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Davy JS, Forero LC, Strickler S, Gillespie J, Maier GU. Comparison of deworming strategies for pre-weaned beef calves. Vet Parasitol 2023; 322:110005. [PMID: 37729829 DOI: 10.1016/j.vetpar.2023.110005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 09/22/2023]
Abstract
While anthelmintic treatment in young calves at first vaccination has not proven repeatedly effective in improving weight gain, there is evidence that treatment 90Â day prior to weaning can enhance weight gain. This is difficult in most California cow/calf operations as after initial vaccination, calves are not again handled until preconditioning just prior to weaning. In an attempt to increase weight gain without the need for anthelmintic retreatment prior to preconditioning, 130 cow/calf pairs were stratified and assigned to three treatments of eprinomectin extended release injection (150 d efficacy), doramectin conventional injection, and an untreated control. Dams and calves received the same treatment. All treatments were commingled on irrigated pasture in Northern California. Sampling included weight (d 0, 75, and 145), fecal parasite (d 0, 14, 75, and 145), cow body condition score (d 0, 75, and 145), and cow pregnancy detection (days bred). Calf weight gain was not impacted by anthelmintic treatment (PÂ =Â 0.44). However, cow weight gain was impacted by treatment (PÂ <Â 0.01), with eprinomectin extended release showing higher weight gain than both doramectin conventional and the control (ADG kg 0.29, 0.23, 0.22, respectively). Cow weight gain differences were expressed greater toward the end of the trial than early on. Fecal egg count sampling failed to explain the difference in cow weight gain. Cow body condition score (PÂ =Â 0.15) and days bred (PÂ =Â 0.50) were not significantly affected by treatment. Although cow weight gain increased with an extended release anthelmintic treatment, this effect did not seem to be evident in suckling calves on high quality irrigated pastures in Northern California when compared to a conventional injectable and control treatments. Neither anthelmintic treatment appeared beneficial over a control when administered to suckling calves during initial vaccination at approximately 90 days of age.
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Affiliation(s)
- Josh S Davy
- UC Livestock and Range Advisor Tehama, Glenn, Colusa, 1754 Walnut St, Red Bluff, CA, USA.
| | - Larry C Forero
- UC Livestock and Range Advisor Shasta, Trinity, 1851 Hartnell Avenue, Redding, CA 96002, USA.
| | - Shane Strickler
- Boehringer Ingelheim Animal Health, 3239 Satellite Blvd NW, Duluth, GA 30096, USA.
| | - Joe Gillespie
- Boehringer Ingelheim Animal Health, 3239 Satellite Blvd NW, Duluth, GA 30096, USA.
| | - Gabriele U Maier
- School of Veterinary Medicine, One Shields Avenue, Davis, CA 95616, USA.
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2
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Ding H, Ao C, Zhang X. Potential use of garlic products in ruminant feeding: A review. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2023; 14:343-355. [PMID: 37635929 PMCID: PMC10448032 DOI: 10.1016/j.aninu.2023.04.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 01/23/2023] [Accepted: 04/06/2023] [Indexed: 08/29/2023]
Abstract
The addition of antibiotics as growth promoters to ruminant feed can result in bacterial resistance and antibiotic residues in ruminant products. Correspondingly, there is serious public concern regarding the presence of antibiotic residue in ruminant products and the consequent threat to human health. As a result, the addition of plants and their products to ruminant feeds, as an alternative to antibiotics, has received much attention recently. Garlic and its products are rich in organosulphur compounds, which have a variety of biological activities and have been widely used as natural additives in animal production. This review presents recent knowledge on the addition of garlic products (powder, skin, oil, leaf and extracts) to the diets of ruminants. In this paper, garlic products are evaluated with respect to their chemical composition, bioactive compounds, and their impacts on the rumen ecosystem, antioxidant status, immune response, parasitic infection, growth performance and product quality of ruminants. This review provides valuable guidance and a theoretical basis for the development of garlic products as green, highly efficient and safe additives, with the aims of promoting ruminant growth and health, reducing methane emissions and improving ruminant product quality. Garlic extracts have the potential to control parasite infections by decreasing the faecal egg count. Garlic powder, oil and allicin are able to reduce the methane emissions of ruminants. Organosulphur compounds such as allicin, which is present in garlic products, have the potential to inhibit membrane lipid synthesis of the archaeal community, thus influencing the population of methanogenic archaea and resulting in a reduction in methane emissions. Some garlic products are also able to increase the average daily gain (garlic skin, water extract, and leaf) and the feed conversion ratio (garlic skin and leaf) of ruminants. Garlic stalk silage fed to sheep has the potential to improve the nutritional value of mutton by increasing the concentrations of linoleic and linolenic acids and essential amino acids. Sheep fed a diet containing garlic powder or oil are able to produce milk with higher concentrations of the conjugated linoleic acids and n-3 fatty acids, which has health benefits for consumers, due to the widely recognized positive impact of n-3 polyunsaturated fatty acids and conjugated linoleic acids on human heart health, improving platelet aggregation, vasodilation and thrombotic tendency. Overall, garlic products have the potential to enhance growth performance and product quality and reduce parasite infections, as well as methane emissions of ruminants.
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Affiliation(s)
- He Ding
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Changjin Ao
- Key Laboratory of Animal Feed and Nutrition of Inner Mongolia Autonomous Region, College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xiaoqing Zhang
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
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3
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Hamel D, Kunkle BN, Liebstein M, Bader J, Shryock J, Visser M, Yoon S, Fankhauser B, Rehbein S. Eprinomectin 5% w/v extended-release injection for the treatment of larval and/or adult Bunostomum phlebotomum, Haemonchus contortus, H. placei, Nematodirus helvetianus, Oesophagostomum radiatum, and Trichostrongylus colubriformis infections in cattle. Parasitol Res 2022; 121:2173-2178. [PMID: 35503138 DOI: 10.1007/s00436-022-07529-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 04/24/2022] [Indexed: 11/24/2022]
Abstract
In an effort to generate data for regulatory purposes on the therapeutic efficacy of eprinomectin 5% w/v extended-release injection (Eprinomectin ERI) (LongRange®, Boehringer Ingelheim) against infections of immature and adult stages of some nematode species (or stages) which are generally less common or predominantly seen in younger cattle, nine studies (minimum two per parasite and stage) were conducted in the USA and Germany. A total of 218 young cattle were included in seven experimentally induced infection studies (180 animals) and two studies with naturally acquired nematode infections (38 animals), which were compliant with WAAVP and VICH guidelines. In each study, cattle were randomly assigned into groups which received 1 mL per 50 kg body weight of either saline (controls) or Eprinomectin ERI (equivalent to 1 mg eprinomectin per kg body weight) via subcutaneous injection when the parasites were developing fourth-stage larval (L4) or adult nematodes. Following necropsy and parasite recovery, percentage efficacy was calculated based on the comparison of geometric mean nematode counts of the Eprinomectin ERI- vs. the saline-treated animals. Eprinomectin ERI-treated cattle had significantly (p < 0.05) lower counts of each species and stage of nematodes than the controls. Eprinomectin ERI treatment was demonstrated to be efficacious (> 90%) against L4 and adult Bunostomum phlebotomum and Nematodirus helvetianus; against L4 Haemonchus placei, Oesophagostomum radiatum, and Trichostrongylus colubriformis; and against adult H. contortus. Percentage efficacy against L4 H. contortus was variable (69.6 to 100%). All treatments were well accepted, and no treatment-related health problems were observed in any study.
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Affiliation(s)
- Dietmar Hamel
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany.
| | - Bruce N Kunkle
- Boehringer Ingelheim Animal Health USA Inc., Missouri Research Center, 6498 Jade Road, Fulton, MO, 65251, USA
| | - Martin Liebstein
- Boehringer Ingelheim Animal Health USA Inc., Missouri Research Center, 6498 Jade Road, Fulton, MO, 65251, USA
| | - Jonathan Bader
- Boehringer Ingelheim Animal Health USA Inc., Missouri Research Center, 6498 Jade Road, Fulton, MO, 65251, USA
| | - Jeffrey Shryock
- Boehringer Ingelheim Animal Health USA Inc., Missouri Research Center, 6498 Jade Road, Fulton, MO, 65251, USA
| | - Martin Visser
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany
| | - Stephen Yoon
- Boehringer Ingelheim Animal Health USA Inc., 3239 Satellite Boulevard, Duluth, GA, 30096-4640, USA
| | - Becky Fankhauser
- Boehringer Ingelheim Animal Health USA Inc., 3239 Satellite Boulevard, Duluth, GA, 30096-4640, USA
| | - Steffen Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany
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Padivitage N, Wang L, Wimalasinghe RM, Rustum AM. Development and Validation of a Stability-Indicating RP-HPLC Method for Determination of Eprinomectin, its Degradation Products, and Butylated Hydroxytoluene in a Pour-On Finished Product. Chromatographia 2021. [DOI: 10.1007/s10337-021-04082-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Maier G, Doan B, O'Connor AM. The Role of Environmental Factors in the Epidemiology of Infectious Bovine Keratoconjunctivitis. Vet Clin North Am Food Anim Pract 2021; 37:309-320. [PMID: 34049661 DOI: 10.1016/j.cvfa.2021.03.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Environmental factors that contribute to the pathogenesis of infectious bovine keratoconjunctivitis (IBK) include face flies, ultraviolet (UV) radiation, and mechanical irritation from plant awns or dust. Limited research has shown face fly control to be associated with lower incidence of IBK. UV radiation is known to cause corneal irritation and damage in mammalian species. The increased formation of corneal dark cells has been observed following UV radiation in exposed calves. Moraxella bovis preferentially binds to corneal dark cells where it can be found in pits, which may be formed due to bacterial contact. Little is known about the efficacy of management of pasture plants on the prevention of IBK.
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Affiliation(s)
- Gabriele Maier
- Department of Population Health and Reproduction, School of Veterinary Medicine, Davis, 1 Shields Avenue, VM3B, Davis, CA 95616, USA.
| | - Binh Doan
- Carver College of Medicine, University of Iowa, 51 Newton Road, 1-400 BSB, Iowa City, IA 52242, USA
| | - Annette M O'Connor
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, Room G-100, East Lansing, MI 48824, USA
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Kasimanickam RK, Kasimanickam VR. Association of gastrointestinal parasite burden, serum cytokines and hormones concentrations, and pregnancy in Angus-cross beef cows. Vet Parasitol 2021; 295:109464. [PMID: 34051524 DOI: 10.1016/j.vetpar.2021.109464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 05/08/2021] [Accepted: 05/11/2021] [Indexed: 12/18/2022]
Abstract
The objective was to elucidate the relationships among gastrointestinal (GI) parasite load, serum cytokines (Th 1 - Interleukin (IL) 2, Interferon (IFN) γ and Tumor necrosis factor (TNF) α; Th 2- IL4, IL6, and IL10) levels, hormones (progesterone, cortisol, 8-epi-prostaglandin F2 alpha (isoprostane), prolactin, substance-p, and prostaglandin F metabolites) concentrations, and pregnancy in beef cattle. Angus-cross beef cows (n = 700; age, 3-8 y) were blocked by age and body condition score (BCS, 1-9), and were randomly assigned to treatment (n = 350, TRT, 50 mg of eprinomectin/50 kg BW, im) or control (n = 350, CON, no treatment) on Day -30. Cows were synchronized using Controlled Internal Drug Release insert (CIDR) + CO-Synch protocol and artificially inseminated at a fixed time on Day 0 (66 h after CIDR removal). Fecal samples were collected to determine fecal egg count per gram (FEG, McMaster method) on Days -30, -23, -16, -7, 7, 0, 16 and 23, and blood samples were collected on Days -7, 0, 7, 16 and 23. Serum cytokines were determined on Days -7, 0, 7, 16 and 23, and circulating hormones were measured on Day 16. BCS were recorded on Day 16 following artificial insemination (AI), and pregnancy status was diagnosed on Day 30 and 60. Pregnancy/AI varied among treatment groups on Day 30 [TRT, 62.0% (217/350); CON, 54.9% (192/350) (P = 0.05)] and Day 60 [TRT, 60.9% (213/350); CON, 51.7% (181/350) (P < 0.05)]. Pregnancy loss between 30 and 60 days for TRT and CON groups were 1.8% (4/217) and 5.7% (11/192), respectively (P < 0.05). The BCS on Day 16 did not differ among treatment groups (P> 0.1). Four groups of 40 cows were selected based on their pregnancy status and treatment: pregnant, TRT; non-pregnant, TRT; pregnant, CON; and non-pregnant, CON to compare the mean FEG, cytokines, and hormones levels. The FEG and cytokine concentrations were significantly (P < 0.05) influenced by treatment, pregnancy status, day, treatment by pregnancy status, and treatment by day. Day 16 hormone concentrations were considerably influenced by treatment, pregnancy status, and treatment by pregnancy. Although FEG on Day -30 did not differ among the groups (P> 0.1), it was lower in treated, pregnant cows compared with cows in other three groups from Day -23 onwards (P < 0.05). Overall and pairwise comparisons showed that serum concentrations of Type 1 cytokines, IL2, IFNγ, and TNFα were lower (P < 0.05) from gestational Day 7 onwards in treated, pregnant cows compared with cows in other three groups. In contrast, serum concentrations of Type 2 cytokines, IL4, IL6 and IL10 were greater (P < 0.05) from gestational Day 7 onwards in treated, pregnant cows compared with cows in other groups. Serum concentrations of progesterone was greater and other hormones were lower for pregnant cows in TRT group compared to cows in other groups on gestational Day 16. In conclusion, GI parasite load was reduced; Th 1 cytokines levels were decreased; Th 2 cytokines concentrations were increased; progesterone level was increased; and cortisol, substance-P, prolactin, isoprostane, and PGFM were decreased in pregnant, TRT cows. These changes also resulted in an increase in P/AI. It is plausible that direct and bidirectional host-parasite interactions mediated by cytokines and hormones may have promoted maternal tolerance of an immunologically diverse conceptus and the establishment of pregnancy.
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Affiliation(s)
- Ramanathan K Kasimanickam
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164, USA.
| | - Vanmathy R Kasimanickam
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164, USA; AARVEE Animal Biotech LLC, Corvallis, OR, 97333, USA.
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7
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Johnson J, Kasimanickam VR, Kastelic JP, Kasimanickam RK. Reduced gastrointestinal worm burden following long term parasite control improves body condition and fertility in beef cows. Vet Parasitol 2020; 287:109259. [PMID: 33035775 DOI: 10.1016/j.vetpar.2020.109259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 09/26/2020] [Accepted: 09/27/2020] [Indexed: 01/10/2023]
Abstract
The objective of this study was to compare effects of gastrointestinal parasite control over a long vs short term (PC-LT vs. PC-ST) on fecal parasite load, body condition and pregnancy in beef cows. On Day 0, fecal samples were collected from Angus cross cows (n = 1462) and they were assigned a body condition score (BCS: 1, emaciated; 9, Obese) and randomly divided into two groups (within location) to receive extended-release eprinomectin [PC-LT; n = 749; 50 mg/50 kg body weight (BW)] or pour-on ivermectin (PC-ST; n = 713; 25 mg/50 kg BW). All cows were synchronized with CO-Synch + CIDR [100 μg GnRH + progesterone vaginal insert (CIDR) application on Day 20, CIDR removal +25 mg PGF2a on Day 27, and artificial insemination +100 μg GnRH on Day 30 (66 h after CIDR removal)] protocol, artificially inseminated (AI; Day 30) and on Day 44, exposed to breeding bulls (1:40 bull to cow ratio) for the remainder of the 85 day breeding season. On Day 90, a second fecal sample was collected from all cows and the cows were examined to determine pregnancy/AI (P/AI). All cows were assigned a BCS on Day 180 and re-examined to determine pregnancy/breeding season (P/BS). Worm egg count per gram of feces (FEG) was determined by McMaster method. There were no differences (P > 0.1) between PC-LT and PC-ST groups on Day 0 for FEG (46.9 ± 13.1 vs 42.6 ± 15.2, respectively; mean ± SEM) or BCS (5.95 ± 0.12 vs 6.00 ± 0.20). The mean FEG (PC-LT, 12.3 ± 4.7 vs. PC-ST, 131.3 ± 10.9) on Day 90 and BCS (PC-LT, 6.04 ± 0.07 vs. PC-ST, 5.79 ± 0.13) on Day 180 differed (P < 0.05) between the two groups. Mean P/AI [PC-LT, 62.9 %; (471/749) vs PC-ST, 57.4 %; (409/713)] and P/BS [PC-LT, 92.9 % (696/749) vs PC-ST, 90.0 (642/713)] also differed (P < 0.05). Lower FEG at Day 90 resulted in moderate to good body condition at Day 180 and cows with moderate to good body condition at Day 180 had higher P/BS. In conclusion, lower worm burden with long-term parasite control reduced FEG and improved BCS, P/AI and P/BS.
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Affiliation(s)
- Jerimyah Johnson
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
| | - Vanmathy R Kasimanickam
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
| | - John P Kastelic
- Department of Production Animal Health, University of Calgary, Faculty of Veterinary Medicine, Calgary, AB, Canada.
| | - Ramanathan K Kasimanickam
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
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Efficacy and production benefits following use of eprinomectin extended-release injection in pastured dairy heifers. Vet Parasitol 2020; 282:109157. [PMID: 32497935 DOI: 10.1016/j.vetpar.2020.109157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/24/2020] [Accepted: 05/25/2020] [Indexed: 11/20/2022]
Abstract
A study was conducted in grazing dairy heifers to assess anthelmintic efficacy and production responses in dairy heifers treated with a single injection of eprinomectin in an extended-release formulation over a 123 day-period. The study was conducted on a pasture-based dairy in the Southeastern United States (North Carolina) over the summer months. Sixty crossbred dairy heifers were weighed and randomly allocated into 2 groups. One group (n = 30) was given 5% eprinomectin subcutaneously in the cervical region while the other group (n = 30) was given an equivalent volume of saline. Calves were weighed every 30 days throughout the trial for calculation of average daily gain and differences in overall weight gain. In addition, fecal samples were collected at days 0, 30, 60, 90 and 123 for worm egg count and coproculture. Both groups of cattle had similar worm egg concentrations at the start of the study. However, the control group had increasing concentrations of fecal worm eggs throughout the summer months while the heifers that received eprinomectin had minimal fecal worm eggs. The primary parasite species identified in this study were Haemonchus placei, Cooperia species and Ostertagia. The heifers that received eprinomectin gained 105 + 2.8 kg during the 123-day study period, representing an average daily gain of 0.85 kg/day compared to 78.3 + 4.1 kg (0.64 kg/day) for the control group. This represented a 33 % increase in average daily gain associated with deworming. The results of this study indicate that a single dose of extended-release eprinomectin was sufficient to control parasites through a 123-day summer grazing season and that administration of the anthelmintic had a significant impact on weight gain.
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Volk MJ, Krause TR, Stokes RS, Ireland FA, Shike DW. Effects of extended-release eprinomectin on fescue toxicosis, performance, and reproduction on fall-calving beef cows. Transl Anim Sci 2019; 3:1423-1434. [PMID: 32704907 PMCID: PMC7200507 DOI: 10.1093/tas/txz093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 06/12/2019] [Indexed: 11/14/2022] Open
Abstract
The objective of this experiment was to evaluate effects of extended-release eprinomectin on fescue toxicosis and impacts on performance and reproduction in fall-calving beef cows. Fall-calving Angus × Simmental multiparous cows [n = 335; age = 5.8 ± 2.1 yr; 586.5 ± 6.0 kg body weight (BW); 5.48 ± 0.05 body condition score (BCS)] were stratified by BW, age, and BCS and randomly assigned to one of three treatments. Treatments included a spring injection of extended-release eprinomectin (SERE) on day 0, a fall injection of extended-release eprinomectin injection (FERE) on day 84, and a saline control (CON). All treatments were administered at a rate of 1 mL/50 kg BW. Prior to the experiment, all cows were treated with oral fenbendazole to minimize parasite load. Cows grazed endophyte-infected tall fescue. Hair coat score (HCS), BW, and BCS were recorded on all cattle. Fecal egg count (FEC), respiration rate (RR), horn fly and tick count, hematocrit (% packed cell volume, PCV), and serum prolactin were analyzed on a subset of cows (35/treatment). On day 194, cows were artificially inseminated (AI) and 11 d following AI were exposed to bulls for 51 d. Milk production was estimated on day 210 on a subset of 85 cow-calf pairs (28-29/treatment). There was a tendency for a treatment × time interaction (P = 0.07) for FEC likely driven by an increase in FEC of the CON cattle at day 126 compared to SERE and FERE. There was a tendency for a treatment × time interaction (P = 0.06) for cow BW, largely driven by time differences; however, there was no effect of treatment (P = 0.84) on BW. There was no difference (P ≥ 0.13) in cow PCV, fly and tick count, BCS, HCS, RR, and serum prolactin throughout the experiment. Additionally, there was no difference (P ≥ 0.46) in Julian calving date, calf birth BW, or milk production between treatments. Interestingly, heifer calves born to FERE dams tended to have greater (P = 0.06) weaning BW compared to heifer calves born to CON dams. In addition, there was no difference (P ≥ 0.17) in heat patch scores, AI conception rates, or overall pregnancy rates between treatments. Extended-release eprinomectin did not impact cow growth performance, reproductive performance or fescue toxicity symptoms when grazing endophyte-infected tall fescue; however, calf weaning BW tended to be improved.
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Affiliation(s)
- Mareah J Volk
- Department of Animal Sciences, University of Illinois, Urbana
| | - Taylor R Krause
- Department of Animal Sciences, University of Illinois, Urbana
| | | | - Frank A Ireland
- Department of Animal Sciences, University of Illinois, Urbana
| | - Daniel W Shike
- Department of Animal Sciences, University of Illinois, Urbana
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