Don’t let internal parasites affect performance! CATTLE U Marc Campbell DVM Bayer AH VSL July 31, 2019 /// Bayer 16:9 Template 2010 /// November 2017

Parasites of Cattle Arthropods (Flies, Ticks, etc) Protozoa (Coccidia) Cestodes (Tapeworms) Trematodes (Flukes) And………….Nematodes (WORMS!!)

Estimated Losses in U.S. Cattle due to Parasites Horn Flies $1.36 billion Stable Flies $672 million Horse Flies $296 million Face Flies $191 million Ticks $162 million Mosquitoes $78 million Lice $59 million NEMATODES (Worms) $2 BILLION Based on Kunz et al 1991 and adjusted for inflation rates

Ideal environment for larval development 40-90 degrees F (50-90 most) Optimum temperature is 70-80 degrees F High humidity is best Best transmission times are Spring and Fall

Nematode Life Cycle (Circle of Life)

Nematode Life Cycle

Fecundity of Adult Nematodes Ostertagia- 300 eggs per day Haemonchus- 5,000-10,000 eggs per day Cooperia- 1,000-3,000 eggs per day Nematodirus- 50-100 eggs per day

Gastrointestinal Nematodes Eggs Hatch in 2-3 days Cold temperatures delay development Desiccation most detrimental

Gastrointestinal Nematodes Larvae L1, L2 - feed in manure pat

L3 Nematode Quest (horizontal and vertical) -5 cm vertical and about 20cm horizontal 80% of parasites can be found below 5cm Rainfall and dung dwelling creatures can increase radius greatly Cattle usually won’t graze within 18 inches of fecal pats

L3 Nematode Can also undergo a phenomenon known as “Anhydrobiosis” This is a dormant state induced by drought or cold in which an organism becomes almost completely dehydrated and reduces its metabolic activity This can happen up to 7 times (this is why parasite burdens can be worse after an extended drought!)

Parasite Management Effort and Focus Parasite treatment (fall deworming) Targets 10% of the parasite population Parasite management & prevention (strategic or spring deworming) Targets 90% of the parasite population “There are two general approaches to minimize losses caused by cattle worms: First, we can treat worm problems during fall; this approach only eliminates the worms that are in the calves and cows as they are coming off the pasture. It does not prevent the losses that occur while they’re on the pasture, and it only eliminates approximately 10% of the worm population owned by the producer (only 10% of the population are in the animals at any time; the rest are living in the pasture). It can, however, reduce the cost of “housing” these nematodes over the winter in these animals. Or, the other approach is to develop a strategic deworming program that targets both the 10% of the worms in the animals and the 90% present as eggs or juveniles in the pastures. This strategic program can prevent the losses that occur on the pastures and the losses that occur during the winter.” Hildreth AVC presentation 12/08

Internal Parasite Predilection Sites

Relative Importance of Cattle Worms How Common Relative Pathogenicity Cooperia Ostertagia Oesophagostomum Strongyloides Haemonchus Trichostrongylus Nematodirus Dictyocaulus Trichuris Bunostomum 14 14

Ostertagia Causes Anorexia

Sub Clinical Parasitism Diarrhea Bottle jaw Anemia Rough hair coat Sub Clinical Parasitism Reduced milk production Reduced Reproductive performance Reduced Milk Quality Increased susceptibility to disease Reduced growth rate Reduced weaning weight

Deworming is the most valuable tool to cow/calf producers Parasite losses are usually subclinical (not seen externally)

Figure 1. Relative weights of clean sections of the sheep GI Tract by state of parasite challenge (Jacobson et al, 2009. Vet. Parasit. 161:248-254)

5 Cardinal Signs of Inflammation Heat Redness Swelling Pain LOSS OF Function!!

The Impact on Immunity Parasites compromise the immune system. Parasites “create” an immune response. Resulting in profound immune system changes.4 Parasites turn off some immunological function. That means a parasitized animal can’t mount an appropriate response to a health challenge, and vaccinating that animal may be less effective.”4 4Gasbarre L. Effects of gastrointestinal nematodes on the bovine immune system. Veterinary Parasitology. 1997:72(3-4):327-337.

Controlling Worms While Grazing “Helps” with Diseases While Feeding Smith, R.A. et al, 2000. FBZ during pasture on days 0, 28 and 56. FBZ at feedlot on day 118

Can Parasites Effect Milk Production?

Milk Production. Results Increase in milk production of 2.07 lbs./day In a recent study, even eliminating low (sub-clinical) parasite burdens in lactating cows produced a consistent increase in milk production.* This study included 28 herds and 954 cows in Canada. Results Increase in milk production of 2.07 lbs./day Immediate drop in egg counts that lasted at least 100 days Return on investment on more than 7:1 *Data on file

Reproductive Benefits of Deworming?

Average of a 12% Increase in Conception Rate Reproduction 97% vs 85% the first year 91% vs 78% the second year Average of a 12% Increase in Conception Rate

Manage Cows for Reproduction Length of Calving Season 140 Days 60 Days Calves Born in Number Weight 1st 20 days 25 540 50 2nd 20 days 22 510 30 3rd 20 days 18 480 20 4th 20 days 12 450 ---- 5th 20 days 10 420 6th 20 days 8 390 7th 20 days 5 360 Overall 100 478 lbs. 519 lbs. This slide shows the impact of having cows breeding late and ultimately calving late. Most operations have a few cows with late calves. In this example, 65% of the calves are born in the first 60 days. It’s not unheard of for 65% of the calves to be born in the first 20 days in herds that are managing the cows for reproduction. Wiltbank 1961

Nutrient Priorities in Cattle

Energy/Lactation Cycle Energy (mcal/day) Dry off Lactation trimester *Coppock: Vet Med 1990 Parturition Energy for milk + maintenance Body energy stores Feed energy This graph shows the energy needs for milk and body maintenance, the feed short fall and the loss of body energy stores that take place at peak lactation. This peak lactation comes approximately 85 days post calving. If a cow is to cycle and settle to have a calf the same time next year as this year, she has to stabilize her bodyweight right at peak lactation. It’s at this point where anything that affects the cow’s ability to stabilize her weight will affect her ability to cycle and settle. This is where even a small parasite burden can affect conception. Parasites, by their very presence, affect the cow’s immune system. In effect, the cow has her immune system constantly revved up. The cow’s immune system recognizes that parasites are present, but it can’t get rid of them. The immune system keeps trying and trying, setting up a cascade of events that results in a suppressed appetite. 1 2 3

Parasitism Has a Lasting Impact Deworming improves the onset of puberty and may increase later milk production1 Lost weight-gain due to parasitism in the first grazing season persisted in subsequent seasons2 1 Perri, Gastrointestinal parasite control during prepuberty improves mammary parenchyma development in Holstein heifers, Vet Parasitol. 2013 Dec 6;198(3-4):345-50 2Larssonet al.(2011), Parasite control in pasture-grazed dairy cattle: Are we at the edge of a precipice?. Available from: https://www.researchgate.net/publication/279216938/download Lifetime productivity of females starts from the onset of puberty Influenced by subsequent events like age at first calving Product of prepartum nutrition, reflected through body condition score (BCS) Diskina, Theriogenology, Managing the reproductive performance of beef cows, Volume 86, Issue 1, 1 July 2016, Pages 379-387 Parasites in first year or two of a heifer’s life may have lasting impacts on future productivity in the herd Charlieret al. 2009 Parasite losses may include reduced milk production; lower weaning weights; delayed puberty and decreased fertility in replacement heifers; lower pregnancy rates in mature cows; and reduced feed intake, reduced feed efficiency and immune suppression in all classes of cattle. Internal Parasite Control in Beef Cattle, Revised by Lee Jones, Assistant Professor and Veterinary Field Investigator, UGA College of Veterinary Medicine Original manuscript by James E. Strickland, Retired Extension Veterinarian, 2012

Evaluation of long-acting moxidectin and ivermectin in the development of replacement beef heifers 1. Started with “the best” weaned replacement Angus 2. Cydectin LA, Ivomec +, Control 3. Grew them, bred them, calved them out, and then weaned their calves

Strongyle EPG (GM) Treatments Applied

Gain summary (lbs, LSM) d 0 - 433 Treatment Group Mean Total Gain Mean ADG % Improvement over Control Cydectin® LA 520a 1.21a 10% Ivomec® Plus 502a 1.17a 6.5% Control 469b 1.08b --         a,b Means in same column with unlike superscripts are significantly different (P < 0.05)

% Pregnant at 63 days

Calf Performance (lbs.) Initial Treatment Groups Cydectin® LA Ivomec® Plus Control P value (Pr > F) Birth Wt. 66.4 65.3 61.5 0.36 Adj. Weaning Wt. 482a 468ab 439b 0.016 ADG (lbs/day) 1.74a 1.66ab 1.57b

1. Farm A & B “Parasite Profiles”: Farm Profile A · History of routine parasiticide Rx · Low stocking rates · Improved pastures · Low egg counts from calves B · No routine anthelmintic practice · High stocking rates · No pasture (weed) improvements · High egg counts from calves

Study design: Calve out all cows (130 and 33 pairs [farms A + B]) Treat every other mother cow (within 2 weeks of calving) Weigh calves at treatment day Weigh calves 90 days later Periodic egg counts

Cow-calf, mother cow treatment 90-day BW gains of Rx-cow calves over control-cow calves Farm A (Low Worm) Farm B (High Worm) 38

Generic vs branded comparison

Study design 6 groups of calves with 7 in each group Branded IVOMEC, 4 generics and one negative control Trial lasted 56 days Cattle were grazed as one group on 45 acre heavily contaminated pasture Measured FECR with coproculture and ADG instead of just FECR

Results

Results in ADG of each treatment group Product Used Average Daily Gain in pounds/day Cooper MEC 1.21 Ivermectin Pour-On 1.28 Top Line 1.30 Negative Control IVERCIDE 1.36 IVOMEC 1.42

Milligrams per kilogram of body weight Year of Introduction of Anthelmintic Compounds 1000 100 10 1 0.1 1940 1950 1960 1970 1980 1990 2000 Year of Introduction phenothiazine organophosphates Milligrams per kilogram of body weight thiabendazole pyrantel morantel tetramisole levamisole oxfendazole doramectin abamectin eprinomectin ivermectin moxidectin

Three Primary Drug Families Benzimidazoles Fenbendazole Albendazole Oxybendazole Nicotinics Levamisole Morantel Pyrantel Macrocyclic Lactones Ivermectin Doramectin Moxidectin Eprinomectin

The “trail” from allo-grooming after topical parasiticides (Bouquet-Melou et al. 2004. Int. J. Parasit. 34:1299-1307) • 2 animals each as control, DRM, IVM and MXD • Poured and then pastured together as one group • Results after 7 days…………… Each control had plasma levels of DRM, IVM and MXD Controls had 2-28% of a ML full dose 5 of 6 non-DRM cows had 2-21% of a full DRM dose 5 of 6 non-IVM cows had 2-17% of a full IVM dose 3 of 6 non-MXD cows had 3-11% of a full MXD dose

Thank you! Bye-Bye /// Bayer 16:9 Template 2010 /// November 2017