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• Mycotoxins can reduce dairy cattle immunity and reproduction. Monitoring the level and type of mycotoxins is important.
• Reducing dietary phosphorous levels can maintain milk yield and fertility while reducing manure levels and soil build up.
• Several economical by-product feeds are available to reduce feed costs.

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Heifer age at conception tended to be linearly associated with sex ratio of single calves: from 45(male):55(female) at 14 months to 60:40 at 19 months. A 14% reduction in the value of calves from heifers could occur over this range at a heifer:bull calf price ratio of 3:1.

Sex ratio of single calves born to multiparous cows tended to increase linearly from 53:47 to 57:43 as number of inseminations increased from 1 to 5. This result suggested that cows in better body condition produced a higher proportion of bull calves, and could represent a 4% reduction in the value of their calves.

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• Dry period duration may be optimized between 42 and 60 days, but fewer than 30 days results in significant production loss in the next lactation
• Greater milking frequency of cows that receive a short dry period may lessen the reductions in yield in the next lactation
• Short day photoperiod is recommended for dry cows for the entire dry period, and 21 d of short days is not sufficient to consistently improve yields
• Emerging data on dry cow time budgets suggests that stall comfort and availability is as important to dry cows as to those in lactation

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• The vast majority of producers consider themselves as environmentalist and are incorporating “best management practices” on their dairy farm.
• A clean, well-kept farmstead will result in an improved perception of animal agriculture by the general public.
• Conduct a self-evaluation or have an unbiased third party conduct an environmental assessment of your facility to determine possible concerns.
• Keep a good line of communication among yourself, neighbors, and regulatory staff to prevent problems or be able to resolve problems amiably.

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• Know your cost of producing milk
• Record high milk prices in 2004 resulted in returns exceeding total costs
• Profit margins should remain positive for producers in 2005

DAIRY AWARDS AND SCHOLARSHIPS

The Department of Animal Sciences, University of Illinois, Urbana-Champaign, provides for the management of scholarships and dairy production awards to outstanding incoming freshmen or transfer students. Each award requires acceptance and enrollment in the Department of Animal Sciences, University of Illinois at Urbana-Champaign (UIUC).

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• Milk production per unit of crude protein (CP) in the dietary dry matter increases at a decreasing rate as the CP percentage of the diet increases.
• Compared with soybean meal (SBM), milk production responses to rumen undegradable protein (RUP) supplements ranged from -2.5% to +2.75%. Treated soy products provided the largest increase in milk production (2.75%) and that in part, may be explained by increased dry matter intake (DMI).
• Compared with SBM, fish meal provided the largest improvement in milk CP yield (2.5%) but depressed milk fat yield (-3.5%).
• Efficiency of nitrogen utilization and the cost to benefit ratio for these CP supplements should determine the source and amount of CP to feed to dairy cows.

DAIRY JUDGING TEAM RESULTS

The 2005 University of Illinois dairy judging team was comprised of three seniors and two juniors and was coached by Gene McCoy and David Miller. Team members Julie Drendel, Rebecca Harms, Bill Jansen, and Kim Stevens competed in the Mid South Dairy collegiate contest in Memphis TN. The team was 5th overall and 3rd in Reasons out of 14 teams. Jansen, Harms, and Stevens competed in the National Collegiate Dairy Judging Contest in Madison WI. The team placed 17th out of 24 teams. Julie Drendel, Ryan Graham, and Kim Stevens competed in the North American Collegiate Dairy Judging Contest in Louisville, KY on November 6th. The team placed 16th with Julie Drendel placing 2nd in Ayrshires.

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• Dry matter intake, milk fat percentage and production, 4% fat-corrected milk production, milk true protein percentage, milk lactose percentage, and milk solids-not-fat percentage increased linearly as dietary cation-anion difference increased from -3 to +47 milliequivalents/100 g of dry matter.
• An elevated blood plasma essential amino acid to nonessential amino acid ratio with increasing dietary cation-anion difference indicated that nitrogen metabolism in the rumen was affected, probably resulting in more microbial protein flowing to the small intestine.
• The dry matter intake, milk production and milk composition, and acid-base status did not differ between 16 and 19% crude protein treatments. Feeding 16% dietary crude protein to cows in early lactation, compared to 19% crude protein, maintained lactation performance while reducing urea nitrogen in milk and urine.

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• Although breed differences were expected and significant statistically, intake of dry matter and performance of fresh cows were not improved when dietary cation-anion difference increased from 22 to 47 meq/100 g of dry matter. This was likely because cows immediately after calving respond more variably to dietary treatments and that makes treatment effects more difficult to detect.
• As in the companion experiment, an elevated blood plasma essential amino acid to nonessential amino acid ratio with increasing dietary cation-anion difference indicated that nitrogen metabolism in the rumen was affected, probably resulting in more microbial protein flowing to the small intestine.

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• L-Carnitine is the naturally-occurring compound required for oxidation of long-chain nonesterified fatty acids (NEFA).
• Previous research in our laboratory has demonstrated that postruminal infusion of L-carnitine reduced liver fat accumulation in feed-restricted lactating cows.
• In transition dairy cows, dietary supplementation of L-carnitine (≥ 6 g per day) decreased liver fat concentration, which may reduce the risk of metabolic disorders and improve cow health.
• Further research is required to develop a cost-effective, rumen-stable source of L-carnitine for use in dairy cow rations.

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• Dairy rations balanced for negative dietary cation-anion difference (DCAD) are effective for reducing the incidence of subclinical and clinical hypocalcemia.
• Based on previous field studies, a sulfur-based anionic salt pellet may maintain blood calcium concentrations without affecting urine pH.
• A commercial sulfur-based anionic salt pellet maintained peripartal plasma Ca content without altering urine pH.
• Use of this commercial product may not require monitoring of urine pH in transition dairy cows.

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• Addition of silage inoculants improved the fermentation profile of corn silage and alfalfa silage
• Inoculated corn silage had greater aerobic stability at feed out compared to untreated silage

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• A commercial drinkable drench product can significantly reduce serum NEFA and BHBA concentrations, and tend to increase serum glucose concentrations within hours after administration immediately following parturition.
• Drenching 900g of a drinkable drench product is as effective as 355ml of propylene glycol, an equivalent amount of glucose precursor.

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• Large variation exists in the effects of rumen undegradable protein (RUP) onpassage of nitrogen (N) fractions and amino acids to the small intestine of dairy cows.
• A portion of this variation is caused by the source of crude protein (CP) in the control diet, proportion and source of RUP in experimental diet, effect of RUP on ruminal outflow of microbial protein, degradability of the RUP source, and the amino acid content of RUP outflow from rumen.

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• Periparturient dairy cows undergo a period of reduced immunological capacity during the transition period. This immune dysfunction is broad in scope and affects numerous functions of various tissues and cell types. As a consequence, cows are highly sensitive to invading pathogens and more susceptible to infectious diseases particularly mastitis.
• The negative energy balance ( NEB) that accompanies a reduction in feed intake around calving time is an important contributor to reduced immune competence by the cow. The metabolic stress of lactation, which contributes to NEB, exacerbates this problem in the transition period. Therefore, nutritional status may be of particular importance around the time of calving.
• In a recently funded project, we propose that mammary gland tissue is a key mediator of the effects of NEB on susceptibility to clinical inflammatory diseases. Data on gene expression in mammary tissue from cows fed to NRC (2001) requirements or underfed and receiving a mammary challenge of Streptococcus uberis, will provide new information on the role of plane of nutrition in the susceptibility of cows to develop mastitis.

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• Fresh cows in large herds that were fed propylene glycol as a feed additive were at a slightly increased risk of developing a displaced abomasum.
• The prevalence and incidence of displaced abomasums in the three Illinois counties was four percent.
• Seventy-nine percent of the cows that developed a displaced abomasum recovered after treatment, thirteen percent were culled, and nine percent died due to complications.
• The average economic loss (milk losses/veterinary expenses) for cows that develop a displaced abomasum can range from $305 to $690 per incident.
• Thirty percent of the dairy producers in this survey had a DA percentage of over five percent.

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• Feeding quality forages can optimize milk production, improve cow health, reduce purchased feed costs, and increase dairy profitability.
• Harvesting alfalfa based on plant maturity will have the greatest effect on forage quality.
• Understanding forage nutrient analysis is important in balancing rations and selecting forage varieties.

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• Milk cultures are the only mechanism dairy producers have to determine the mastitis pathogen profile of the organisms infecting their cows.
• Several approaches to milk cultures are available including bulk tank monitoring, herd surveys, and strategic sampling of specific cows (dry off, fresh cows, and clinical cases).
• Milk cultures can be performed on-farm to help guide more efficacious treatment decisions.

ILDG was organized in May, 2003, and includes the Illinois Beef Association, Illinois Pork Producers Association, Illinois Corn Marketing Board, Illinois Soybean Checkoff Board, Illinois Milk Producers Association, and Illinois Farm Bureau. It’s goal is to attract and enhance a profitable livestock industry for Illinois. These six agriculture groups are committed to increasing the total number of livestock in Illinois on both large farms and smaller operations, to improving the efficiency of livestock operations, to developing new markets at home and abroad, and to facilitating new production systems.  This will be accomplished with the Illinois Livestock Development Plan which consists of a three-year, producer-driven effort to enhance the livestock industry's profitability and increase the total number of livestock and poultry in the state.

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• Standard operating procedures insure uniformly applied decisions on dairy farms.
• Staff must understand why the protocol is important and its impact on their time and farm success.
• Health protocols should be comprehensive, timely, have a desirable benefit to cost ratio, and based on lab culture.

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• Microarray technology is a new molecular tool that allows simultaneous analysis of thousands of genes in a tissue sample.   We are the first research group in the world to apply this advanced technology to problems of dairy cattle physiology and nutrition.
• Restricted energy intake before calving resulted in earlier (i.e. day -14 relative to parturition) up-regulation of genes with key functions in liver fatty acid oxidation, gluconeogenesis, and cholesterol synthesis, among others.
• Ad libitum feeding up-regulated a number of genes associated with liver triglyceride synthesis and pro-inflammatory cytokines; these responses corresponded closely with increased liver triglyceride concentrations early postpartum.
• Moderate overfeeding of energy in the dry period results in transcriptional changes predisposing cows to fatty liver, which may compromise overall liver health during the periparturient period.
• Restricted energy intake may confer an advantage to the cow by triggering adaptations of molecular mechanisms in the liver well ahead of parturition.

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• Pounds of milk protein and milk fat dictate the economic impact of milk components and milk yield.
• Milk fat test is impacted by numerous factors.
• Increasing milk protein percent is more difficult to change.
• Dairy managers must provide the nutrients needed by the mammary gland in the blood for milk yield and components.

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• Illinois is currently enrolling animal production units for premise ID http://www.agr.state.il.us/premiseid/
• Premise ID is the foundation for individual animal identification, which will begin by 2009
• Individual identification will initially be by visual methods, but that will transition to electronic methods

The Department of Animal Sciences sends its greetings to our friends and stakeholders in the dairy industry. On the following pages you will find a summary of dairy research conducted by the faculty, staff, and students in both Animal Sciences and Veterinary Medicine. The work reported here represents some of the very best research with dairy cattle conducted in the world. It fulfills the most rigid standards for scientific merit and it addresses topics of foremost relevance to the dairy industry. We are proud of this work and hope you find it pertinent to your interests.