38	527
Missouri	90	15,146	3.75	567	100	3.28	497	356	17,304	3.82	661	100	3.53	611
Montana	1	14,839	4.00	594	100	3.34	496	71	16,302	3.93	641	100	3.49	570
Nebraska	90	14,539	3.88	564	100	3.28	477	456	20,082	3.87	777	100	3.55	714
Nevada	—	—	—	—	—	—	—	3	18,647	3.80	708	100	3.53	658
New Hampshire	152	15,633	3.93	615	100	3.33	520	130	15,629	3.95	618	100	3.46	540
New Jersey	38	13,924	4.34	605	100	3.35	466	35	15,972	4.14	661	100	3.47	555
New Mexico	289	16,402	3.80	623	96	3.29	539	39	18,647	3.71	691	100	3.36	627
New York	1,356	15,246	3.93	599	100	3.31	504	759	16,777	4.13	693	100	3.47	582
North Carolina	127	13,346	3.42	456	100	3.25	434	87	15,554	3.96	616	100	3.47	540
North Dakota	5	13,138	3.94	518	100	3.27	430	46	16,953	4.00	678	100	3.58	606
Ohio	645	15,981	3.85	616	100	3.32	531	1,306	18,942	4.07	771	100	3.54	671
Oklahoma	188	17,670	3.58	633	100	3.28	579	157	16,241	3.78	614	100	3.51	570
Oregon	118	16,142	4.03	650	100	3.47	560	318	18,562	4.07	756	100	3.50	650
Pennsylvania	1,056	16,050	3.83	614	100	3.32	533	998	17,559	4.02	706	100	3.49	613
Puerto Rico	—	—	—	—	—	—	—	182	12,380	3.10	384	100	3.36	416
Rhode Island	31	14,763	4.02	593	100	3.33	492	2	16,613	3.55	591	100	3.61	600
South Carolina	—	—	—	—	—	—	—	—	—	—	—	—	—	—
South Dakota	—	—	—	—	—	—	—	382	16,071	4.23	680	100	3.59	577
Tennessee	76	12,826	3.92	503	99	3.34	433	216	17,107	3.68	630	100	3.50	598
Texas	5	14,007	3.75	525	100	3.43	480	558	16,588	3.88	644	100	3.45	573
Utah	14	13,864	4.16	577	93	3.47	487	14	17,129	4.08	699	100	3.50	600
Vermont	526	15,696	3.88	610	100	3.34	524	219	16,918	4.04	683	100	3.51	594
Virginia	206	15,411	3.63	560	100	3.36	518	154	18,578	3.75	697	100	3.46	642
Washington	78	17,949	3.80	682	100	3.40	610	222	19,245	3.53	679	100	3.54	681
West Virginia	176	13,273	3.99	529	100	3.32	440	2	12,325	4.41	544	100	3.90	481
Wisconsin	661	15,350	3.89	597	100	3.31	509	2,667	17,678	4.10	725	100	3.51	620
Wyoming	—	—	—	—	—	—	—	—	—	—	—	—	—	—
United States¹	8,804	15,658	3.86	605	100	3.32	520	16,997	17,830	4.01	715	100	3.51	626

Table 2. Number of records and state and national standardized lactation averages for Guernseys and Holsteins eligible for use in genetic evaluations and calving in 1996.

State¹	Guernsey							Holstein
	Records	Milk (lb)	Fat (%)	Fat (lb)	Records with protein (%)	Pro- tein (%)	Pro- tein (lb)	Records	Milk (lb)	Fat (%)	Fat (lb)	Records with protein (%)	Pro- tein (%)	Pro- tein (lb)
Alabama	2	11,172	4.65	520	100	3.83	428	4,307	18,514	3.44	638	100	3.09	573
Alaska	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Arizona	81	15,620	4.06	634	100	3.32	518	20,310	22,760	3.51	800	99	3.03	691
Arkansas	48	13,276	3.93	522	100	3.49	463	2,905	18,392	3.38	622	100	3.12	574
California	520	15,899	4.47	710	87	3.54	569	314,008	23,030	3.57	823	71	3.16	730
Colorado	3	14,436	4.28	618	100	3.44	497	12,935	23,255	3.43	797	99	3.12	726
Connecticut	47	12,612	4.63	585	100	3.42	431	9,419	22,645	3.57	808	100	3.11	705
Delaware	1	14,268	3.87	552	100	3.20	457	2,914	21,936	3.61	791	100	3.12	685
Florida	7	9,467	3.92	371	100	3.47	328	5,719	20,376	3.36	685	100	3.06	624
Georgia	27	12,258	3.75	460	100	3.32	407	11,594	20,319	3.47	704	100	3.10	631
Hawaii	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Idaho	40	13,059	4.32	564	100	3.53	462	19,477	23,252	3.59	834	100	3.20	744
Illinois	513	14,241	4.43	630	100	3.46	494	31,986	21,290	3.64	775	100	3.17	675
Indiana	547	14,102	4.45	628	100	3.55	500	24,314	20,934	3.66	766	100	3.17	664
Iowa	917	14,025	4.45	625	100	3.49	490	47,277	21,523	3.66	788	100	3.16	680
Kansas	119	14,455	4.39	635	100	3.47	502	18,421	20,954	3.63	762	100	3.16	663
Kentucky	79	13,069	4.12	539	100	3.43	449	10,186	19,815	3.46	686	100	3.14	623
Louisiana	165	12,878	4.02	517	100	3.48	448	5,573	17,844	3.35	598	100	3.12	557
Maine	31	13,285	4.38	581	100	3.56	473	8,941	22,272	3.67	818	100	3.15	702
Maryland	476	15,065	4.49	676	100	3.45	520	25,655	21,170	3.70	783	100	3.15	666
Massachusetts	21	13,733	4.93	677	100	3.48	477	7,415	22,191	3.71	824	100	3.16	701
Michigan	222	12,868	4.60	592	100	3.55	457	71,108	22,423	3.84	861	100	3.13	703
Minnesota	1,130	13,628	4.55	620	100	3.43	468	147,141	21,219	3.75	796	100	3.12	662
Mississippi	3	11,258	3.91	440	100	3.62	408	6,793	19,747	3.53	696	100	3.18	629
Missouri	384	13,663	4.29	586	100	3.51	480	18,221	19,605	3.57	699	100	3.16	620
Montana	43	16,317	4.24	692	100	3.59	586	3,747	22,142	3.48	771	100	3.16	700
Nebraska	163	15,033	4.39	660	100	3.49	525	14,609	21,498	3.63	779	100	3.18	683
Nevada	—	—	—	—	—	—	—	4,007	22,788	3.58	816	98	3.12	713
New Hampshire	28	15,714	4.43	696	100	3.58	562	7,467	23,839	3.68	878	100	3.14	749
New Jersey	41	12,695	4.63	588	100	3.47	440	6,306	21,219	3.58	761	100	3.13	665
New Mexico	1	14,922	4.19	625	100	3.91	584	9,164	23,274	3.37	784	100	3.12	726
New York	783	13,849	4.52	626	100	3.45	479	164,442	21,612	3.67	793	100	3.11	671
North Carolina	149	14,337	4.33	621	100	3.49	500	17,790	20,945	3.53	739	100	3.09	647
North Dakota	1	13,141	4.69	616	100	3.

State and National Standardized Lactation Averages by Breed for Cows Calving in 1996

R.L. Powell Agricultural Research Service - USDA Beltsville, Maryland

R.L. Powell
Agricultural Research Service - USDA
Beltsville, Maryland