UPHESC Assistant Professor Animal Husbandry & Dairying 2025 PYQs

Concept: Line breeding is a mild form of inbreeding in which matings are planned to keep a high relationship to an outstanding ancestor (usually a sire).

1. Close breeding = mating of very closely related animals (sire × daughter, full sibs).
2. Top crossing/top breeding = using sires of a different line on an inbred population.
3. Concentrating the blood of one ancestral sire = line breeding.

Short trick: Line breeding = 'keep the LINE of a great ancestor'.

Concept: Heritability (narrow sense) $h^2=V_A/V_P$ – the fraction of phenotypic variation due to additive genes.

1. It ranges from 0 to 1: low (<0.1) for fertility, medium for milk yield (~0.3), high (>0.4) for fat % and body measurements.
2. Gametogenesis, polygenesis and heterogenesis are unrelated terms.

Short trick: $h^2$ = Additive ÷ Phenotypic.

Concept: NDDB began its embryo-transfer (ET) programme in 1987 with the central ET laboratory at Sabarmati Ashram Gaushala (SAG), Bidaj (Gujarat); the first buffalo calf by ET there was born in December 1987.

1. 1985 and 1986 are before the Bidaj ET lab was set up, so they are ruled out.
2. Later milestones: first buffalo calf from a frozen-thawed embryo (1991), first IVF buffalo calf 'Pratham' at NDRI (1990), cloned buffalo 'Samrupa/Garima' at NDRI (2009–10).

Short trick: Bidaj ET → 1987 (year the lab started), calf at year-end: December 1987.

Concept: Repeatability is the correlation between repeated records of the same trait in the same animal (e.g. milk yield in successive lactations).

1. $r=(V_G+V_{Ep})/V_P$ – includes genetic plus permanent environmental variance, so repeatability ≥ heritability.
2. It helps predict an animal's future performance (MPPA) and decide culling.

Short trick: Same animal, same trait, different times = REPEAT-ability.

Concept: NRC (Dairy Cattle, 2001) recommends 0.3 mg Se per kg diet DM for dairy cows in every stage – early, mid and late lactation as well as dry period.

1. 0.3 ppm is also the maximum legal supplementation limit (FDA) in many countries.
2. 1–2 mg/kg would approach toxicity (chronic selenosis: 'alkali disease', hoof and hair loss).

Short trick: Selenium = 0.3 ppm throughout ('Se = 0.3, see?').

Concept: Good hay is green forage dried to about 15% moisture (85% DM) so that it can be stored without moulding or heating.

1. Fresh green fodder has 70–85% moisture; it must be cured down to ~15%.
2. Above 20% moisture, hay heats, moulds and may even catch fire; much below 10–12% leaves shatter and are lost.

Short trick: Hay = 15% moisture; Silage = 65–70% moisture.

Concept: Rennin (chymosin) is secreted by the abomasum (true stomach) of young calves to clot milk; it is not an intestinal enzyme.

1. Lactase, aminopeptidase and nucleosidase are brush-border (intestinal juice/succus entericus) enzymes of the small intestine.
2. Rennin converts casein to paracasein which clots with Ca²⁺, slowing milk passage.

Short trick: Rennin – Rumen-side stomach (abomasum) of calf, not intestine.

Concept: Urea may supply up to one-third of dietary N; the safe ceiling is 1% of total DM (or 2–3% of concentrate), which for an adult cow works out to about 100 g urea per day.

1. Feed it only to adult ruminants (not calves below 6 months) along with readily fermentable carbohydrate (molasses/grain).
2. Introduce gradually and mix uniformly; excess causes ammonia toxicity (bloat, tremors, death).

Short trick: Urea: 1% of DM, 3% of concentrate, ≈100 g/adult/day.

Concept: ICAR/Sen–Ray feeding standard: production requirement for 1 kg buffalo milk (7% fat) is 63 g DCP and 460 g TDN.

1. For 1 kg cow milk (4–4.5% fat) it is about 45–50 g DCP and 315–330 g TDN.
2. Higher fat and SNF in buffalo milk raise its energy content, hence the larger allowance.

Short trick: Buffalo milk: '63–460'; Cow milk: '45–316'.

Concept: Bypass (rumen-undegradable, RUP/UDP) protein escapes microbial breakdown in the rumen and is digested in the abomasum and small intestine.

1. RDP is the opposite – broken down to ammonia by rumen microbes.
2. NPN (urea) is not protein at all.
3. Bypass protein is made by formaldehyde or heat treatment of oil cakes and is useful for high yielders.

Short trick: Bypass = 'escapes' the rumen.

Concept: In Van Soest analysis, NDF = cell-wall constituents = hemicellulose + cellulose + lignin (+ silica). Cell contents (starch, sugars, protein, lipids) dissolve in neutral detergent.

1. ADF = cellulose + lignin (hemicellulose = NDF − ADF).
2. Starch is a cell-content (non-fibre) carbohydrate, so it is not part of NDF.

Short trick: NDF = H + C + L; Starch is 'inside' the cell, not in the wall.

Concept: Methods to upgrade straws are grouped as physical, chemical (urea/NaOH/ammonia), biological (fungi/enzymes) and supplementation.

1. Physical methods listed in standard texts are chopping, grinding/pelleting, soaking and steaming (steam under pressure) – i.e. all four options.
2. Chopping and grinding reduce wastage and increase intake; soaking softens and removes dust/oxalates; steam treatment breaks lignin–carbohydrate bonds.
3. Since more than one (in fact every) option is correct and the question asks for one, it is treated as a bonus.

Short trick: Physical = Chop, Grind, Soak, Steam; Chemical = Urea, NaOH, NH₃.

Concept: Perosis (slipped tendon) – the gastrocnemius tendon slips off its condyle at the hock – is classically due to manganese deficiency in chicks.

1. Choline, biotin, folic acid and niacin deficiencies can also cause perosis, but the mineral cause is Mn.
2. Zinc deficiency → poor feathering, short thick bones; iodine → goitre; cobalt → B₁₂ deficiency.

Short trick: Mn → 'Man-ganese, slipped Man's tendon' = Perosis.

Concept: Too much readily fermentable grain (concentrate > 60% of DM, low fibre) leads to rapid lactic acid production and rumen pH < 5.5 – rumen acidosis.

1. Signs: anorexia, diarrhoea, laminitis, low milk fat.
2. Ketosis is due to negative energy balance; pica to mineral (P) deficiency; grass tetany to Mg deficiency.
3. Keep roughage ≥ 40% of DM and use buffers (NaHCO₃).

Short trick: Excess grain → Acid; Excess fat mobilisation → Ketone.

Concept: Nutritional muscular dystrophy (white muscle disease, stiff-lamb disease) is caused by deficiency of vitamin E (with selenium).

1. Vitamin E/Se protect cell membranes from peroxidation; without them skeletal and cardiac muscle degenerate (chalky white streaks).
2. Vit A → night blindness; Vit D → rickets; Vit C → scurvy (not needed in diet by most livestock).

Short trick: E + Se → White muscle disease.

Concept: Dietary acidifiers (organic acids like citric, fumaric, formic) lower abomasal pH in young calves whose HCl secretion is still low.

1. Lower pH activates rennin/pepsin and speeds clotting of milk casein in the abomasum, improving digestion.
2. They also suppress E. coli and other pathogens, reducing calf scours.
3. Probiotics/yeast act on gut microflora; mould inhibitors only preserve feed.

Short trick: Acidifier → low pH → quick clot → better digestion.

Concept: Barley sprouts (malt sprouts/malt culms, a by-product of malting) contain about 25–28% crude protein.

1. Rice bran ≈ 12–14% CP.
2. Beet molasses ≈ 6–8% CP and citrus molasses ≈ 4–6% CP (mostly NPN) – they are energy feeds.
3. So barley sprouts are the richest in protein.

Short trick: Molasses = sugar (energy), sprouts = protein.

Concept: Correct pairs: Tocopherol (vit E) – crazy chick disease (ii); Riboflavin (B₂) – curled toe paralysis (iv); Choline – slipped tendon/perosis (i); Niacin – black tongue (iii).

1. So the right code is a – ii, b – iv, c – i, d – iii.
2. Option (C) gives b – i and c – iv (riboflavin–slipped tendon, choline–curled toe), which is reversed; (A), (B), (D) are wrong in more pairs.
3. No printed option matches, so the question is treated as a bonus.

Short trick: E – Encephalomalacia (crazy chick); B₂ – curled toe; Choline/Mn – perosis; Niacin – black tongue.

Concept: Favus ('white comb') is a ringworm-type fungal (mycotic) infection of the comb and wattles caused by Microsporum (Trichophyton) gallinae.

1. Coccidiosis – protozoan (Eimeria).
2. Marek's disease – herpes virus.
3. Bumble foot – bacterial (Staphylococcus) abscess of the foot pad.

Short trick: Favus = Fungus (both start with F).

Concept: Rabies vaccines are prepared from 'fixed virus' – street virus serially passaged (Pasteur) in rabbit brain until its incubation period became short and constant (4–6 days).

1. Fixed virus is less virulent for peripheral inoculation and does not form Negri bodies readily.
2. Strains in use: Pasteur virus, PM, CVS, Flury (LEP/HEP), ERA.
3. Street virus is the wild virus from naturally infected animals.

Short trick: Vaccine needs a 'Fixed' (stable) virus.