1998

Keynote Speaker

Title: The Fundamentals of Profitable Milk Production
Author: Randy Shaver
Summary: Consistency of feeding and management practices is extremely important in dairy production. Pay attention to detail and do the little things right to optimize milk production. Sticking to the proven basics of breeding, feeding, and management is the key to profitable milk production.


I: Priming for Production.

Title: Building A Better Cow – Aggressive Heifer Growing Approaches
Author: Mike Hutjens
Summary: Heifer groups are critical for optimal growth and proper management and may require facility additions and/or modifications. Aggressive heifer growth requires higher nutrient levels than in NRC (9). Heifers must be measured quarterly to determine if growth targets are achieved.

Title: Feeding Management during the Transition Phase
Author: Charles C. Stallings
Summary: For successful transition from the dry period to lactation it is important to maintain nutrient intake pre- and post-calving by using digestible rations that are palatable and nutritionally balanced. Control of potassium and sodium intake is important in preventing metabolic disorders. Use feed additives selectively to stimulate intake and/or digestion, prevent fall of blood calcium, and maintain a strong immune system.

Title: Anion, Vitamin E, and Se Supplementation of Diets for Close-Up Dairy Cows
Authors: David K. Beede and Thomas E. Pilbeam
Summary: Supplementation of anions (Cl- and SO4-2 ) in diets of close-up dairy cows has become more common in recent years to aid in control of hypocalcemia and related peripartum health disorders. These anions are helpful to counteract the deleterious effects of high dietary K on Ca status in the peripartum period. Anions are used to decrease the dietary cation-anion difference (DCAD) which in turn results in mild systemic metabolic acidosis. This is efficacious to increase blood Ca in response to hypocalcemia. Recent research suggests that SO4-2 is a less powerful acidifier than Cl-. This suggests that perhaps we should re-think which is the most appropriate DCAD equation.


II: Feeding and Management Strategies.

Title: Strategies to Maximize Feed Intake and Milk Yield in Early Lactation
Author: Mike Allen
Summary: Energy intake in early lactation is affected by many different environmental, management, animal, and dietary factors. Maximizing energy intake requires appropriate management through all phases of lactation. Diets must be formulated to balance fermentation acid production.

Title: Reproductive Management – A Nutritionist’s Perspective
Author: Jim Spain
Summary: Nutrition management influences reproduction in the dairy cow. Dry cow nutrition must be carefully managed to prevent metabolic diseases that can adversely affect reproductive performance of the dairy herd. Energy balance during early lactation is the second key nutritional factor that affects reproduction. Protein, vitamins and minerals must also be balanced to support optimal reproductive function of the lactating dairy cow.

Title: Ionophores – Mode of Action and Effects on Milk Yield and Milk Composition
Authors: J.J. Kennelly, L. Doepel, and K. Lien
Summary: Ionophores function primarily in the rumen and positively influence energy and protein metabolism. Ionophore supplementation can have a positive influence on post-partum metabolic disorders. In general, ionophore supplementation results in milk fat depression but has little effect on lactose yield or protein content. Increases in milk yield and/or protein content in some studies demonstrate the potential of ionophore supplementation to positively influence milk yield and composition.

Title: Influence of Monensin on Post-Partum Health and Production
Author: Todd Duffield
Summary: Monensin CRC treatment three weeks prior to calving reduced the incidence and duration of subclinical ketosis in early lactation. Precalving monensin treatment improved cow health by reducing the incidence of abomasal displacement and multiple illnesses. Monensin CRC treatment increased milk production in cows having good and fat body condition prior to calving but had no impact in thin cows. Milk components (milk fat percent and milk protein percent) and reproductive performance were unaffected by monensin CRC treatment.


III: Risk Management.

Title: Environmental Risk and Dairy Farming
Authors: Keith Wilson and Jason Krips
Summary: Unincorporated dairy operations are bound by and must follow environmental statutes.Directors and officers of incorporated dairy farming operations owe a fiduciary duty to the corporation and they must take all Areasonable care@ applicable in the circumstances in regards to environmental matters; Directors and officers of dairy farming corporations can be liable under the Alberta Environmental Protection and Enhancement Act and the federal Fisheries Act for the release of substances harmful to the environment or into water frequented by fish

Title: Legal Issues of Risk Management in Agriculture
Author: Russell A. Flint
Summary: Farmers must be aware of legal risks involving the use of agricultural property, and farm business risks. Farmers who fail to properly control their cattle can face liability. A farmer can be held liable for damages caused by substances which are used in accordance with common farming principles that escape from his property. There are several advantages for a dairy producer to operate his farm as a corporation.

Title: Policy Risk: Implications for Dairy Farm Management
Author: Scott R. Jeffrey
Summary: Given recent and potential future changes in the policy environment, policy risk is an important consideration for dairy producers in western Canada. In general, risk may be considered as an additional Acost@ associated with milk production, and should be treated as such in farm management decision making. Dairy producers in western Canada may have to consider alternative risk management strategies in the future, if there are changes in the current supply management system.


IV: Nutrition.

Title: Digestibility of Forage Fiber – Variation, Measurement, and Relationship to Animal Performance
Authors: Mike Allen and Masahito Oba
Summary: Fiber digestibility may be a key factor for maximizing milk production. Increasing fiber digestibility will increase the energy density of diets, will provide more energy to ruminal microbes which may increase microbial protein synthesis, and result in higher DMI. Although higher fiber digestibility can be expected to benefit all ruminants, it may be particularly beneficial to dairy cows in early lactation. These animals usually cannot consume sufficient energy to support requirements and they mobilize body reserves to sustain milk production.

Title: Factors Which Influence Forage Quality and Effectiveness in Dairy Rations
Author: Joe W. West
Summary: Different forage species vary greatly in their digestibility and intake potential. Compared with legumes, grasses often have greater fiber digestibility, but are slower to digest and may limit intake. Increasing maturity reduces digestibility and intake potential for forages, and the effect is greater for grasses than for legumes. Environment affects forage quality, and forages grown under high temperatures are usually of lower digestibility than those grown in cool conditions. Poor quality forage can not be overcome by simply adding more grain (energy) to the diet. Good quality forage provides the basics for sound ration formulation.

Title: Effective Fiber in Barley-Based Diets
Authors: Karen A. Beauchemin and Lyle M. Rode
Summary: Maintaining high ruminal digestion is critical for barley grain to maximize total tract digestion of feed. However, extensive processing also increases the degree of acidity in the rumen. It is important to maintain a balance between over-processing (acidosis, metabolic diseases) and under-processing (reduced digestibility and animal performance). The concentration of neutral detergent fiber from forage sources necessary to maintain 3.5% milk fat in diets based on barley is higher than that for diets based on corn. Extensive processing of barley grain and fine chopping of forages increases the need for forage fiber in the diet to avoid milk fat depression.

Title: Enzymes to Enhance Utilization of Feed in Dairy Cows
Authors: Lyle M. Rode and Karen A. Beauchemin
Summary: Fibrolytic enzymes can be a highly effective means of increasing milk production and diet digestibility in dairy cows consuming a wide range of feedstuffs. Enzymes with similar in vitro activity can differ greatly in their effectiveness when fed to cattle. Method of application is critical to successful use of enzyme technology.  Feed enzymes are more effective when a liquid preparation is sprayed on feed than when included in the diet in a dry formulation. Feed enzymes are more effective when applied to dry forage or concentrates than when applied to wet feeds.

Title: Balancing Minerals and Vitamins for Production, Reproduction and Health
Author: Tim Brown
Summary: Laboratory analyses of feedstuffs for mineral content are essential for balancing minerals in the diet. When selecting sources of supplemental minerals, only those of high bioavailability should be considered. The feeding of minerals in excess of established requirements should be avoided except in certain situations where more of a particular element has proven to provide benefits to the animal.


V: Getting the Most out of Feed Resources.

Title: Calf Management – Birth to Weaning
Author: Tim Brown
Summary: Minimizing calving difficulty provides calves that are more vigorous and easier to raise. Four liters of high quality colostrum within the first 12 hours of life are essential to survival.
Powdered milk replacers differ with regard to ingredient quality. Only those made of high quality ingredients should be fed. Providing clean water and high quality dry starter feed every day will increase growth rates and make weaning less traumatic.

Title: Profitable Forage Management Strategies
Author: Jim Spain

Title: Cost Effectiveness of Feed Additives
Author: Mike Hutjens
Summary: Additives must be cost effective before being included in dairy rations. The role of an additive must be defined and evaluated on individual farms. The additive must be included in the ration at an optimal level.

Title: Buffers – What and When to Use
Author: Joe W. West
Summary: Buffers are effective in maintaining rumen pH and elevating milk fat percentage. In early lactation, buffers can improve dry matter intake and milk yield. Buffers are most effective in diets based on corn silage and which are high in very fermentable carbohydrates. Diets based on alfalfa benefit little from buffering. Low content of forage, small forage particle size, very wet diets, diets high in fermented forages, and diets high in by-products with small particle size favor the use of buffers.

Title: Making Effective Use of Production Management Records
Author: Jim Spain
Summary: Complete and accurate production records should be used to make management decisions. A weak link analysis allows farm managers to prioritize management attention on those most critical weaknesses. Establish Management Action Plans (M.A.P.S.) to implement change. Management lists can be used to isolate cows into management groups that require special attention.


VI: Health and Production.

Title: Fine-Tuning Mastitis Control Programs
Author: Ken E. Leslie
Summary: Implementation of commonly recommended mastitis control practices will dramatically decrease the prevalence of contagious pathogens, but not necessarily reduce clinical mastitis caused by infections with environmental organisms. Udder health management that fulfills the three basic principles of eliminating existing infections, preventing new infections and monitoring udder health status are highly successful. A new udder health management program involving ten steps is now recommended as a comprehensive approach to mastitis control.

Title: Body Energy Management
Author: Dave K. Beede
Summary: Dairy cows must have adequate body energy reserves at the beginning of lactation to maximize milk production and become pregnant. Proper management of body energy begins in the previous lactation, through the dry period. Under-conditioned cows at dry-off must deposit body reserves during the dry period and should be provided the dietary energy to accomplish this via higher energy density diets and (or) by higher dry matter intake. Over-conditioned cows at dry-off and at parturition are more prone to metabolic disorders and suboptimal subsequent lactational performance.

Title: Preventing Abomasal Displacements
Author: Randy Shaver
Summary: Because of intake depression prior to calving and slow intake ascent post-calving, the transition period is the major risk period for abomasal displacements. Feeding and management practices that prevent other calving-related disorders reduce the risk of abomasal displacements. Cows that have excess body condition at calving are at increased risk of ketosis and abomasal displacements. Both excessive and minimal feeding of concentrates pre-calving may increase the risk of abomasal displacements.

Title: Manure Scoring as a Management Tool
Author: Charles C. Stallings
Summary: Manure scoring is not likely to become as popular as body condition scoring as a management tool. There are many factors that can impact on manure visual appearance, not all of which are nutritional. However, there are some things that can be said about observing changes in manure. Cows fed for production are likely to have feces that are more fluid in appearance than feces from cows fed higher fiber rations, although, fecal dry matter may be greater. High levels of ruminally degradable protein supplements can result in feces appearing more fluid, probably a result of increased water consumption in an effort to excrete excess nitrogen via the urine.

1996

Keynote: The Information Superhighway

Title: Getting Your Learners License
Author: Mark Varner
Summary: The Information Superhighway can be thought of as a global network of smaller interconnected computer networks and associated software technologies. Effective use of the Information Superhighway requires utilization of various computer software technologies. The six main technologies are electronic mail (e-mail), telnet, ftp, news groups, Gopher and World Wide Web (Web).


Session I: Positioning for Production

Title: Optimal Body Condition Score at Calving For Production and Health 
Author: Jim Spain
Summary: Changes in body condition score can and should be used to assess the level and change of body fat stores and as an indicator of energy balance. The ideal body condition score will support maximum peak milk production during the negative energy balance of lactation. High producing cows will lose body condition during early lactation, but large losses are associated with lower milk production and lower conception rates. Early lactation cows experience a period on negative energy balance after calving. Severity of negative energy balance can be estimated by monitoring body condition score changes.

Title: Close-Up Dry Period: Feeding Management for a Smooth Transition
Author: Ric Grummer
Summary: Cows will typically experience a 30 to 35% reduction in feed intake during the final two to three weeks prior to calving. Feed and manage cows to maximize feed intake during the transition period. Over conditioned cows are likely to have poor appetites, but do not feed restrict during the dry period. Avoid poor quality forages, unpalatable feeds, and legumes high in potassium during the transition period. Increase concentrate feeding during the transition period to stimulate intake, foster development of rumen papillae, acclimate rumen microorganisms, and reduce fatty acid mobilization from fat stores.

Title: Managing the Feeding System for Optimal Dry Matter Intake
Author: Jim Spain
Summary: Milk production is highly and positively related with dry matter intake. Optimal rumen fermentation must be maintained through proper diet formulation, mixing, and feeding for the cow to reach maximum dry matter intake. High fiber, low energy forages are a primary factor limiting dry matter intake on many dairy farms. Feeding system management to assure adequate access to the diet is also a key controlling point in reaching maximum dry matter intakes.

Ttitle: The Link Between Nutrition, Acidosis, Laminitis and Environment
Author: James E. Nocek
Summary: The link between nutrition, acidosis, and laminitis is the association with nutritional effects on causing metabolic acidosis (decreased rumen pH) and altered hemodynamics of the peripheral microvasculature resulting in hoof deterioration. The severity of laminitis depends on the duration and frequency of metabolic insults (i.e., slug feeding highly fermentable grain once daily).


Session II: Peaking with Persistency

Title: Matching Protein Delivery to Milk Production
Author: William Chalupa and Charles J. Sniffen
Summary: Metabolizable protein and amino acids are provided by ruminal escape feed protein and bacterial protein. Bacterial protein production is regulated by the amount and rumen fermentability of feed carbohydrate. During silage fermentation, some soluble non-cell wall components are metabolized to organic acids. Formation of organic acids has little effect on feed energy values, but can affect protein nutrition because bacteria do not grow on organic acids. Silage based rations may need to contain higher levels of crude protein with greater bypass.

Title: Fuel for Milk: Delivering Carbohydrate to the Rumen and Intestine At the Right Price
Author: James E. Nocek
Summary: The diversity in efficiency of carbohydrate use by microorganisms can significantly influence their growth rate. Grain processing can increase rumen availability of starch by 50% or more. To the level that nonstructural carbohydrate can be added to the diet, increasing the rumen availability of starch is more cost effective in providing essential amino acids (lysine and methionine) through microbial synthesis than supplementation of traditional high protein UIP sources.

Title: Strategies for Successful Fat Supplementation
Author: Ric Grummer
Summary: Many studies indicate that cows do not reduce body weight loss or increase milk yield when fed fat immediately after calving. Oilseeds should be the initial source of supplemental fat.
It is unlikely that too much oil will be fed from oilseeds if feeding guidelines for protein and/or fiber are adhered to. Feed additional fat beyond oilseeds only if body condition scores average less than 3.5 at dry off and body condition replenishment cannot be accomplished through additional grain feeding. Tallow is an acceptable second source of supplemental fat for dairy cows, however, milk fat percentage may be reduced when corn silage or grass is the predominant forage source.


Session III: The Information Super Highway

Title: Surfing the Net
Author: Mark Varner
Summary: Surfing the Net is not only easy, but there is also substantial dairy-related content available. Canadian content leads the world in many ways for this rapidly changing area. The Net should be considered as an important informational resource for all dairy producers and their public/private sector advisors.


Session IV: Keys to Success in Managing 150 Cow Herds: An International Perspective and Implications for Western Canadian Producers United States; Australia; EU; Canada

Title: Positioning Your Dairy Farm Business for a Profitable Future – A US Perspective
Author: Terry R. Smith
Summary: US dairy producers are facing the challenges associated with operating their businesses in a nearly de-regulated dairy economy. Understanding the importance of production, capital and labor efficiency, and economies of size are crucial to positioning a dairy farm business for the future. Some key performance measures and their relationship to dairy profitability help to better understand the opportunities for improving dairy farm profitability from both a short and long run perspective.

Title: Positioning Your Dairy Farm Business for a Profitable Future – An Australasian Perspective
Author: Ian J. Lean
Summary: Australasian dairy production is favored by excellent climates, temperate pastures and, in parts, access to low-cost commodities resulting in a lower cost of production. The challenge facing the smaller farm worldwide is to expand or improve performance in the face of falling prices for milk. Farms that survive will perform better than their peers by managing rather than doing, by improving nutritional management of the herds, and by adapting to change. For Canada to gain a larger portion of the international market Canadian dairy products will need to be unique or of superior quality.

Title: Positioning Your Dairy Farm Business for a Profitable Future – A European Union Perspective
Author: Myles Rath
Summary: The European Union has a very large dairy industry and is a major exporter of subsidized dairy products onto the world market. The existence of producer quotas within the EU has prevented the expansion of milk output since 1984. Failure to control costs in a quota situation is a major reason for low dairy margins. High milk yield per cow does not always lead to high margins in a quota situation and optimizing milk output from forage is one of the keys to profitable dairying. Heavy reliance on grazed grass for milk production seems to limit milk yield per cow due to limits on grass dry matter intake. Efficient grassland management is a very demanding skill and is very difficult to implement.

Title: Positioning Your Dairy Farm Business for a Profitable Future – A Western Canadian Perspective
Author: Timothy J. Richards
Summary: Large producers can reduce costs through increasing their utilization of fixed labor and equipment capacity. A high level of dept causes some large producers to have both higher operating costs and total production costs. The “optimal” herd size in Alberta using the 1989-1991 AMPS Costs of Production Survey data is 140 cows to achieve the lowest operating costs.


Session V: Reproduction

Title: Facts and Fallacies About the Uterus After Calving
Author: Donald J. Klingborg
Summary: Unbelievable. That single word best describes the structure and function of what is one of the most complex organs in the body. The uterus is simply unbelievable. It accepts a substance foreign to itself (the calf), blocks the normal body defenses designed to destroy foreign “invaders”, and nourishes, protects, and sustains the developing calf while the uterus grows from a diameter of about one inch to 24 inches or more.

Title: Neosporosis and Abortion in Dairy Cattle
Author: Mark Anderson, Bradd Barr, Joan Rowe, Karen Sverlow, Andrea Packham and Patricia Conrad
Summary: Fetal infections by the protozoa parasite, Neospora sp., is a newly recognized cause of abortion and congenital infection in cattle. This infection is the most common cause of abortion seen in many dairies throughout the world. Diagnosis of the infection is assisted by examinations of aborted fetuses and serologic testing of cows. At the present time there is no treatment or prevention for the infection and the life cycle of the parasite is not known. Cattle can be chronically infected with Neospora and can pass the infection onto their offspring during pregnancy.


Session VI: Nutrition and Immunity

Title: Potential Therapeutic Uses of Bovine Somatotropin in Cattle
Author: Robert J. Collier and John L. Vicini
Summary: Somatotropin is best known for its role in regulating milk production in cattle. However, this hormone has beneficial effects on other tissues which may provide therapeutic and prophylactic uses for it in the future.

Title: Supplemental Vitamin C May Enhance Immune Function in Dairy Cows
Author: Darren MacLeod, Lech Ozimek and John J. Kennelly
Summary: Ascorbyl-2-polyphosphate is a rumen stable source of ascorbic acid for ruminants. Ascorbic acid supplementation bolsters the immune response of calves. Antioxidant vitamins improve the immune response of dairy cattle.


Session VII: New Technology

Title: Bovine Somatotropin and Monensin: Emerging Technologies
Author: Ian J. Lean, L. Wade and S.D. Beckett
Summary: Both somatotropin (bST) and monensin will increase milk production, bST by acting on metabolism and monensin acting primarily to modify rumen fermentation. Both products can reduce the risk of ketosis. The bST by altering body composition in a prior lactation and monensin by a number of changes in rumen function, which can profoundly reduce ketone concentrations.  Somatotropin generally has a negative effect on fertility of dairy cows, but monensin appears to have had little overall effect in trials to date.

Title: Using DNA Technology to Alter Milk Composition
Author: David R. Glimm, Lech Ozimek, and John J. Kennelly
Summary: Advances in dairy breeding depend on our ability to combine the knowledge of science and technology with the wisdom of nature. Genotyping technology should be immediately transferred to the dairy breeding community. Routine genetic screening should be initiated, first for the major milk protein genes, and then later for other genes of economic importance as they are identified. The recently developed molecular technology of differential display can be applied to identify for the first time genes controlling traits of economic importance.

Title: Enzyme Enhancers: the Key to Unlocking the Energy from Feed
Author: J.A. Shelford, K.-J. Cheng and G.M. Kamande
Summary: An agent has been discovered that will enhance milk production 2.5 to 3.5 kg/cow/day through increased efficiency of feed utilization. Economic return from using such an agent ranges from 4:1 to 7.5:1.

Title: Nutrition Turns On Genes to Enhance Efficiency and Productivity
Author: Erasmus K. Okine, Feng-Qi Zhao and John J. Kennelly
Summary: As feed nutrients are transformed and modified by microorganisms present in the rumen, the supply of nutrients to the mammary gland and other tissues may differ markedly from that present in the diet. Nutrients reaching the gut, liver, mammary gland, and other tissues turn-on genes that in turn produce proteins that control the nutrients available for lactation, reproduction, and body reserves. Our understanding of how nutrients influence gene expression is limited. As we gain a better understanding of the complex relationship between nutrition and gene expression we will be able to more accurately and efficiently deliver nutrients to achieve our target level of milk production.


Session VIII: Nutrition and Environment

Title: Rumen-Protected Amino Acids Improve Milk Production and Milk Protein Yield
Author: Lyle M. Rode and Limin Kung Jr
Summary: Rumen-protected amino acids (RPAA) can be an effective substitute for dietary protein. RPAA can increase milk protein yield . RPAA technology is suitable as part of an environmentally responsible production system.

Title: Impact of Nutrition on Manure Management
Author: William Chalupa and James D. Ferguson
Summary: 20 to 35% of feed nitrogen is captured as milk protein. 65 to 80% of feed nitrogen is excreted in manure. Ration balancing can reduce nitrogen excretion. Ration formulation strategies mainly affect urine nitrogen.


Session IX: Planning for the Future An Economic Perspective

Title: Establishing Indices of Genetic Merit Using Hedonic Pricing: An Application to Dairy bulls in Alberta
Author: Timothy J. Richards and Scott R. Jeffrey
Summary: Market prices for semen can be used to determine the economic value of each trait reported in bull proofs. An increase of one point in a bull’s milk proof increases the marginal value of a bull by $0.70 per dose, whereas an increase in the protein proof has a marginal value of $7.00. Allowing for the positive marginal values to “Final Class” and “Capacity”, improvements in “Feet and Legs” and “Mammary System” have negative values.

Title: Factors Influencing Costs of Milk Production in Alberta
Author: Scott R. Jeffrey and Timothy J. Richards
Summary: Relative economic efficiency will have a significant influence on any reallocation of dairy production resulting from changes in the policy environment. Alberta producers are, on average, relatively efficient in their use of productive inputs (i.e., technical efficiency). Continuing to strive to get the most milk from productive inputs (i.e., being technically efficient) will help to keep Alberta producers competitive with dairy producers in other regions into the future.


Session XI: Mastitis Prevention and Treatment

Title: Quality Milk Production: Milking Practices and Procedures
Author: Andrew P. Johnson
Summary: Milking practices are the key to quality milk production. Quality milk production will be the key ingredient to the future dairy industry. Milking practices must be consistent by all people milking cows. Keep it simple and always milk a clean, dry, and well stimulated teat. Keeping cows clean, dry, and comfortable are essential ways to produce quality milk.

Title: Clinical Mastitis – To Treat or Not To Treat
Author: Stephen C. Nickerson
Summary: Strep. agalactiae is easily cured by approved antibiotic infusion products. Therapy of Staph. aureus mastitis greatly improves with extended or combination therapy. Extra-label treatment requires a valid veterinary/patient/client relationship. Oxytocin is effective in alleviating clinical symptoms of coliform mastitis. Antibiotics are more effective against Gram-positive than Gram-negative organisms.


Session XII: Replacement Heifers Feeding, Management, and Mastitis Prevention

Title: Replacement Heifers: the Key to Future Profits
Author: Andrew P. Johnson
Summary: Heifers are your future dairy herd and to reach their potential they must be properly managed. The sooner the heifers reach the milking herd, the sooner they can make a profit on your dairy. Nutrition and environment are the two areas that impact heifer performance the most. Optimizing heifer growth will help your farm compete today and in the future with all other dairies. Heifer management is an essential part of any farm.

Title: Mastitis Control in Replacement Heifers
Author: Stephen C. Nickerson
Summary: Mastitis is prevalent in breeding age and pregnant dairy heifers. Most infections are caused by Staph. aureus and other staphylococci. Antibiotic infusions during pregnancy or two months prepartum are >90% effective. Successfully treated heifers produce 10% more milk in early lactation. Fly control reduces prevalence of heifer mastitis.