Title: Energy balance changes in cows and matching calving seasons with forage availability
1Energy balance changes in cows and matching
calving seasons with forage availability
21. Tedeschi, L. O., D. G. Fox, M. J. Baker.2004
Unveiling the production efficiency of the beef
cow A systematic approach using nutrition models
modification of paper presented at the NY beef
cattle winter management meeting. Jan.2004
- 2.Reynoso-Campos, O., D. G. Fox, R. W. Blake,M.
C. Barry,L. O. Tedeschi. C. F. Nicholson, H. M.
Kaiser, P. A. Oltenacu.2004.
Predicting nutritional requirements and lactation
performance of dual-purpose cows using a dynamic
model. Agricultural Systems. 8067-83
3PAPER 1Tedeschi., L. O., D. G. Fox, M. J.
Baker.2004 Unveiling the production
efficiency of the beef cow A systematic
approach using nutrition models
modification of paper
- Increase beef production
- -Enhance reproduction indexes
- -Enhance nutrition concepts
- -Enhance genetic selection
- - Enhance ranch management
4This paper introduces a model (CVDS) which
Tedeschi is developing.
- The objectives of the model
- Computing the energy requirements of individual
beef cows each day of the year and simulating the
growth of the nursing calf given the information
available - Computing energy balances for the herd each day
of the year to evaluate the balance between herd
numbers and requirements with the forage
available - Identifying differences in efficiency among
individual beef cows in a herd
5The brief description of the model
- This model is based on those developed at Cornell
as described by - Reynoso-Campos et al.(2004)
-
- Fox et al. (1988)
-
6An evaluation of the model, as the peak milk
yield increases, the weaning weight increases.
7An evaluation of the model, energy efficiency of
the cows
8Tedeschi implies
- Forage availability, milk yield, calf growth, and
calving interval -
- -The milk level should be based on forage
available. -
9A practical application of the model
10A practical application of the model
11Hints from the Tedeschis paper for our Yucatan
case
- 1. The milk level should be based on forage
available. - 2. Matching breeding and calving seasons with
availability of forage.
12Reynoso-Campos et al
Reynoso-Campos, O., D. G. Fox, R. W. Blake,M. C.
Barry,L. O. Tedeschi. C. F. Nicholson, H. M.
Kaiser, P. A. Oltenacu.2004. Predicting
nutritional requirements and lactation
performance of dual-purpose cows using a dynamic
model. Agricultural Systems. 8067-83
13- Animal nutrition
- Cornell Net Carbohydrate and Protein
System(CNCPS) - -Milk production
- -ME balance
- -MP balance
- -BW change
- -Changes in Body reserve
- through the reproductive cycle.
-
14Look at table 1. Page 70-71.
- Table 1 is nicely summarized nutritional
constraints and strategies for intensifying
dual-purpose cattle systems in the tropics. - This table is related to our Yucatan beef project
very much.
15Objectives of this study 1
- 1.
- Describe a dynamic application of the CNCPS
model that was developed to account for the
cyclical changes in energy and protein balances
that occur during the reproductive cycle of
dual-purpose cows in the tropics.
16Objectives of this study 2
- 2.
- Demonstrate the use of this dynamic
application of the CNCPS model in evaluating
dual-purpose cow performance over the
reproductive cycle in specific production
situations.
17Inputs for the simulation
- Crossbred of Holstein x Brahman
- 2nd lactation
- Age --- 65 mo
- CI --- 420days
- Dry periods150 days
- Weight --- 470 kg
- Calf BW--- 31.5 kg
- Temperature
- -Previous 26C
- -Current 26C
- Milk
- -Production 11.5
- kg/day
- -Fat 4.1
- -Protein 3.9
- Rolling herd average
- --- 2500 kg/270 day lactation with the
CI of 420 days
18Feed information
- Lactating cows
- -Graze forage Star grass (Cynodon
- plectostachyus)
- - 2 kg of commercial supplement
(Both energy and protein concentrates) - Non-lactating
- -Only grazed forage
19Chemical components of Star grassJuarez et al.,
1999
- Lactating (fertilized)
- NDF --- 71.6
- CP --- 10
- Lignin 7.3
- NDF digestion rate
- --- 7.0 /h
- Dry (unfertilized)
- NDF --- 78.3
- CP --- 6.6
- Lignin 7.6
- NDF digestion rate
- --- 5.0 /h
20Source , Reynoso-Campos et al.,2004
21Source, Reynoso-Campos et al.,2004
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23Source, Reynoso-Campos et al.,2003
24Comparison of ME allowable milk with and without
ME contribution from mobilized body tissue
25Conclusion by Reynoso et al
- The CNCPS analyzes and integrates the
nutritional and productive performance of cows on
a dynamic basis throughout a calving interval. - Changes in the predicted nutritional status of
animals reflect dynamic, cyclic processes of
tissue mobilization and repletion associated with
variation in production requirements and nutrient
availability during the CI
26Hints from the Reynosos paper for our Yucatan
case
- The CNCPS is a useful tool to monitor energy
balance through the calving interval. - The CNCPS can show the tissue mobilization and
repletion in the prediction of nutrient
requirement
27My conclusion
- Energy balance, protein balance, and body
condition score are different from physiological
stages (early or late lactation, and early or
late pregnancy), and feed quality and quantity.
Not accounting for the fluxes of body tissue
leads to unrealistic predictions of dietary
requirements. - It is important to think about forage
availability, and energy requirements for each
physiological stage -
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