Monday, August 20, 2018

Colostrum Yields and Photoperiod

Nearly all dairies have frustrating times when their supply of good quality colostrum runs short. In an investigation involving one 2,500 cow Jersey dairy they observed a connection between photoperiod and volume of colostrum harvested.

The average colostrum yield was 14.5 pounds (6.6kg) in June and 5.5 pounds (2.5kg) in December. The subsequent May colostrum yield was back up to 10.6 pounds (4.8kg). Up and down and back up again pattern.

The seasonal (photoperiod variation) differences were greater for second and later lactation cows than first lactation cows (correlations ware respectively 0.84 and 0.53).

Genetics played a strong role in overall colostrum volume produced - but, aside from that there remained a strong seasonal effect. 

Thus, the authors summarized, "These data indicate that photoperiod, in some cow families, may be involved with seasonal low colostrum production in Jersey cows." p 154

Reference: Gavin, K. and Others, " Factors associated with low colostrum yield in Jersey cows." JDS Vol 101,  Suppl 2, ADSA 2018 abstracts # 99 p154.

Friday, August 17, 2018

Calf to Calving video

AHDB in UK has released an interesting video which "features our six top tips for heifer rearing."

https://www.youtube.com/watch?v=XB7yjObyNEw is the link to the video.

Featured are comments from dairy farmers that participated in AHDB's "Calf to Calving" program.

If you are not already familiar with their web resources on calf management try this link:

https://dairy.ahdb.org.uk/technical-information/calf-to-calving/#.W3Wb6SRKi1t 

Scroll to the bottom of the page to see the resource folders.

Enjoy.

[AHDB = Agriculture & Horticulture Development Board]

Thursday, August 16, 2018

Think Seriously about Heat Stress on Dry Cows

Many dairies have adopted heat abatement programs for lactating dairy cows. But, what about the dry cows? Do you have the attitude, "So, who can afford heat abatement equipment for dry cows? How am I going to get paid back for making them more comfortable?"

Using data from Florida (the southern most state in eastern US) a research team looked at the consequences of heat stress on not only the cows but subsequent milk production of their daughters and grand-daughters.

They found significantly lower production among the daughters and even the grand-daughters of the heat stressed dry cows compared to cows that had experienced heat abatement during their dry period. 

Grand-daughters from heat-stress grand-dams produced in their first lactation 8 pounds/day (3.7kg) less milk when compared to their herd mates whose grand-dams had experienced heat abatement environments. when all other factors were accounted for. [63 pounds/day (28.5kg) compared to 71 pounds per day day (32.2kg)] 

During their second lactation these same cows from heat-stressed grand dams produced 14 pounds/day (14.3kg) less milk when compared to their herd mates whose grand-dams had experienced heat abatement environments when all other factors were accounted for. [75 pounds/day (34kg) compared to 89 pounds/day (40.5kg)].

Reference: Laporta, J. and Others, "Dry period heat stress reduces dam, daughter, and grand-daughter productivity." 2018 ADSA abstracts JDS Vol 101, Suppl 2 p151

Monday, August 13, 2018

Hot Weather and Hutch Management

During hot summer weather we are correctly concerned about calf comfort in our hutch housing. In recent research four different hutch treatments were compared. 

At one extreme design, the hutch had only one fixed size vent in the rear and was flat on the stone base. At the other extreme, the hutch had the fixed size rear vent and was elevated 6" (15cm) in the rear. Intermediate designs were flat on the stone base with greater vent areas.

The outcomes were:

1.  No difference in weight gain across 4 hutch types.

2. The temperature-humidity index inside the hutches did vary under hot conditions (for example, 92F-20% RH, 95F-10%RH) when comparing the two extreme designs. This suggests that calves may have been more comfortable in hutches that were raised 6" in rear compared to those flat on the stone base. 

But, management can influence the effectiveness of raising the rear of hutches in decreasing the temperature-humidity index. The below left picture shows the desired open area to allow air movement. The picture at the right shows how careless handling of straw bedding has blocked the opening at the rear of the hutch. In the center below, wood shavings have been thrown into the back of the hutch, again blocking most of the air vent.








(Reuscher, K.J. and Others, "Effect of calf hutch type on calf performance and calf hutch temperature-humidity index" Journal of Dairy Science Supplement 2, 101:18 July 2018)

Friday, August 10, 2018

Stretching Your Supply of High Quality Colostrum

By using Brix values for colostrum we can consider a strategy for stretching our supply of high quality colostrum.

Okay, just how to do this?

First, test colostrum to estimate concentration of antibodies. On a Brix refractometer if we get a reading between 22 and 23  we estimate that roughly 4 quarts (3.8L) of colostrum will deliver about 200 g of IgG's. 

Second, recent research suggests that overfeeding IgG's at one feeding does not improve circulating antibodies in the calf's blood. That is, once the threshold of IgG delivery is reached feeding more colostrum will not improve the calf's immunity status. 

Now, let's say we have colostrum that tests 25 or 27 Brix. Rather than feeding the standard 4 quarts these research findings suggest we can cut back that volume and have some leftover colostrum for the next calf. All we need is a tidy chart that tells us based on the Brix reading how much less colostrum needs to be fed.

Too bad. I don't know of any such chart. However, the principle is still valid. If we our high quality colostrum supply is really tight one workable solution may be to cut back our 4 quart volume to only 3 quarts for average size large breed newborn calves when we have extra-high testing colostrum.

Summary
In order to stretch our supply of high quality colostrum for first feeding newborn calves, when we have colostrum testing above 23 Brix consider reducing the volume fed from the "normal" 4 quarts to a lower volume to reach an acceptable threshold of IgG delivery.

Reference: Reiff, O.M. and Others, " Does considering immunoglobulin G concentration alone constitute a physiology-based colostrum management program?" Journal of Dairy Science 101:Supplement 2 Abstract M35, p19.

Tuesday, August 7, 2018

Getting Calves Off to a Good Start
with Acidified Group Feeding

One of my clients is feeding acidified milk. This is group housing. They want to get their youngest calves to eat well in the group housing.

Nursery Pen - Acidified milk feeding
As we can see in the picture of the special nursery pen at the right there are three milk feeding  nipples. Calves come to the pen from the calving area after they have received their colostrum feedings. 

About four to five times a day a calf care person comes to the pen to assist calves in finding the nipples. They stay in this pen only until they have learned to nurse. Turnover is fairly rapid.

Today there were four calves in the pen. The bedding is changed daily. The nursing station is cleaned and disinfected daily as well.

The destination pens, an example is shown at left, are filled from the nursery pen. In this group setting there is significant competition for nursing space. These calf care folks want the calves coming into the pen to be assertive and confident about finding the nipples and nursing. 

Wednesday, August 1, 2018

Quality Calf Care Depends on Quality 
Communication Among Calf Care Workers

The August issue of the calf management newsletter is now posted on line HERE or paste this URL in your browser  http://atticacows.com/library/newsletters/CEAug2018.pdf 

Key points are:
  • Providing consistent care for young calves is a significant condition for successful calf management.
  • The behaviors and health conditions of young calves are highly variable and can change very rapidly.
  • Reliable person-to-person communication is essential for quality calf care.
  • Pictures of on-farm examples.