Trends in Veterinary Drug Residues in US Cattle: Analysing USDA Sampling Data

ABSTRACT

Introduction

Cattle production is the leading agricultural industry in the United States, accounting for the largest portion of total cash receipts for agricultural commodities. The administration of veterinary drugs in food‐producing animals can lead to the presence of drug residues in food products.

Methods

The primary purpose of this study is to evaluate US national residue monitoring data to identify the most frequently detected veterinary drugs across various cattle types including dairy cows, beef cows, calves, heifers, and other types. Veterinary drug residue sampling reports and datasets for the years 2021, 2022, and 2023 were evaluated using descriptive statistical analysis to rank the most frequently detected drug residues in cattle.

Results

A total of 3391 positive veterinary drug residue samples (including both violative and non‐violative residues) were detected across all food animal species for the years 2021, 2022, and 2023 with cattle samples having the majority of positive detections (3107 samples; 92%). Across all three years, dairy cows accounted for the highest number of residue detections (1264), including both violative and non‐violative detections, compared with other cattle types, beef cows (505), bob veal (449), steers (384), and heifers (263). A Pearson's Chi‐squared test indicated that the distribution of residue detections varied among cattle types (χ² = 390.73, df = 11, p‐value < 0.0001). Among the violative residues, desfuroylceftiofur was the most frequently detected analyte (351 detections), followed by penicillin (161), flunixin (122), sulfadimethoxine (94), and sulfamethazine (79).

Conclusion

This study highlights consistent patterns in veterinary drug residue detections in cattle from 2021 to 2023 revealing major issues in residue control and compliance. These findings underscore the importance of addressing the persistent presence of certain veterinary drugs in cattle products, support the continued role of targeted residue monitoring programs, and inform future evaluations of drug use and surveillance priorities.

National US residue monitoring data (2021–2023) were analysed to characterise veterinary drug residue detections in cattle. Detection patterns varied by cattle type, with dairy cows accounting for the highest number of detections and a consistent group of commonly used drugs responsible for most violative and non‐violative findings.

1. Introduction

Cattle production is the leading agricultural industry in the United States, accounting for the largest portion of total cash receipts for agricultural commodities. In 2023, it was projected to contribute approximately 17% of the $520 billion in total agricultural cash receipts (U.S. Department of Agriculture 2025). The number of cattle slaughtered in the United States totalled approximately 33.9 million head in 2021, 34.3 million in 2022, and 32.8 million in 2023; moreover, beef and veal production in the United States amounted to approximately 28.06 billion pounds in 2021, 28.46 billion pounds in 2022, and 27.05 billion pounds in 2023 (United States Department of Agriculture 2025). Veterinary drugs are chemical agents used to treat or prevent diseases in food‐producing animals, supporting the safe and abundant production of meat, milk, eggs, and honey when administered according to Good Veterinary Practices (GVP) (Canton et al. 2021). Veterinary drugs are also employed to restore the physiological functions and address nutritional deficiencies which are essential for maintaining the health and welfare of animals (World Health Organization 2017). The administration of veterinary drugs in food‐producing animals can lead to the presence of drug residues in food products (Chicoine et al. 2020).

Impacts

• This study provides a comprehensive overview of veterinary drug residues detected in cattle across the United States between 2021 and 2023.

• Results show that dairy cattle accounted for the highest number of violative residue detections with antibiotics dominating the detections and a consistent group of drugs recurring across years.

• The study supports the United States Department of Agriculture's Food Safety and Inspection Service and the National Residue Program by providing evidence‐based insights to improve residue sampling strategies and promote compliance with withdrawal times, ultimately protecting public health.

The Joint FAO/WHO Expert Committee on Food Additives (JECFA) plays a critical role in evaluating the safe use of veterinary drug residues in food‐producing animals, including the establishment of maximum residue limits (MRLs), acceptable daily intakes (ADIs), and no‐observed‐adverse‐effect levels (NOAELs) to mitigate associated public health risks (WHO/FAO 2024). In the United States, veterinary drug residue monitoring and regulation are carried out by multiple agencies: the US Food and Drug Administration (FDA) Center for Veterinary Medicine (CVM) is responsible for the approval of veterinary drugs to be used in food animals and setting tolerance levels and drug withdrawal periods, the US Department of Agriculture's Food Safety and Inspection Service (USDA‐FSIS) oversees veterinary drug residues monitoring through the National Residue Program (NRP), and the Environmental Protection Agency (EPA) assesses environmental risks and establishes pesticide residue tolerances (U.S. Department of Agriculture 2025).

The most common classes of veterinary drugs detected in food matrices such as milk, meat, and eggs include antibiotics, antiparasitics, and anti‐inflammatory drugs (Delatour et al. 2018). The existence of drug residues in animal‐derived food products can be influenced by the pharmacological characteristics, along with physical, chemical, or biological processes involving the animals or their products. Furthermore, numerous risk factors can lead to the development of drug residues in food‐producing animals, including disease status, age of the animal, feeding practices, and pharmacokinetic processes such as absorption, distribution, metabolism, and excretion (Beyene 2016).

Improper use of veterinary drugs and failure to observe appropriate withdrawal periods are among the leading causes of residue contamination (Beyene et al. 2015). The monitoring process for veterinary drug residues typically involves two key steps: an initial screening using highly sensitive tests designed to minimise false‐negative results, followed by a confirmation step that ensures accurate quantification relative to established maximum residue limits (MRL) and correct identification with a low likelihood of false‐positive findings (Mensah et al. 2014). For instance, various analytical methods are used for detecting drug residues in food, including liquid chromatography‐tandem mass spectrometry (LC‐MS/MS), high‐performance liquid chromatography (HPLC), and enzyme‐linked immunosorbent assay (ELISA) (Tao et al. 2018).

The occurrence of veterinary drug residues, especially antibiotics, in animal‐derived food products such as meat, milk, eggs, and honey highlights a significant risk to public health and food safety. The use of veterinary products below or above the recommended levels may lead to short‐ or long‐term adverse health effects in humans including the development of resistant bacterial or parasitic strains, toxicity, allergic reactions, mutagenesis, teratogenicity, and carcinogenicity (Mesfin et al. 2024; Atta et al. 2022). Various outbreaks of veterinary drug residue poisoning have been reported globally. For instance, in Portugal, 50 individuals were affected by food poisoning after consuming lamb and beef contaminated with clenbuterol residues. Their symptoms included severe tremors, rapid heartbeat, nausea, headaches, and dizziness (Salleras et al. 1995; Barbosa et al. 2005). Furthermore, twelve people in Taiwan were hospitalised with symptoms of β‐agonist poisoning after eating contaminated fried chicken, and clenbuterol and salbutamol were later detected in their urine (Wu et al. 2013). Hence, effective monitoring and regulation of veterinary drug residues play a crucial role in the research, development, application, and oversight of veterinary drugs (Wu et al. 2023). Controlling the risks of veterinary drug residues requires extensive and collective measures, including strict regulation, enhanced surveillance, and improved drug use practices in food animals (Khalifa et al. 2024). The primary purpose of this study is to evaluate national data from the United States, specifically the cattle drug residue sampling reports generated under the National Residue Program (NRP), to identify and highlight the most frequently detected veterinary drugs across various cattle types including dairy cows, beef cows, calves, and other cattle types. This study addresses the lack of recent national summaries comparing veterinary drug residue detection patterns across cattle types using publicly available NRP data.

2. Materials and Methods

Veterinary drug residue sampling reports and datasets for the years 2021, 2022, and 2023 were evaluated to rank the most frequently detected drug residues in cattle. These samples were collected primarily by the US Department of Agriculture's (USDA) Food Safety and Inspection Service (FSIS) including the National Residue Program (NRP). The datasets were publicly available and accessed through the FSIS official website in CSV format. This analysis is limited to positive veterinary drug residue detections from edible solid tissues, primarily liver and kidney samples, with a smaller number of product samples, and does not include residue data from other matrices such as milk (FSIS 2025).

Descriptive statistical analysis was conducted using (R Core Team 2022, version 4.2.2) and RStudio (RStudio Team, version 2024.12.1 Build 563) to calculate residue counts and percentages of detected residues across different cattle types. Sampling reports included a wide range of food animal species such as sheep, goats, chickens, pigs, and fish; however, only cattle‐specific samples were selected and analysed for this study. The datasets were classified based on cattle type, veterinary drug residue detected, and whether the result was considered a positive violative or a positive non‐violative according to established US regulatory tolerances (maximum residue limits) defined by the FDA. The dataset includes only residue‐positive samples and lacks total samples tested; therefore, the analysis is limited to positives and cannot be used to estimate prevalence or violation rates.

Residue testing data derive from two sampling frameworks, including National Residue Program (NRP) surveillance sampling and inspector‐generated sampling. These approaches serve distinct purposes and therefore may represent different underlying sampling populations. According to the USDA FSIS annual residue monitoring reports, a total of 361,153 cattle samples were tested for veterinary drug residues in the United States over a three‐year period from 2021 to 2023. These included both National Residue Program (NRP) surveillance samples and inspector‐generated samples. In 2021, 136,731 samples were collected, comprising 2935 NRP samples and 133,796 inspector‐generated sampling. In 2022, a total of 120,415 samples were collected, including 2955 from NRP and 117,460 from inspector‐generated samples. In 2023, 104,007 samples were collected, consisting of 3145 NRP samples and 100,862 inspector‐generated samples (U.S. Department of Agriculture 2025).

3. Results

A total of 3391 positive veterinary drug residue samples were detected across all food animal species (e.g., cattle, sheep and goats, chicken, and pigs) in the USDA FSIS datasets for the years 2021, 2022, and 2023. Among these, cattle samples accounted for the majority of positive detections, with 3107 (92%) samples testing positive for at least one veterinary drug residue (Table 1).

TABLE 1.

Total of positive residue samples detected from all animal species vs. cattle and their percentages based on USDA FSIS data.

Year	All species residues detected	Cattle residues detected
2021	1150	1024 (89%)
2022	1214	1137 (94%)
2023	1027	946 (92%)
All years	3391	3107 (92%)

Across all three years, dairy cows accounted for the highest number of residue detections (1264), both violative and non‐violative compared to other cattle types, beef cows (505), bob veal (449), steers (384), and heifers (263) (Figure 1). A Pearson's Chi‐squared test was conducted to assess the association between cattle type and the presence of residues. The results indicated the distribution of residue detections differed significantly among cattle types (p‐value < 0.0001) and that dairy cows showed a higher detection of residues compared to other species in the top five. Among samples with detectable residues, bob veal accounted for a higher number of violative detections, particularly in 2022 and 2023. While steers and heifers had lower violative detections, their sample counts remained significant. Additionally, some meat products, including ground beef and veal, occasionally revealed positive analyte results indicating that product testing can result in residue detections (Table 2).

FIGURE 1.

Number of residues (including violative and non‐violative) detected in each cattle type based on each conclusion in 2021–2023. ‘Others’ include samples collected from bull, formula‐fed veal, heavy calf, nonintact beef, and raw intact beef.

TABLE 2.

Summary of violative and non‐violative residue detections by cattle type for the years 2021–2023.

FY 2021				FY 2022				FY 2023
Cattle type	Violative	Non‐violative	Total	Cattle type	Violative	Non‐violative	Total	Cattle type	Violative	Non‐violative	Total
Dairy cow	288 (57%)	216 (43%)	504	Dairy cow	218 (54%)	183 (46%)	401	Dairy cow	195 (54%)	164 (46%)	359
Beef cow	52 (33%)	103 (66%)	155	Beef cow	62 (33%)	125 (67%)	187	Steer	20 (12%)	143 (88%)	163
Bob veal	58 (49%)	60 (51%)	118	Steer	33 (18%)	149 (82%)	182	Beef cow	55 (37%)	94 (63%)	149
Steer	17 (17%)	81 (83%)	98	Bob veal	115 (64%)	65 (36%)	180	Bob veal	68 (64%)	38 (36%)	106
Heifer	16 (22%)	58 (78%)	74	Heifer	10 (11%)	82 (89%)	92	Heifer	16 (16%)	81 (84%)	97
Bull/stag	9 (20%)	35 (79%)	44	Bull/stag	19 (32%)	40 (68%)	59	Bull/stag	7 (17%)	34 (83%)	41
Heavy calf	4 (31%)	9 (69%)	13	Non‐formula‐fed veal	15 (71%)	6 (29%)	21	Non‐ formula‐fed veal	18 (60%)	12 (40%)	30
Non‐formula‐fed veal	2 (20%)	8 (80%)	10	Heavy calf	3 (37%)	5 (62%)	8	Ground beef	1 (100%)	0 (0%)	1
Intact beef	2 (50%)	2 (50%)	4	Bull	0 (0%)	4 (100%)	4
Ground beef	4 (100%)	0 (0%)	4	Raw intact beef	1 (50%)	1 (50%)	2
				Formula‐fed calf veal	0 (0%)	1 (100%)	1
Total	452	572	1024	Total	476	661	1137	Total	380	566	946

Note: All values represent numbers of residue detections. Percentages reflect the proportion of violative and non‐violative detections within each cattle type and fiscal year.

Among all positive cattle residue samples from 2021 to 2023, a total of 2785 detections (out of 3107) were attributed to the top 20 most frequently identified analytes including violative and detected non‐violative samples. Tulathromycin was the most detected drug residue, appearing in 687 samples, followed by desfuroylceftiofur (433), oxytetracycline (249), and penicillin (247). These four drugs alone accounted for nearly 52% of the residues detected from cattle samples. Among the top 20 most frequently detected drug residues in cattle samples from 2021 to 2023, 15 out of 20 were antibiotics, including commonly used agents such as tulathromycin, desfuroylceftiofur, penicillin, oxytetracycline, neomycin, and sulfadimethoxine. In contrast, five of the top 20 were non‐antibiotic drugs, including anti‐inflammatory agents (flunixin and meloxicam), antiparasitic compounds (eprinomectin and doramectin), and a growth promoter (ractopamine) (Table 3).

TABLE 3.

Counts of the top 20 detected residues samples (violative + non‐violative) in all cattle types during 2021–2023.

Analyte name	Count
Tulathromycin	687
Desfuroylceftiofur	433
Oxytetracycline	249
Penicillin	247
Flunixin	183
Sulfadimethoxine	122
Neomycin	118
Florfenicol	102
Eprinomectin	99
Tilmicosin	94
Sulfamethazine	84
Ampicillin	54
Tildipirosin	50
Meloxicam	46
Ractopamine	45
Gamithromycin	44
Doramectin	36
Danofloxacin	34
Spectinomycin	29
Tetracycline	29
Total	2785 (out of 3107)

Table 4 highlights the top 20 violative and non‐violative drug residues detected in cattle samples collected between 2021 and 2023. Among the violative residues, desfuroylceftiofur, a metabolite of ceftiofur, was the most frequently detected analyte (351detections), followed by penicillin (161), flunixin (122), sulfadimethoxine (94), and sulfamethazine (79). These top five violative residues accounted for a large share of all violative detections and reflect both antibiotic and anti‐inflammatory usage. For instance, some drugs such as desfuroylceftiofur, penicillin, flunixin, neomycin, florfenicol, tilmicosin, and ampicillin were found in both violative and non‐violative categories suggesting variable levels of residue concentration that can fall either above or below the established regulatory limits. For instance, desfuroylceftiofur was found 351 times as violative and 82 times as non‐violative. The top 20 violative and detected, non‐violative analytes also demonstrate a broad variety of drug classes, including antibiotics (e.g., penicillin, oxytetracycline, neomycin), anti‐inflammatories (e.g., flunixin, meloxicam), antiparasitic (e.g., eprinomectin), beta‐agonist growth promoter (e.g., ractopamine), and anticoccidial agent (e.g., lasalocid) (Table 4).

TABLE 4.

Counts of the top 20 violative and non‐violative residues samples in all cattle types during 2021–2023.

Analyte	Violative count	Analyte	Non‐violative count
Desfuroylceftiofur	351	Tulathromycin	687
Penicillin	161	Oxytetracycline	233
Flunixin	122	Eprinomectin	98
Sulfadimethoxine	94	Penicillin	86
Sulfamethazine	79	Desfuroylceftiofur	82
Tilmicosin	74	Flunixin	61
Neomycin	70	Neomycin	48
Florfenicol	62	Tildipirosin	46
Meloxicam	46	Gamithromycin	42
Ampicillin	35	Ractopamine	42
Ciprofloxacin	25	Florfenicol	40
Doramectin	19	Danofloxacin	34
Oxytetracycline	16	Sulfadimethoxine	28
Sulfamethoxazole	16	Tetracycline	28
Sulfathiazole	15	Desacetyl cephapirin	23
Enrofloxacin	13	Moxidectin	23
Gentamycin sulphate	13	Lasalocid	22
Spectinomycin	10	Tilmicosin	20
Dihydrostreptomycin	8	Ampicillin	19
Sulfadiazine	8	Spectinomycin	19
Total	1237 (out of 1308 violative)	Total	1681 (out of 1799 non‐violative)

Across fiscal years 2021 to 2023, the data indicates consistent detection patterns for several drug residues. Desfuroylceftiofur remains the most frequently detected violative analyte each year, followed by recurring detections of penicillin, flunixin, sulfadimethoxine, sulfamethazine, florfenicol, neomycin, and tilmicosin. This pattern indicates that a consistent group of drugs is responsible for the majority of violative residues, year after year. Additionally, the top 20 violative analytes account for the vast majority of violative detections each year with over 95% (Table 5).

TABLE 5.

Summary of the top 20 violative analytes detected in all cattle types in the years 2021–2023.

FY 2021		FY 2022		FY 2023
Analyte name	Violative count	Analyte name	Violative count	Analyte name	Violative count
Desfuroylceftiofur	130	Desfuroylceftiofur	119	Desfuroylceftiofur	102
Penicillin	79	Flunixin	56	Penicillin	38
Sulfamethazine	34	Penicillin	44	Flunixin	37
Sulfadimethoxine	33	Florfenicol	31	Sulfadimethoxine	34
Flunixin	29	Neomycin	30	Tilmicosin	34
Neomycin	25	Tilmicosin	30	Sulfamethazine	19
Meloxicam	21	Sulfadimethoxine	27	Ampicillin	16
Florfenicol	15	Sulfamethazine	26	Florfenicol	16
Ampicillin	11	Doramectin	16	Neomycin	15
Tilmicosin	10	Meloxicam	13	Meloxicam	12
Sulfadiazine	7	Ciprofloxacin	10	Ciprofloxacin	9
Ciprofloxacin	6	Sulfamethoxazole	9	Oxytetracycline	9
Ketoprofen	5	Ampicillin	8	Enrofloxacin	6
Salbutamol	5	Sulfathiazole	8	Gentamycin sulphate	6
Sulfathiazole	5	Dihydrostreptomycin	5	Spectinomycin	5
Gentamycin sulphate	4	Oxytetracycline	5	Sulfamethoxazole	3
Sulfamethoxazole	4	Spectinomycin	5	Tildipirosin	3
Dihydrostreptomycin	3	Desethylene ciprofloxacin	4	Desethylene ciprofloxacin	2
Enrofloxacin	3	Enrofloxacin	4	Florfenicol amine	2
Sulfadoxine	3	Diclofenac	3	Piperonyl butoxide	2
Total	432	Total	453	Total	370

Note: This summary highlights the top 20 out of 33 violative residues detected in 2021 accounting for 95% of the total for violative analytes found in that year which was 452. In 2022, the top 20 out of 35 violative residues detected account for 95% of all violative analytes detected during that year which were 476. For 2023, the top 20 out of 29 violative residues account for 97% of the entire violative analytes which were 380.

The top 15 non‐violative residues detected in cattle from 2021 to 2023 show similar patterns across years. Tulathromycin consistently ranks as the most frequently detected analyte, followed by repeated occurrences of oxytetracycline, penicillin, eprinomectin, desfuroylceftiofur, flunixin, and neomycin. Several of these drugs such as penicillin, desfuroylceftiofur, flunixin, and neomycin were also detected as violative residues. Additionally, the top 15 analytes accounted for over 87% of all non‐violative detections each year, reflecting a concentrated and consistent pattern in non‐violative residue findings (Table 6).

TABLE 6.

Counts of the top 15 non‐violative residues detected in cattle during the years 2021–2023.

FY 2021		FY 2022		FY 2023
Analyte name	Count	Analyte name	Count	Analyte name	Count
Tulathromycin	156	Tulathromycin	278	Tulathromycin	253
Oxytetracycline	95	Oxytetracycline	92	Oxytetracycline	46
Penicillin	45	Eprinomectin	38	Eprinomectin	33
Desfuroylceftiofur	34	Desfuroylceftiofur	28	Flunixin	22
Eprinomectin	27	Penicillin	22	Desfuroylceftiofur	20
Ractopamine	27	Neomycin	19	Penicillin	19
Flunixin	25	Tildipirosin	18	Gamithromycin	13
Tildipirosin	19	Florfenicol	17	Neomycin	13
Florfenicol	17	Danofloxacin	16	Ractopamine	13
Neomycin	16	Flunixin	14	Danofloxacin	12
Tetracycline	16	Gamithromycin	14	Doramectin	11
Gamithromycin	15	Moxidectin	11	Ampicillin	10
Sulfadimethoxine	13	Ketoprofen	10	Desacetyl cephapirin	10
Spectinomycin	11	Tetracycline	8	Tilmicosin	10
Moxidectin	8	Lasalocid	7	Lasalocid	9
Total	524	Total	592	Total	494

Note: This table highlights the top 15 non‐violative residues detected in cattle in 2021–2023. For 2021, the top 15 out of 33 residues account for 91.6% of the total non‐violative residues detected which was 572. For 2022, the top 15 out of 37 residues account for 90% of the total non‐violative residues detected which was 661. For 2023, the top 15 out of 42 residues account for 87% of the total non‐violative residues detected which was 566.

Non‐dairy cattle samples including those from beef cows, calves, steers, bob veal, heifers, bulls/stags, formula‐fed veal, non‐formula‐fed veal, heavy calves, and others showed a broad range of drug residue detections from 2021 to 2023. The year 2022 showed the highest number of drug residue detections in non‐dairy cattle, with 736 analytes identified, exceeding the number of detections observed in 2021 (520) and 2023 (587). Table 7 summarises only the top 20 most frequently detected non‐dairy analytes in each year representing over 96% total residues identified. Among violative residues in this subset, tilmicosin was the most detected analyte, followed by desfuroylceftiofur and neomycin. Other frequently detected violative drugs included flunixin, sulfamethazine, penicillin, florfenicol, and doramectin. On the other hand, non‐violative residues were more prevalent, with tulathromycin consistently ranking first, followed by oxytetracycline, and additional analytes such as neomycin, tildipirosin, ractopamine, florfenicol, eprinomectin, gamithromycin, and moxidectin appearing frequently (Table 7).

TABLE 7.

The top 20 non‐dairy cattle residues detected during the years 2021–2023.

FY 2021				FY 2022				FY 2023
Violative count		Non‐violative count		Violative count		Non‐violative count		Violative count		Non‐violative count
Neomycin	23	Tulathromycin	140	Desfuroylceftiofur	32	Tulathromycin	242	Tilmicosin	33	Tulathromycin	221
Desfuroylceftiofur	20	Oxytetracycline	63	Tilmicosin	28	Oxytetracycline	69	Flunixin	22	Oxytetracycline	35
Sulfamethazine	19	Ractopamine	27	Flunixin	27	Neomycin	19	Desfuroylceftiofur	16	Ractopamine	13
Penicillin	18	Tildipirosin	19	Neomycin	25	Tildipirosin	17	Neomycin	15	Danofloxacin	12
Flunixin	11	Neomycin	13	Florfenicol	24	Danofloxacin	16	Florfenicol	13	Neomycin	12
Tilmicosin	8	Florfenicol	12	Sulfamethazine	20	Eprinomectin	15	Sulfamethazine	13	Eprinomectin	11
Sulfadiazine	7	Eprinomectin	10	Doramectin	16	Florfenicol	15	Ciprofloxacin	9	Gamithromycin	10
Florfenicol	6	Gamithromycin	9	Penicillin	14	Moxidectin	11	Oxytetracycline	9	Doramectin	9
Meloxicam	6	Spectinomycin	8	Sulfamethoxazole	9	Gamithromycin	9	Penicillin	8	Lasalocid	9
Ciprofloxacin	5	Desfuroylceftiofur	7	Sulfathiazole	8	Ketoprofen	9	Enrofloxacin	6	Tilmicosin	9
Sulfadimethoxine	5	Moxidectin	7	Ciprofloxacin	7	Lasalocid	7	Meloxicam	6	Tildipirosin	8
Sulfamethoxazole	4	Danofloxacin	6	Meloxicam	6	Doramectin	5	Spectinomycin	5	Desfuroylceftiofur	7
Sulfathiazole	4	Lasalocid	6	Spectinomycin	5	Desfuroylceftiofur	4	Sulfadimethoxine	5	Penicillin	7
Enrofloxacin	3	Penicillin	6	Desethylene Ciprofloxacin	4	Ivermectin	4	Gentamycin sulphate	3	Piperonyl butoxide	6
Gentamycin sulphate	3	Ivermectin	5	Enrofloxacin	4	Penicillin	4	Sulfamethoxazole	3	Flunixin	5
Dipyrone	2	Tilmicosin	4	Diclofenac	3	Piperonyl butoxide	4	Tildipirosin	3	Florfenicol	4
Doramectin	2	Enrofloxacin	2	Florfenicol amine	3	Tilmicosin	4	Desethylene ciprofloxacin	2	Ketoprofen	4
Ketoprofen	2	Flunixin	2	Tylosin	3	Spectinomycin	3	Florfenicol amine	2	Moxidectin	4
Phenylbutazone	2	Piperonyl Butoxide	2	Ampicillin	2	Tetracycline	3	Piperonyl butoxide	2	Ampicillin	2
Ractopamine	2	Tetracycline	2	Gamithromycin	2	Desethylene ciprofloxacin	2	Sulfathiazole	2	Desacetyl cephapirin	2
Total	152	Total	350	Total	242	Total	462	Total	177	Total	390

Note: The above residues were collected from non‐dairy cattle samples including: beef cows, calves, steer, bob veal, heifer, bull/stag, formula‐fed veal, non‐formula‐fed veal, heavy calf, raw‐intact‐beef, raw‐nonintact‐beef, and others. The total residues detected during 2021 were 520 analytes, during 2022, 736 non‐dairy analytes were found, and 587 non‐dairy analytes were detected in 2023.

In the case of dairy cattle samples, the top 20 residues account for over 97% of total detections during the years 2021 through 2023 revealing a gradual year‐by‐year decrease in overall detections. Among violative residues, desfuroylceftiofur remained the most frequently identified analyte along with penicillin which consistently ranked second. Other violative drugs that appeared regularly across all years included flunixin, sulfadimethoxine, meloxicam, and ampicillin. Among non‐violative residues, tulathromycin, penicillin, flunixin, oxytetracycline, and eprinomectin revealed high detections during 2021, 2022, and 2023. Interestingly, desfuroylceftiofur appeared frequently in both violative and non‐violative categories during all years. Furthermore, a few analytes, such as doxycycline, sulfaethoxypyridazine, and salbutamol were detected only in selected years suggesting variability in drug detection patterns. Violative residues made up a fairly consistent proportion of total dairy analyte detections each year with approximately 57% in 2021, 54% in 2022, and 54% in 2023 (Table 8). Consequently, the data reveals that drug residue detections declined over time in dairy cattle while detections in non‐dairy cattle remained steady or increased.

TABLE 8.

Top 20 violative and non‐violative dairy analytes for the years 2021–2023.

FY 2021				FY 2022				FY 2023
Violative count		Non‐violative count		Violative count		Non‐violative count		Violative count		Non‐violative count
Desfuroylceftiofur	110	Penicillin	39	Desfuroylceftiofur	87	Tulathromycin	36	Desfuroylceftiofur	86	Tulathromycin	32
Penicillin	61	Oxytetracycline	32	Penicillin	30	Desfuroylceftiofur	24	Penicillin	30	Eprinomectin	22
Sulfadimethoxine	28	Desfuroylceftiofur	27	Flunixin	29	Eprinomectin	23	Sulfadimethoxine	29	Flunixin	17
Flunixin	18	Flunixin	23	Sulfadimethoxine	25	Oxytetracycline	23	Ampicillin	15	Desfuroylceftiofur	13
Meloxicam	15	Eprinomectin	17	Florfenicol	7	Penicillin	18	Flunixin	15	Penicillin	12
Sulfamethazine	15	Tulathromycin	16	Meloxicam	7	Flunixin	12	Meloxicam	6	Oxytetracycline	11
Ampicillin	10	Tetracycline	14	Ampicillin	6	Ampicillin	6	Sulfamethazine	6	Ampicillin	8
Florfenicol	9	Sulfadimethoxine	13	Sulfamethazine	6	Desacetyl cephapirin	6	Florfenicol	3	Desacetyl cephapirin	8
Ketoprofen	3	Desacetyl cephapirin	7	Dihydrostreptomycin	5	Sulfadimethoxine	6	Gentamycin sulphate	3	Sulfadimethoxine	8
Salbutamol	3	Gamithromycin	6	Neomycin	5	Gamithromycin	5	Doxycycline	1	Tetracycline	4
Dihydrostreptomycin	2	Florfenicol	5	Ciprofloxacin	3	Tetracycline	5	Tilmicosin	1	Gamithromycin	3
Neomycin	2	Ampicillin	3	Oxytetracycline	3	Dihydrostreptomycin	3			Doramectin	2
Sulfadoxine	2	Neomycin	3	Tilmicosin	2	Enrofloxacin	2			Florfenicol	2
Tilmicosin	2	Spectinomycin	3	Gentamycin sulphate	1	Florfenicol	2			Ivermectin	2
Butorphanol	1	Bifenthrin	1	Lincomycin	1	Ivermectin	2			Piperonyl butoxide	2
Ciprofloxacin	1	Cloxacillin	1	Salbutamol	1	Pirlimycin	2			Sulfaethoxypyridazine	2
Gentamycin sulphate	1	Dihydrostreptomycin	1			Spectinomycin	2			Ketoprofen	1
Oxytetracycline	1	Doramectin	1			Tilmicosin	2			Neomycin	1
Piperonyl butoxide	1	Enrofloxacin	1			Ketoprofen	1			Pirlimycin	1
Sulfamethoxypyridazine	1	Moxidectin	1			Piperonyl butoxide	1			Spectinomycin	1
Total	286	Total	214	Total	218	Total	181	Total	195	Total	152

Note: The above analytes were collected from dairy cows only. The total analytes (violative and non‐violative) detected during each year are: 2021: 504 detected dairy analytes, 2022: 401 analytes, and 2023: 359 analytes.

4. Discussion

This study highlights significant patterns in veterinary drug residue detections in cattle from 2021 to 2023. Across FSIS residue testing in solid tissues from all food animal commodities, over 92% of positive residue detections occurred in cattle tissues. According to the FDA, the ten most frequently detected drugs responsible for illegal residues in meat derived from treated animals (based on USDA/FSIS data from 2015 to 2019) were respectively: desfuroylceftiofur, penicillin, sulfadimethoxine, flunixin, sulfamethazine, neomycin, florfenicol, tilmicosin, ampicillin, and gentamycin sulphate (U.S. Food and Drug Administration 2023). Notably, all ten of these drugs were also identified among the top 20 violative residues in cattle observed in USDA/FSIS data from 2021 to 2023, with nine of them ranking within the top 10. This consistent pattern across different timeframes highlights the ongoing challenges associated with the use and management of these specific veterinary drugs in food‐producing animals.

Dairy cows and bob veal stood out as particularly high‐risk groups for drug residue violations. The higher number of residue detections observed in dairy cattle may reflect either greater sampling intensity or higher underlying residue prevalence. The elevated detection levels in dairy cattle could also suggest persistent challenges in ensuring adherence to drug withdrawal periods, potentially due to more frequent therapeutic use. Similarly, bob veal exhibited notably high violative detections, highlighting possible gaps in treatment protocols or oversight within veal production systems. These trends point to the need for enhanced monitoring and compliance strategies targeted toward these specific subpopulations. Nevertheless, the predominance of antibiotics among the most frequently detected residues raises significant public health concerns. This pattern is particularly alarming given the global threat of antimicrobial resistance (AMR), as drug residues in the food supply may contribute to the development of resistant bacterial genes in humans. The continued detection of multiple drug classes also reflects the complexity of residue control and the need for more tailored risk management strategies.

Figure 2 highlights the top 10 violative and non‐violative residues detected in cattle during 2021, 2022, and 2023. Desfuroylceftiofur, a metabolite of ceftiofur, an antibiotic commonly used in cattle to treat infections, was the top violative residue. Penicillin's continued appearance among top violative residues is especially concerning due to its known allergenic potential and regulatory sensitivity (Baynes et al. 2016). Flunixin, a widely used anti‐inflammatory, also remains problematic which highlights the need for stricter compliance practices for drugs with various therapeutic purposes. Despite existing regulations, a narrow group of commonly used drugs continues to account for most violations. This repeated pattern indicates that mitigation strategies may need to be reevaluated and reinforced, particularly for high‐risk drug categories.

FIGURE 2.

Top 10 violative vs. top 10 non‐violative cattle residues. This plot compares the count of violative and non‐violative cattle residues based on analyte counts. Some analytes have overlapping values, resulting in fewer than 10 analytes in each category.

Among detected residues that were not above violative levels, these findings remained within acceptable regulatory limits; however, their high detections warrant further consideration. Frequent non‐violative detections, such as tulathromycin, raise questions related to repeated low‐level dietary exposure over time, which warrants further investigation regarding potential long‐term dietary exposure (Figure 2). This consideration is particularly relevant in the case of long‐acting antiparasitic drugs like eprinomectin where residues can persist at low levels for extended periods. Additionally, frequent detections near established tolerances require further evaluation to determine whether they reflect marginal compliance with established withdrawal periods. Also, the overlap between some violative and non‐violative residues during the years 2021, 2022, and 2023 points to potential inconsistencies in dosage and label adherence, incomplete withdrawal, or variability in residue persistence which may warrant a reevaluation of current maximum residue limits (MRLs) and withdrawal periods.

It is important to note that the dataset only includes samples that tested positive for drug residues, without providing information on the total number of animals sampled. This limits the ability to interpret the true prevalence of drug residue violations across the cattle population. In particular, the dataset does not provide information on the total number of samples analysed per drug, nor does it distinguish between the NRP surveillance samples and inspector‐generated samples, limiting the ability to evaluate differences in residue prevalence across sampling frameworks. Accordingly, the findings should be interpreted as descriptive of detection patterns rather than as indicators of residue prevalence or compliance performance. These results may help inform future evaluations of residue monitoring priorities, while recognising the limitations of the available data. Regulatory agencies should also consider narrowing their surveillance and enforcement strategies to focus on a small group of high‐risk drugs and animal classes such as the case of cattle. Incorporating denominator‐based data, residue concentration distributions, and clearer differentiation between sampling types would improve the ability to assess residue prevalence, compliance, and risk. Several approaches can also be implemented to enhance residue control in cattle including educational outreach on label and drug withdrawal times, improved recordkeeping, extensive pharmaceutical studies on high‐risk drugs, and investment in rapid on‐site testing to help mitigate the recurrence of violative and non‐violative residues. Besides, the consistency of these findings over multiple years reinforces the need for comprehensive data analysis based on trends in previous years to control drug residues, support sustainable livestock production, and protect public health.

5. Conclusion

This study highlights significant trends in US veterinary drug residue monitoring during the years 2021, 2022, and 2023 across various cattle types with dairy cows having the most detections (41%) followed by beef cows (16%) and bob veal (14%). Among the most frequently detected residues, antibiotics dominated the list with a consistent group of drugs being responsible for the majority of violative and non‐violative detections. Besides antibiotics, the list of the top 20 residues detected included anti‐inflammatory drugs, antiparasitic agents, and growth promoters. The data revealed consistent patterns in the detection of various drug residues. Desfuroylceftiofur consistently remained the most commonly detected violative analyte in cattle each year with frequent detections also observed for penicillin, flunixin, sulfadimethoxine, sulfamethazine, florfenicol, neomycin, and tilmicosin. These findings underscore the importance of addressing the persistent presence of certain veterinary drugs in cattle products. The results of this study can help inform the prioritisation of analytes and cattle types in future sampling plans and risk‐based monitoring strategies. Continued monitoring of commonly detected residues, especially in dairy cows, can support regulatory agencies in refining withdrawal times, improving compliance, and reducing violative levels in the food supply. Moreover, the identification of residue trends over multiple years provides a valuable framework for guiding educational outreach, producer practices, and national residue control programs aimed at enhancing food safety and public health. Future research should incorporate denominator‐based sampling data and residue concentration distributions to better assess prevalence, compliance, and risk. Regional analyses within the United States may help identify geographic variation in residue detection patterns and inform targeted interventions. In addition, similar multi‐year analyses using residue monitoring data from other countries could provide valuable international context and support harmonisation of residue control strategies.

Author Contributions

Abdullah Alwahaimed: Methodology, validation, visualisation, writing – review & editing, software, formal analysis, project administration, investigation, writing – original draft, and conceptualisation. Joesph Eifert: Supervision, resources, writing – review & editing, validation, visualisation, methodology, conceptualisation, and project administration. All authors have read and approved the final manuscript.

Funding

The authors have nothing to report.

Ethics Statement

This study did not involve the use of live animals or human participants and therefore did not require ethical approval.

Conflicts of Interest

The authors declare that there are no financial, professional, or personal conflicts of interest that could have influenced the work reported in this study. All interpretations and conclusions presented are based solely on the data and analyses conducted by the authors, without any bias or external influence.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request. Every effort will be made to provide access to relevant datasets and supporting materials as needed for verification or replication purposes.