UPSC MainsANI-HUSB-VETER-SCIENCE-PAPER-I201515 Marks
Q17.

Dairy Cow Ration Computation

Compute a ration for a dairy cow weighing 400 kg and yielding 10 kg of milk with 4% fat from wheat straw (0% DCP and 40% TDN), green berseem (2% DCP and 12% TDN) limited to 15 kg and concentrate mixture (12% DCP and 70% TDN). The maintenance requirement is 250 g DCP and 3 kg TDN, whereas the requirement for 1 kg milk production is 45 g DCP and 300 g TDN.

How to Approach

This question requires a practical understanding of animal nutrition and ration formulation. The approach should involve first calculating the total DCP and TDN requirements based on maintenance and milk production. Then, formulate a ration using the given feedstuffs, ensuring the requirements are met while respecting the limitations on green berseem. A tabular representation will be used to clearly show the ration composition and nutrient contribution. It's crucial to demonstrate the calculations step-by-step.

Model Answer

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Introduction

Dairy farming is a critical component of India’s agricultural economy, contributing significantly to rural livelihoods and milk production. Optimizing feed efficiency is paramount for enhancing milk yield and profitability for dairy farmers. Ration formulation, a key aspect of dairy animal management, involves balancing the nutrient requirements of the animal with available feed resources. This question assesses the ability to apply principles of animal nutrition to formulate a balanced ration for a dairy cow, considering various feedstuffs and their nutrient composition. The National Dairy Development Board (NDDB) plays a crucial role in promoting efficient dairy farming practices across the country.

Calculating Nutrient Requirements

First, we need to determine the total Daily Digestible Nutrient (TDN) and Digestible Crude Protein (DCP) requirements for the cow.

  • Maintenance Requirement:
    • DCP: 250g
    • TDN: 3 kg = 3000g
  • Milk Production Requirement (10 kg milk):
    • DCP: 10 kg * 45g = 450g
    • TDN: 10 kg * 300g = 3000g
  • Total Daily Requirement:
    • DCP: 250g + 450g = 700g
    • TDN: 3000g + 3000g = 6000g

    Ration Formulation

    We have the following feedstuffs available:

    • Wheat Straw: 0% DCP, 40% TDN
    • Green Berseem: 2% DCP, 12% TDN (limited to 15 kg)
    • Concentrate Mixture: 12% DCP, 70% TDN

    Let's denote the quantity of each feedstuff as follows:

    • WS = Wheat Straw (kg)
    • GB = Green Berseem (kg)
    • CM = Concentrate Mixture (kg)

    We know GB ≤ 15 kg. We need to formulate a ration that meets the DCP and TDN requirements.

    Considering Green Berseem (GB) as 15 kg (maximum allowed):

    • DCP from GB: 15 kg * 0.02 = 0.3 kg = 300g
    • TDN from GB: 15 kg * 0.12 = 1.8 kg = 1800g

    Remaining Requirements:

    • DCP: 700g - 300g = 400g
    • TDN: 6000g - 1800g = 4200g

    Now we need to meet these remaining requirements with Wheat Straw and Concentrate Mixture.

    Let’s assume the ration composition:

    Feedstuff Quantity (kg) DCP (g) TDN (g)
    Green Berseem 15 300 1800
    Wheat Straw 5 0 2000
    Concentrate Mixture 3.85 462 2691
    Total 23.85 762 6491

    Calculation for Concentrate Mixture:

    DCP Requirement: 400g

    TDN Requirement: 4200g

    Let CM be the amount of concentrate mixture in kg.

    0.12 * CM = 400g => CM = 400/0.12 = 3333g = 3.33 kg

    0.70 * CM = 4200g => CM = 4200/0.70 = 6000g = 6 kg

    To satisfy DCP, CM needs to be 3.33 kg, but to satisfy TDN, CM needs to be 6 kg. Therefore, we need to adjust the amount of Wheat Straw.

    Since TDN is the limiting factor, we will use 3.85 kg of concentrate mixture to satisfy TDN requirements. The DCP will be slightly higher.

    Nutrient Contribution Summary

    • Wheat Straw: Provides a bulk of the ration and contributes to TDN.
    • Green Berseem: Provides essential nutrients and contributes to both DCP and TDN.
    • Concentrate Mixture: Provides the remaining DCP and TDN to meet the cow’s requirements.

Conclusion

The formulated ration aims to meet the DCP and TDN requirements of the dairy cow, utilizing readily available feedstuffs. The ration comprises a combination of wheat straw, green berseem, and a concentrate mixture, strategically balanced to optimize nutrient intake. Continuous monitoring of milk yield and body condition score is crucial to fine-tune the ration and ensure optimal animal performance. Further research on alternative feed sources and improved ration formulation techniques can contribute to sustainable and efficient dairy farming practices in India.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

TDN (Total Digestible Nutrients)
TDN represents the sum of digestible nutrients in a feed, providing an estimate of its overall energy value for ruminant animals.
DCP (Digestible Crude Protein)
DCP is the portion of crude protein that is digestible by the animal. It is a measure of the protein available for absorption and utilization.

Key Statistics

India is the world's largest milk producer, contributing approximately 38% to global milk production. (Source: FAOSTAT, 2023)

Source: FAOSTAT

The average milk yield per cow in India is around 1,600 kg per lactation, significantly lower than developed countries. (Source: NDDB, 2022)

Source: NDDB

Examples

Integrated Feed Resource Management

Farmers in Gujarat utilize crop residues like wheat straw and maize stover, supplemented with green fodder and concentrates, to provide a balanced ration for their dairy animals.

Dairy Farming in Punjab

Many dairy farmers in Punjab rely heavily on imported soybean meal as a concentrate source, often leading to increased costs and dependence on external markets.

Frequently Asked Questions

Why is TDN more important than DCP in this ration formulation?

TDN represents the total energy available, which is a primary driver of milk production. While DCP is essential for protein synthesis, energy deficiency can severely limit milk yield even with adequate protein.

Can other feedstuffs be substituted in this ration?

Yes, other feedstuffs like maize, groundnut cake, or oilseed cakes can be substituted, but their nutrient composition must be carefully considered to maintain the balance and meet the animal's requirements.

Topics Covered

AgricultureAnimal ScienceLivestock ManagementAnimal NutritionDairy Farming