UPSC Mains Answer PYQ 2024: Animal Husbandry Paper 1 (Section- A) | Animal Husbandry & Veterinary Science Optional for UPSC PDF Download

Section A

(a) Write about how secretion of hormones from anterior pituitary gland is regulated in animals? (10 Marks)
Ans: The anterior pituitary gland (adenohypophysis) plays a crucial role in regulating growth, metabolism, reproduction, and lactation in animals. Its hormone secretion is tightly controlled to maintain homeostasis, mainly through feedback mechanisms involving the hypothalamus and target organs.

• Hypothalamic Control:

• The hypothalamus produces releasing hormones (e.g., TRH, GnRH, CRH) and inhibitory hormones (e.g., somatostatin, dopamine).

• These hormones are transported via the hypothalamo-hypophyseal portal system to the anterior pituitary.

• Negative Feedback Mechanism:

• Hormones secreted by target organs (e.g., cortisol from adrenal gland, thyroxine from thyroid) inhibit further secretion by the anterior pituitary.

• Example: High levels of cortisol suppress ACTH release.

• Positive Feedback Mechanism:

• Less common but important during specific conditions like ovulation.

• Example: Pre-ovulatory surge of estrogen stimulates LH surge.

• Neuroendocrine Reflex:

• Involves sensory inputs influencing hormone secretion.

• Example: Suckling stimulus in dairy cows leads to increased prolactin secretion.

• Pulsatile Secretion: Hormones like GnRH and LH are secreted in pulses to maintain receptor sensitivity and physiological effects.

Examples:

• In dairy cattle, proper functioning of anterior pituitary hormones like prolactin and GH is crucial for optimal milk production.
• In poultry, FSH and LH regulate egg-laying cycles.

The anterior pituitary gland functions under a highly coordinated regulatory system involving hypothalamic control, feedback mechanisms, and external stimuli. Understanding this regulation is critical for improving productivity and health in animal husbandry.

(b) Discuss in brief about the physiological adjustment of camel in hot desert. (10 Marks)
Ans: Camels, often called the "ships of the desert," exhibit remarkable physiological adaptations that enable survival in extreme desert environments where high temperatures and scarce water pose severe challenges.

• Water Conservation Mechanisms:

• Ability to tolerate 30% dehydration without ill effects.

• Highly concentrated urine and dry feces to minimize water loss.

• Thermoregulation:

• Variable body temperature ranging from 34°C to 41.7°C, reducing the need for evaporative cooling.

• Thick coat insulates against daytime heat and nighttime cold.

• Fat Storage: Hump stores fat, not water. Fat metabolism yields metabolic water.

• Respiratory Adaptations: Nasal counter-current mechanism minimizes water loss during breathing.

• Efficient Water Intake: Can drink up to 100 liters of water in a few minutes when available.

• Blood Adaptation: Oval-shaped RBCs allow flow even during dehydration.

Examples: Dromedary camels used in Rajasthan for transportation and dairy production survive extreme desert conditions with minimal water requirements.

The physiological adaptations of camels to conserve water, tolerate heat, and store energy enable their survival and utility in desert ecosystems, making them invaluable for animal husbandry in arid regions.

(c) Mention about the advantages and disadvantages of information and communication technology (I.C.T.) into animal husbandry. (10 Marks)
Ans: Information and Communication Technology (ICT) has significantly transformed animal husbandry by improving access to information, management practices, and veterinary services. However, it also presents certain challenges.
Advantages:

• Efficient Record Keeping: Digital apps for managing livestock health, breeding records, and productivity (e.g., e-Pashuhaat portal).
• Access to Veterinary Services: Telemedicine enables remote veterinary consultations, especially in rural areas.
• Market Access: Farmers can access real-time market prices and sell products through online platforms.
• Education and Training: Mobile apps and e-learning platforms educate farmers on nutrition, breeding, and disease management.
• Early Disease Warning: ICT enables rapid reporting and response to disease outbreaks (e.g., Foot and Mouth Disease alerts).

Disadvantages:

• Digital Divide: Limited internet access in remote rural areas hampers benefits to small farmers.
• Data Privacy Concerns: Misuse of sensitive farm and livestock data by third parties.
• High Initial Costs: Setting up ICT infrastructure can be expensive for marginal farmers.
• Dependency on Technology: Over-reliance may reduce traditional skills and resilience.

Examples:

• Mobile applications like mKisan and Pashu Poshan have helped dairy farmers access feed formulations.
• Some remote areas in North-East India still face difficulties in ICT adoption.

While ICT has immense potential to revolutionize animal husbandry by enhancing efficiency and access to information, addressing challenges like digital infrastructure and literacy is crucial for equitable benefits across the sector.

(d) Discuss about the protein efficiency ratio. (10 Marks)
Ans: Protein Efficiency Ratio (PER) is an important biological measure of protein quality. It is particularly crucial in animal husbandry to ensure that feedstuffs meet the protein requirements of livestock and poultry for optimal growth, reproduction, and production.
Definition:

• PER is defined as the gain in body weight per gram of protein consumed.
• Formula: PER = Protein intake (g) / Weight gain of the animal (g)$\frac{}{}\backslash text\{PER\}\; =\; \backslash frac\{\backslash text\{Weight\; gain\; of\; the\; animal\; (g)\}\}\{\backslash text\{Protein\; intake\; (g)\}\}$

Significance:

• Evaluates the quality of dietary proteins based on their ability to promote growth.
• Essential for formulating rations, especially in poultry, piggery, and aquaculture industries.

Procedure:

• Young, growing animals (usually rats or chicks) are fed a test diet.
• Their weight gain over a specific period is measured relative to protein intake.

Types of PER:

• Net Protein Ratio (NPR): Adjusts PER by considering weight loss in control animals.
• Adjusted PER: Corrects PER values to standard protein (casein) levels.

Applications in Animal Husbandry:

• Designing high-protein feed supplements for dairy cattle to enhance milk yield.
• Improving broiler chicken feed to maximize weight gain in minimum time.

Limitations:

• PER primarily reflects growth, not maintenance or reproductive efficiency.
• It may overestimate protein quality in fast-growing animals but not reflect protein needs of adult or pregnant animals.

Examples:

• Soybean meal has a high PER and is extensively used in poultry rations.
• Cottonseed meal, despite high protein content, has a lower PER due to presence of anti-nutritional factors like gossypol.

Protein Efficiency Ratio serves as a critical parameter in evaluating and formulating animal feeds to enhance growth and productivity. However, it must be complemented with other measures like Biological Value (BV) and Digestibility Coefficient for a comprehensive understanding of protein quality.

(e) Describe Weende method of feed analysis. (10 Marks)
Ans: The Weende Method, also known as Proximate Analysis, is the oldest and most widely used method for evaluating the chemical composition of animal feeds. Developed at the Weende Experiment Station in Germany (Henneberg and Stohmann, 1860), it forms the foundation of animal nutrition analysis.
Components Analyzed:

• Moisture Content: Water present in the feed; affects storage and nutritive value.
• Crude Protein (CP): Estimated by measuring nitrogen content and multiplying by 6.25.
• Ether Extract (EE): Represents fat content extracted by solvents.
• Crude Fibre (CF): Indigestible fiber portion like cellulose and lignin.
• Ash: Total mineral content obtained after burning the feed.
• Nitrogen-Free Extract (NFE): Readily digestible carbohydrates like sugars and starches.

Procedure:

1. Dry the sample to determine moisture content.
2. Digest another portion in acid and alkali to estimate crude fiber.
3. Extract fat using ether.
4. Burn the residue to calculate ash.
5. Calculate NFE by difference.

Significance in Animal Husbandry:

• Helps in designing balanced rations for livestock and poultry.
• Assists in quality control of commercial feeds.

Advantages:

• Simple, cost-effective, and standardized globally.
• Provides a basic nutritional profile for feed evaluation.

Limitations:

• Does not distinguish between digestible and indigestible fiber fractions.
• Overestimates true protein content by assuming all nitrogen comes from protein.

Examples: Used routinely in analyzing green fodder, silage, and compound feed formulations for cattle and goats.

The Weende method remains a cornerstone of feed analysis in animal husbandry due to its simplicity and reliability. However, for more precise evaluation, especially of fiber and protein quality, modern techniques like Van Soest’s detergent analysis are increasingly used alongside.

Q2: 
(a) Describe the measurement of energy retention by carbon-nitrogen balance technique. (15 Marks)
Ans: Energy retention measurement is essential to understand the efficiency of nutrient utilization in animals. The Carbon-Nitrogen (C-N) balance technique is a biological method used to estimate retained energy based on the measurement of carbon and nitrogen inputs and outputs.
Principle:

• Based on the conservation of mass, particularly of carbon (C) and nitrogen (N), within the animal's body.
• Intake of C and N from feed and loss through excreta, respiration, and exhalation are measured.

Procedure:

• Carbon Intake: Measure total carbon content in the feed.
• Carbon Output: Measure carbon lost through feces, urine, and CO₂ exhaled.
• Nitrogen Intake: Analyze nitrogen in the feed consumed.
• Nitrogen Output: Determine nitrogen lost through urine, feces, and minor routes.

Calculation:

• Retained Carbon = Carbon intake – (Carbon in feces + Carbon in urine + Carbon in expired CO₂)
• Retained Nitrogen = Nitrogen intake – (Nitrogen in feces + Nitrogen in urine)
• Energy Retention is calculated based on the retained carbon and nitrogen, considering the energy equivalents of protein and fat synthesized.

Energy Equivalents:

• 1 g protein = 23.6 kJ
• 1 g fat = 39.3 kJ

Advantages:

• Non-invasive.
• Provides information on both energy and protein metabolism.

Limitations:

• Requires accurate collection of excreta and gas.
• Minor gaseous nitrogen losses (e.g., ammonia) may cause slight errors.

Examples:

• Used in growing lambs to determine energy retention for optimizing feeding strategies.
• Poultry nutrition research utilizes the method for balancing high-efficiency broiler diets.

The Carbon-Nitrogen balance technique offers a reliable and practical method for measuring energy retention in animals, crucial for feed formulation, growth performance analysis, and improving livestock production efficiency.

(b) What is "growth curve"? Describe the different stages of growth curve in animals. (5 + 15 = 20 Marks)
Ans: The growth curve represents the graphical relationship between the age of an animal and its body weight or size over time. Understanding the growth pattern is fundamental for improving production efficiency in livestock and poultry.
Definition: 
​A growth curve is a sigmoid (S-shaped) curve that illustrates the stages of growth from birth to maturity.

Stages of Growth Curve:

1. Prenatal Stage:

   • Development of tissues and organs before birth.

   • Nutritional management of pregnant dams crucial for fetal growth.

2. Initial Postnatal Stage (Lag Phase): Slow growth rate immediately after birth due to immature digestive and metabolic systems.

3. Accelerated Growth Phase (Log Phase):

   • Rapid body weight gain.

   • High feed conversion efficiency.

   • Example: Broilers reach market weight quickly during this phase.

4. Decelerated Growth Phase:

   • Growth rate slows as maturity approaches.

   • Muscle growth stabilizes; fat deposition increases.

5. Maturity Phase:

   • Growth ceases; maintenance requirements dominate.

   • Production focus shifts to reproduction and lactation.

Factors Affecting Growth Curve:  Genetics, nutrition, health status, environment, and management.

Examples: 
​In dairy calves, growth monitoring is done using standardized growth charts to ensure future high milk production potential.

Understanding the stages of the growth curve allows animal husbandry practices to be tailored for optimal growth rates, feed efficiency, and economic returns in livestock production.

(c) Write about the nutrient requirement of chicken. (15 Marks)
Ans: Poultry production efficiency relies on providing chickens with balanced nutrients tailored to their physiological stages — growth, egg-laying, or broiler production. Nutrient requirements are dynamic and vary by age, breed, and purpose (meat or egg).
Major Nutrient Requirements:

1. Energy:

   • Provided mainly through cereals like maize, wheat.

   • Broilers require high-energy diets (~3000 kcal ME/kg) for rapid growth.

2. Protein:

   • Crucial for muscle development and egg production.

   • Broilers need 22-23% crude protein (starter phase), while layers require around 18%.

3. Vitamins:

   • Vitamin A (vision, immunity), Vitamin D₃ (calcium absorption), and Vitamin E (reproduction) are critical.

   • Deficiencies lead to poor growth, weak eggshells, or rickets.

4. Minerals:

   • Calcium and Phosphorus: Important for bone formation and eggshell quality.

   • Inclusion of dicalcium phosphate or limestone in diets.

5. Fats:

   • Enhance energy density and supply essential fatty acids.

   • 3-5% fat inclusion is typical in broiler diets.

6. Water:

   • Often neglected, but vital.

   • Clean, cool water is essential for metabolic processes.

Specific Needs at Different Stages:

Feed Additives: Use of probiotics, prebiotics, and enzymes for improved nutrient absorption.

Examples:

• Commercial broiler breeds like Cobb 500 require precision feeding to maximize weight gain.
• Indigenous breeds require slightly lower nutrient density.

Proper nutrient management tailored to the developmental stage and purpose (meat or eggs) of chickens is vital for maximizing production efficiency, ensuring bird health, and enhancing farm profitability.

Q3: 
(a) Describe about the copper-molybdenum-sulphur inter-relationship in ruminants. (15 Marks)
Ans: Copper (Cu), molybdenum (Mo), and sulphur (S) have a complex interrelationship affecting mineral metabolism in ruminants. Their balance is crucial for maintaining normal physiological functions like enzyme activity, immune response, and growth.
Normal Functions:

• Copper: Required for hemoglobin formation, connective tissue synthesis, and immunity.
• Molybdenum: Component of enzymes like xanthine oxidase.
• Sulphur: Essential for sulfur-containing amino acids and vitamins (e.g., biotin, thiamine).

Interrelationship:

• Antagonistic Interaction: High dietary Mo and S together can reduce Cu absorption in the gastrointestinal tract.

• Thiometallate Complex Formation:

  • In the rumen, Mo and S combine to form thiomolybdates.

  • Thiomolybdates bind copper and make it unavailable for absorption.

Consequences:

• Copper Deficiency: Even when dietary Cu is adequate, high Mo and S can cause "secondary copper deficiency."
• Clinical signs include anemia, poor coat quality ("steely wool" in sheep), lameness, diarrhea, and decreased immune function.

Optimum Ratios:

• Ideal Cu:Mo ratio = 6:1 to 10:1 in the diet.
• High sulphur (>0.3%) intensifies copper deficiency risk.

Management Strategies:

• Supplementation with organic copper sources.
• Reducing dietary molybdenum and sulphur content.
• Use of injectable copper preparations in severely deficient animals.

Examples: In grazing cattle in molybdenum-rich soils (e.g., reclaimed coal mining areas), secondary copper deficiency is common.

Understanding the intricate copper-molybdenum-sulphur interaction is vital for preventing metabolic disorders, optimizing growth, and ensuring health in ruminants. Balanced mineral supplementation is essential for efficient animal production.

(b) Write in detail about the components of circulatory system in animals. (15 Marks)
Ans: The circulatory system in animals is responsible for transporting nutrients, gases, hormones, and waste products throughout the body. It plays a critical role in homeostasis, immunity, and thermoregulation.
Major Components:

1. Heart:

   • Muscular organ that pumps blood.

   • In mammals and birds: Four-chambered heart (two atria, two ventricles).

2. Blood Vessels:

   • Arteries: Carry blood away from the heart under high pressure.

   • Veins: Return blood to the heart.

   • Capillaries: Thin-walled vessels where nutrient and gas exchange occurs.

3. Blood:

   • Composed of plasma (fluid part) and formed elements (RBCs, WBCs, platelets).

   • RBCs carry oxygen via hemoglobin; WBCs defend against infections.

4. Lymphatic System:

   • Includes lymph, lymph nodes, and lymph vessels.

   • Assists in tissue fluid balance and immune responses.

Circulatory Patterns:

• Pulmonary Circulation: Blood flow between heart and lungs for oxygenation.
• Systemic Circulation: Blood flow between heart and rest of the body.

Functions:

• Transport of oxygen, carbon dioxide, nutrients, hormones.
• Removal of metabolic wastes (e.g., urea, CO₂).
• Thermoregulation by adjusting blood flow to the skin.

Examples: ​In dairy cows, proper blood circulation is crucial for effective milk synthesis in mammary glands.

The circulatory system is vital for sustaining life and ensuring physiological equilibrium in animals. Understanding its structure and function is essential for diagnosis and treatment of various systemic disorders.

(c) Explain about the feeding of breeding bulls. (10 Marks)
Ans: Proper feeding of breeding bulls is crucial for maintaining optimal fertility, libido, and overall reproductive performance. Nutrition influences semen quality, vigor, and longevity.
Nutrient Requirements:

1. Energy:

   • Maintenance energy to avoid obesity or excessive leanness.

   • Grains like maize and barley can be provided in moderate amounts.

2. Protein:

   • Adequate protein (12–14% CP) is necessary to maintain muscle mass and sperm production.

3. Minerals and Vitamins:

   • Zinc, selenium, and Vitamin E are vital for sperm motility and integrity.

   • Calcium and phosphorus important for bone health.

4. Roughage:

   • Good quality green fodder (e.g., Lucerne, berseem) should form a significant part of the diet.

Feeding Strategy:

• Avoid overfeeding energy-dense feeds which can lead to obesity and reduced libido.
• Maintain a body condition score (BCS) of around 3–3.5 (on a scale of 5).

Special Considerations:

• During breeding season, slightly increase energy intake to support activity.
• Clean drinking water must be available at all times.

Examples: Breeding bulls in artificial insemination centers are fed a carefully balanced ration to ensure high-quality semen production.

Optimal feeding of breeding bulls ensures reproductive efficiency, enhances semen quality, and prolongs the breeding life of valuable sires, directly influencing livestock productivity.

(d) Discuss about the use and abuse of antibiotics as feed additives in swine feeding. (10 Marks)
Ans: Antibiotics have been used as growth promoters and disease preventatives in swine feeding for decades. However, their indiscriminate use poses serious concerns regarding antibiotic resistance and food safety.
Use of Antibiotics:

• Improve feed efficiency and growth rates.
• Prevent subclinical infections.
• Enhance gut health and nutrient absorption.
• Common antibiotics: Tylosin, chlortetracycline, bacitracin.

Abuse of Antibiotics:

• Overuse leads to antibiotic-resistant bacteria (e.g., MRSA).
• Residual antibiotics in meat can affect human health.
• Disturbance of gut microflora leading to dysbiosis.

Regulations and Alternatives:

• Many countries, including the EU, have banned antibiotic growth promoters.
• Alternatives: Probiotics, prebiotics, organic acids, phytogenics (plant extracts).

Best Practices:

• Use antibiotics only under veterinary prescription.
• Observe withdrawal periods before slaughter.
• Employ good biosecurity measures to reduce infection risk.

Examples:  ​The U.S. swine industry has shifted towards antibiotic-free labels in response to consumer demand and public health concerns.

While antibiotics can enhance swine production efficiency, their misuse threatens animal and public health. Judicious use, adherence to guidelines, and exploring natural alternatives are critical for sustainable pig farming.

Q4: 
(a) Describe the various blood biochemical tests and discuss their importance in health status of animals. (20 Marks)
Ans: Blood biochemical tests are essential diagnostic tools used to assess the health status, organ function, and metabolic profile of animals. They provide critical information to veterinarians for early disease detection, monitoring therapy, and evaluating nutritional status.
Major Blood Biochemical Tests:

1. Liver Function Tests (LFTs):

   • Enzymes: ALT (Alanine aminotransferase), AST (Aspartate aminotransferase), ALP (Alkaline phosphatase).

   • Bilirubin levels (total and direct).

   • Importance: Diagnose liver diseases like hepatitis, fatty liver syndrome in cows.

2. Kidney Function Tests (KFTs):

   • Blood Urea Nitrogen (BUN), Creatinine.

   • Importance: Assess renal efficiency; detect conditions like nephritis.

3. Glucose Test:

   • Blood glucose concentration.

   • Importance: Detects metabolic disorders like ketosis in dairy cows or diabetes in pets.

4. Total Protein, Albumin, Globulin:

   • Importance: Reflects nutritional status, liver function, and chronic infections.

5. Electrolyte Analysis:

   • Sodium, potassium, chloride, calcium, and phosphorus levels.

   • Importance: Imbalances can indicate dehydration, metabolic disorders, or parturient paresis.

6. Lipid Profile:

   • Cholesterol, triglycerides.

   • Importance: Indicates metabolic disorders and energy balance in high-producing animals.

7. Mineral Analysis:

   • Serum magnesium, zinc, copper levels.

   • Importance: Diagnoses deficiencies leading to disorders like grass tetany.

Importance of Biochemical Tests:

• Early diagnosis and prevention of diseases.
• Monitor therapy progress.
• Assess stress, reproductive health, and performance status.
• Guide diet formulation for optimized health.

Examples:

• Hypocalcemia (milk fever) is confirmed by low serum calcium levels in recently calved dairy cows.
• Elevated AST and low albumin suggest hepatic lipidosis in fat cows during early lactation.

Blood biochemical tests are indispensable for comprehensive health evaluation and management of animals. Regular biochemical monitoring ensures better disease prevention, higher productivity, and animal welfare.

(b) Classify antinutritional factors with suitable examples. (15 Marks)
Ans: Antinutritional factors (ANFs) are naturally occurring or synthetic compounds in feedstuffs that interfere with the digestion, absorption, or utilization of nutrients. Their management is vital for improving feed efficiency and animal health.
Classification of Antinutritional Factors:

1. Protein Inhibitors:

   • Examples: Trypsin inhibitors (soybean, groundnut).

   • Effect: Interfere with protein digestion by inhibiting proteolytic enzymes.

2. Lectins (Hemagglutinins):

   • Examples: Raw legumes like kidney beans.

   • Effect: Bind to gut mucosa, causing reduced nutrient absorption.

3. Tannins:

   • Examples: Sorghum, Acacia leaves.

   • Effect: Bind and precipitate proteins, reducing digestibility.

4. Phytates:

   • Examples: Cereal grains, oilseeds.

   • Effect: Bind minerals like calcium, zinc, and iron, making them unavailable.

5. Oxalates:

   • Examples: Spinach, beet greens.

   • Effect: Form insoluble complexes with calcium, leading to deficiency.

6. Cyanogenic Glycosides:

   • Examples: Cassava, linseed.

   • Effect: Release cyanide on hydrolysis, causing toxicity.

7. Goitrogens:

   • Examples: Brassica species (cabbage, rapeseed).

   • Effect: Inhibit thyroid hormone synthesis.

8. Saponins:

   • Examples: Alfalfa.

   • Effect: Reduce feed intake and cause digestive disturbances.

Management Strategies:

• Heat processing (e.g., roasting soybean) to destroy trypsin inhibitors.
• Supplementation with enzymes like phytase to counter phytates.
• Plant breeding to develop low-ANF varieties.

Examples:

• Roasting soybean meal significantly reduces trypsin inhibitor activity, making it suitable for poultry and pig diets.
• Feeding cassava must involve proper processing to eliminate cyanide risk.

Understanding the types and effects of antinutritional factors is critical for formulating balanced, safe diets for animals. Strategic processing and supplementation help in minimizing the negative impacts of ANFs on animal productivity.

(c) Give the diagrammatic representation of kidney. (15 Marks)
Ans: The kidney plays a crucial role in excretion, osmoregulation, and maintenance of acid-base balance in animals. Understanding its anatomical structure through diagrammatic representation aids in better comprehension of its physiological functions.
Diagram of the Kidney:

​​Important Parts to Label:

• Renal Capsule
• Renal Cortex
• Renal Medulla (with Renal Pyramids)
• Renal Columns
• Minor and Major Calyces
• Renal Pelvis
• Ureter

Brief Explanation:

• Renal Capsule: Tough outer covering protecting the kidney.
• Renal Cortex: Outer region containing nephrons for filtration.
• Renal Medulla: Inner region with renal pyramids facilitating urine concentration.
• Minor Calyces: Collect urine from pyramids.
• Major Calyces: Formed by the union of minor calyces.
• Renal Pelvis: Funnel-shaped basin collecting urine into the ureter.
• Ureter: Transports urine to the bladder.

Examples:

• In poultry, kidneys are lobulated and elongated, adapted for uric acid excretion.
• In cattle, kidneys are lobulated externally, unlike the smooth surface seen in horses.

Diagrammatic understanding of kidney anatomy is essential for appreciating its vital excretory and regulatory roles in animal physiology, aiding in effective disease diagnosis and treatment planning.