Breed · Cattle

Holstein-Friesian: adverse event reports

FDA breed label "Holstein-Friesian also known as Holstein" · single-breed animals only

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An API dataset query result cannot be used to estimate the risk associated with the product or compare one drug or device product with another. When looking at the results, be aware that there is no certainty that the reported drug or device caused the adverse event. This dataset should not be the sole source of information for clinical decision-making or other assumptions about the safety or effectiveness of a product. The adverse event may have been related to an underlying disease, other drugs used at the same time or other non-drug related sources. FDA Center for Veterinary Medicine

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Not veterinary advice. This site lists what was reported to FDA. For an animal that is unwell, contact a veterinarian.

8,598reports, 1987–202627.5% of cattle reports

90reports, 12 months to March 202668 in the 12 months before

54%classed serious, as reportedall cattle: 58.4%

15.5%name monensinall cattle: 10.8%

FDA's database holds 8,598 reports where the animal's breed is given as "Holstein-Friesian also known as Holstein", shown here as Holstein-Friesian: 27.5% of reports about cattle. Reports on crossbred animals are left out of breed pages.

90 reports arrived in the 12 months to March 2026, up 32% from 68 in the 12 months before. A breed's count mostly mirrors how common the breed is; registration and ownership figures by breed are not public data, so no per-animal rate can be given.

By active ingredient, the drugs named most often are monensin, cephapirin sodium and ceftiofur hydrochloride. Monensin is named in 15.5% of this breed's reports, a larger share than in reports about all cattle (10.8%).

The terms listed most often are death (23.5%), residues in milk (11.6%) and alteration of milk quality (7.6%). Death appears in 23.5% of reports, a smaller share than in all cattle reports (29.4%). 54% of reports stating seriousness were classed as serious, against 58.4% for cattle overall.

Drugs named most often, by active ingredient

Active ingredients recorded for the drug	Reports	Share of Holstein-Friesian reports	Share of all cattle reports
Monensin	1,329	15.5%	10.8%
Cephapirin Sodium	495	5.8%	2.3%
Ceftiofur Hydrochloride	367	4.3%	2.1%
Dinoprost Tromethamine	249	2.9%	2.9%
Tulathromycin	240	2.8%	7.3%
Eprinomectin	227	2.6%	4.8%
Cephapirin Benzathine	179	2.1%	0.9%
Ceftiofur Sodium	169	2%	0.8%
Moxidectin	158	1.8%	4.2%
Vitamin E	138	1.6%	0.8%
Ceftiofur Crystalline Free Acid	133	1.5%	3.1%
Lincomycin Hydrochloride Monohydrate + Spectinomycin Sulfate Tetrahydrate	123	1.4%	0.6%
Oxytetracycline	117	1.4%	2.1%
Tilmicosin Phosphate	114	1.3%	2.6%
Penicillin G Procaine	107	1.2%	0.6%
Ivermectin	104	1.2%	6.9%
Cloxacillin Benzathine	102	1.2%	0.5%
Ampicillin Trihydrate	98	1.1%	0.5%
Tildipirosin	83	1%	1.3%
Doramectin	80	0.9%	10.3%

Ordered by report count. Differences from the species column often come from body size (which drugs a breed is prescribed) and from how common the breed was in the years a drug sold most. FDA states that these data cannot be used to estimate risk or to compare one product with another. Brand and manufacturer names are masked by FDA in these records.

Signs listed in reports

share of Holstein-Friesian reports listing the termall cattle reports

Death23.5%2,019
Residues in milk11.6%995
Alteration of milk quality7.6%654
Mastitis NOS[NOS: not otherwise specified]6.9%589
Lack of efficacy (bacteria) - NOS[the product did not have the expected effect: target not specified]6%513
Lack of efficacy - NOS[the product did not have the expected effect]5.9%505
Injection site swelling[swelling where the injection was given]5.4%461
Milk production decrease5.3%454
Diarrhoea[diarrhea]4.1%354
Anorexia[not eating]4%344
Recumbency[lying down and unable or unwilling to rise]3.6%306
Abortion3.3%283
Anaphylaxis[sudden severe allergic-type reaction]3.1%267
Ineffective, production (milk)[legacy FDA term: the product did not have the expected effect (production (milk))]3.1%266
Infertility NOS[NOS: not otherwise specified]2.8%244
Mammary gland oedema2.7%231
Weight loss2.6%227
Lack of efficacy (protozoa) - Coccidia[the product did not have the expected effect: coccidia]2.4%203
Dyspnoea[difficulty breathing]2.2%193
No sign[no clinical sign was reported]2.1%181
Lameness1.9%162
Collapse1.9%161
Residues in meat/offal1.9%160
Death by euthanasia[the animal was euthanized]1.8%159
Mammary gland disorder NOS[NOS: not otherwise specified]1.7%150

Age and weight

Age of the animal

Under 1 year12.2%1,047

1 to 3 years13.8%1,186

4 to 7 years14.9%1,282

8 to 11 years0.4%37

12 years and over0%4

Age not given58.6%5,042

Weight of the animal

Under 5 kg (11 lb)0%1

5 to 9.9 kg (11–22 lb)0%0

10 to 24.9 kg (22–55 lb)0%2

25 to 44.9 kg (55–99 lb)0.8%70

45 kg and over (99 lb+)49.1%4,221

Weight not given50.1%4,304

Coloured bar: Holstein-Friesian reports. Grey bar: all cattle reports.

Trend and outcomes

Reports by month FDA received them. The newest months are incomplete because FDA posts reports with a delay of three to six months.

Outcome recorded in the report

Recovered/Normal7.1%614

Recovered with Sequela1.1%93

Ongoing2.3%197

Died27.9%2,400

Euthanized1.6%138

Outcome Unknown15.4%1,322

Beside all cattle

Measure	Holstein-Friesian	All cattle
Reports	8,598	31,229
Latest 12 months	90	644
Classed serious, of reports stating it	54%	58.4%
Death or euthanasia recorded, per 1,000 reports	291.2	368

Questions about Holstein-Friesian reports

How many FDA adverse event reports involve Holstein-Friesians?

8,598 reports through March 2026, 27.5% of reports about cattle; 90 in the latest 12 months.

Which drugs are named most often in Holstein-Friesian reports?

By active ingredient: monensin (1,329), cephapirin sodium (495), ceftiofur hydrochloride (367), dinoprost tromethamine (249) and tulathromycin (240). Brands are masked in the public data.

What signs are reported most for this breed?

death (23.5%), residues in milk (11.6%), alteration of milk quality (7.6%), mastitis NOS (6.9%) and lack of efficacy (bacteria) - NOS (6%).

Is the Holstein-Friesian more sensitive to certain drugs?

Report counts cannot answer that. They show what was reported, not what a drug did, and they are not adjusted for how many Holstein-Friesian animals exist or were treated. Breed-related drug sensitivities that are established are described on FDA-approved labels; a veterinarian is the person to ask about an individual animal.

Why are crossbreds not included?

FDA records crossbred animals with one or more component breeds. Counting them under each component would double count, so breed pages use single-breed reports only. Crossbreds remain in the species totals.

How do I report a problem?

Call the drug company using the number on the label, or send Form FDA 1932a to FDA. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Animal & Veterinary adverse event bulk files released 28 Sep 2026, which hold reports FDA's Center for Veterinary Medicine received through 31 Mar 2026. openFDA masks brand and manufacturer names in these files, so drugs are counted by the active ingredients each record discloses and no figure is attributed to a brand, application or company. Ingredient names, and the separate reference lists of approved products, follow the FDA Green Book as of 1 Oct 2026. Breed names are FDA's labels rearranged into everyday order ("Holstein-Friesian also known as Holstein" becomes "Holstein-Friesian"). No report text, lot numbers or reporter details are published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.