Dairy Resources - Growing Heifer Replacements

December 2020

ABSTRACT:

Pair housing of dairy heifer calves during the preweaning period helps meet the natural social needs of the calf and has been shown to improve growth and starter intake during the preweaning period as compared with individual housing. However, there is little evidence to suggest that pair-housed calves maintain their social and growth advantages past the weaning phase. The objective of this study was to investigate the effect of pair housing on measures of calf performance, health, and behavior up to 16 wk of age. Healthy Holstein and crossbred heifer calves were enrolled in the study after colostrum feeding, with the first calf randomly assigned to 1 of 2 housing treatments: pair (PR; 2 hutches with common outdoor space) or individual (INDV; 1 hutch plus outdoor space). All calves were bucket fed 4 L of milk replacer twice daily and weaned at 50 d of age. Weaned calves (6/group) remained with their treatment group until exit from the study at 16 wk. A venous blood sample was collected from each calf between 24 h and 7 d of age to test for serum total protein (g/dL). Body weights (kg) were obtained at birth, weaning, and 16 wk. Each enrolled calf was scored for health each week and calf health treatments were also collected. A hair sample was collected from the left shoulder at birth and 16 wk to assess hair cortisol (pg/mL). At enrollment, each calf was fitted with a triaxial accelerometer on the left hind leg for continuous recording of standing and lying time (min/24 h) for 16 wk. Latency to find feed, water, and lie down (min) at entrance to the weaned pen were recorded by continuous video observation. Open field testing with a novel object was performed at 5, 10, and 16 wk. Behaviors analyzed by video observation included latency to approach the object (s), vocalizations (n), and time spent immobile, walking, or running (s/10 min). Linear mixed models were used to determine the effect of treatment (INDV or PR) on calf growth, activity, and behavioral outcomes, which accounted for time, breed, the interaction of time and treatment, the random pen, and variability in testing day and repeated measurements within calf when appropriate. Twenty-four Holstein and crossbred calves (PR: n = 12, 6 pairs; INDV: n = 12) were enrolled from November 2 to December 23, 2018. The PR calves were 7.1 kg heavier at weaning and gained 0.15 kg/d more during the preweaning period as compared with INDV calves. In the 24 h after movement to the post weaning pen, PR calves lay down for longer periods of time (14.3 vs. 11.0 ± 0.4 h/d), and PR calves urinated more during novel object testing at 5 wk of age. Our study demonstrated benefits, such as better growth and increased lying time, of pair housing calves during the preweaning period.

W.A. Knauer, S.M. Godden, A.K. Rendahl, M.I. Endres, B.A. Crooker
DOI: https://doi.org/10.3168/jds.2020-18928

December 2020

When a heifer comes into heat, it’s important to take a peek at her birth date before making the decision whether or not to stick semen in her. Why? Because the age she calves could affect the amount of milk she produces throughout her first lactation, according to a 15-year study conducted in Belgium and the Netherlands.

October 2020

Creating lifelong immunity in baby calves has never been more important. A proactive approach to health, nutrition, and management is a must from day one. Having a proper program in place not only improves the animal's health, it can also improve resilience to stress and disease. By implementing adequate colostrum protocols, feeding a consistent diet of whole milk or milk replacer, and incorporating immune support products into the liquid ration, your calves will have the greatest chance of success.

October 2020

“I need to switch calf starters; this one is causing acidosis.”

Have any of these thoughts crossed your mind? If so, you’re not alone. But, you might be missing the real question – do your calves actually have acidosis?

September 2020

Properly storing, handling and mixing milk replacer not only helps the product retain its quality, it also ensures calves are consistently fed. Although it seems that mixing powder and water is simple, many issues can occur that impact both powder quality and animal performance.

Proper milk replacer storage

Proper milk replacer storage is imperative to help the product retain its quality. Milk replacer quality can be negatively impacted by changing humidity and temperatures, which can result in spoilage, fat oxidation and issues with mixing and reconstituting powder. As a result, the best storage method for milk replacer powder is in a temperature- and humidity-controlled area. If it is not in a temperature- and humidity-controlled area or room, stored milk replacer can absorb moisture, leading to condensation and clumping. Fat oxidation, rancidity and spoilage that follows can impact odor and taste and even the nutritional value of the powder.

Proper storage once open is also crucial. The milk replacer bag should be in an airtight container to help minimize exposure to any humidity, as well as pests. Another thing to consider when storing milk replacer includes storing bags on a pallet to aid in preventing moisture absorption and not stacking pallets to prevent compaction. If space is an issue and pallets must be stacked, they should not be more than two pallets high. While not every farm may be able to meet all of these conditions, they should strive to meet as many as they can.

Proper milk replacer handling and mixing

Even if proper storage of milk replacer occurs, improper handling and/or mixing can still lead to additional issues with both powder and calves. Most milk replacers come with simple, easy to follow instructions. First, it is important to ensure you are measuring milk replacer powder correctly. It is advised to weigh the powder. If it is not possible to weigh the powder at each feeding, then frequently weigh the powder in the measuring scoop to ensure the weight is accurate – even if it is the scoop is provided by the manufacturer, as the density of powder can change. The amount of powder and water to mix will depend on many things. For instance, the number of calves and what percent solids you plan to feed (see Table 1). It is important to note that as percent solids increase, the osmolality of the milk replacer also increases, which can potentially lead to abomasal bloat and other digestive disturbances, therefore considerations should be made when increasing solids percentage of milk replacer.

Milk replacer quality can also be affected by improper mixing. If mixing water is above 145°F, milk replacer powder will be negatively impacted. High water temperatures can denature proteins, leading to poor digestibility. High temperatures can undo the emulsification process that occurs during manufacturing, leading to clumping of fat molecules, which can cause fat deposits on mixing and feeding equipment. This can also lead to some calves consuming more fat than others.

Proper milk replacer feeding

It is important that milk replacer is fed around 102° to 107°F, which is close to the body temperature of a healthy calf. If milk replacer is colder than body temperature, the calf will warm the milk after it is consumed, leading to a loss of energy. Warm milk replacer also stimulates the esophageal groove to close to prevent liquid from entering the rumen, where it can lead to undesirable bacterial growth.

Keep in mind that during winter months, cold feeding equipment (bottles or pails) can reduce the temperature of milk replacer. It is also beneficial to bring the next bag(s) of milk replacer into a warm room prior to use to prevent it from cooling down the mixing water. Mixing water temperature can also be increased in the winter to up to 130°F, if powder is cold, but dilute it with colder water to bring it back down to feeding temperature. Use of a thermometer is strongly recommended and will ensure calves receive milk replacer at the proper temperature. While the temperature may start at 102°F, it can easily cool 10º or more by the time it’s fed to the last calf.

Many of these suggestions should also be considered when using an automated calf feeder, including checking that the machine is properly calibrated and that milk replacer powder is at room temperature prior to adding it to the machine to ensure calves are fed liquid that meets target solids percent and temperature.

Take home points:

1. Storing milk replacer in an airtight container, as well as in a temperature- and humidity-controlled environment, will ensure it retains its quality.
2. It is important to follow manufacturer’s instructions to properly mix milk replacer. It is best to frequently weigh powder to calibrate measuring cups, as the density can vary.
3. Avoid using water over 145ºF to prevent undoing emulsification and denaturing proteins.
4. Make sure temperature of milk replacer fed is between 102º and 107ºF for every calf, to prevent issues.

Kayla Aragona
for Progressive Dairy

September 2020

Pair raising calves is increasing in popularity in the North American dairy industry, where some welfare and productivity benefits have been consistently shown in recent studies.

May 2020

By improving the air ventilation in the dairy calf barn, Gabe Middleton’s experience and industry research show dairy calves are more likely to thrive and have fewer incidences of bovine respiratory disease. He addressed the topic during the 2020 American Association of Bovine Practitioners Recent Graduate Conference. ( Gabe Middleton )

A conversation Gabe Middleton had with a mentor a few years ago struck a chord with the large animal veterinarian.

“He said when you leave a conference, you should have something you can take back to your clinic that helps clients and makes money,” recalls Middleton, a partner in the Orrville Veterinary Clinic, Orrville, Ohio.

For Middleton, one of those “somethings” became the use of positive pressure tube ventilation (PPTV) systems in dairy calf and heifer facilities. The systems reduce air bacterial counts and noxious agents in barns by driving fresh, outside air into the microenvironment of the calf.

July 2019

Heins Family Farms in Higginsville, MO ( Wyatt Bechtel )

The scorching summer sun has thermometers boiling and the humidity in the air is downright stifling. Want to hear the scary part? We’re only halfway done with the season!

Heat stress is a major concern on dairy operations during the dog days of summer, but the majority of farmers tend focus on the lactating animals first. While it is critical to keep the milking herd cool, we can’t forget to help calves chill off, too.

Here are five tips to keep calves refreshed during this sizzling heat!

June 2019

Weaning is a highly stressful time for calves, and placing them in a comfortable environment is key to helping them make the transition to healthy, growing, fully functional ruminants. ( Farm Journal )

All dairy calf housing should be clean, dry, comfortable and well-ventilated. But newly weaned calves have even more specific housing needs, according to Penn State Extension agricultural engineer Dan McFarland. 

August, 2018

Noelia Silva-del-Rio, Dairy Production Medicine Specialist at the University of California’s Veterinary Medicine Teaching and Research Center near Tulare, Calif., conducted a study to pursue this question. Hint: the results were encouraging. ( Wyatt Bechtel )