UPHESC Assistant Professor Animal Husbandry & Dairying 2025 PYQs

Concept: Glanders (Burkholderia mallei) is a notifiable zoonosis of equids. The OIE (WOAH) Terrestrial Animal Health Code (chapter on infection with B. mallei) lays down that an equid imported from a country or zone not free from glanders must have been isolated for at least 30 days before shipment and tested negative on two samples taken 21 to 30 days apart.

1. So the recommended isolation (quarantine) period is 30 days; 21 days is only the minimum gap between the two tests, not the quarantine period.
2. 45, 28 and 14 days do not appear in the OIE provisions either.
3. The correct figure, 30 days, is not among the printed options, so no option is correct and the question is treated as a bonus.

Short trick: Glanders (OIE): isolate 30 days, two tests 21–30 days apart.

Concept: Carcasses suspected of anthrax must not be opened: exposure to air makes Bacillus anthracis form resistant spores that contaminate soil for decades.

1. Diagnosis is made from a blood smear from an ear vein (polychrome methylene blue – McFadyean reaction).
2. Carcass is burnt or buried deep with lime.
3. Rabies, TB, botulism (or bloat) cases may be necropsied with precautions.

Short trick: Anthrax: 'Don't open – spores will spread'.

Concept: Negri bodies are eosinophilic intracytoplasmic inclusion bodies in neurons (Purkinje cells of cerebellum, hippocampus pyramidal cells) – pathognomonic of rabies.

1. Seen with Seller's stain; today FAT is the gold standard.
2. FMD and rinderpest are viral but do not form Negri bodies; anthrax is bacterial.

Short trick: Negri → Neurons → Rabies.

Concept: Hog cholera (classical swine fever) is caused by a Pestivirus (family Flaviviridae).

1. It is highly contagious, with fever, haemorrhages ('turkey-egg' kidney), button ulcers in the colon and splenic infarcts.
2. Controlled by live attenuated lapinised vaccine (IVRI).

Short trick: Hog cholera = Pestivirus (like BVD, Border disease).

Concept: Haemorrhagic septicaemia (Pasteurella multocida B:2) is a bacterial disease; its vaccines are bacterins – alum-precipitated or oil-adjuvant – not tissue-culture vaccines.

1. Enterotoxaemia: multicomponent clostridial toxoid – correct.
2. Black quarter: polyvalent (Cl. chauvoei + Cl. septicum) – correct.
3. Anthrax: Sterne live spore vaccine – correct.
4. Tissue-culture vaccines are for viral diseases (e.g. rinderpest, PPR).

Short trick: Bacteria → bacterin; Virus → tissue culture.

Concept: Human milk is whey-dominant and lactose-rich compared with cow milk.

1. Lactose: human ≈ 7.0% vs cow ≈ 4.8%.
2. Whey : casein = about 60 : 40 in human milk vs 20 : 80 in cow milk; whey protein (α-lactalbumin, lactoferrin) is the larger share in human milk.
3. Casein, total protein and ash are much higher in cow milk.

Short trick: Human milk: more sugar, more whey; Cow milk: more casein, more minerals.

Concept: The critical control point in an HTST plant is the pasteurisation step itself – the holding time–temperature (72 °C/15 s) reached after the final heating section, monitored at the holding tube and flow-diversion valve.

1. This step eliminates pathogens; failure cannot be corrected later.
2. Before final heating the milk is not yet pasteurised; after cooling, temperature is a storage control (prerequisite), not the kill step.

Short trick: CCP = the 'kill step' → after final heating (holding tube).

Concept: Vanaspati and margarine in India must contain 5% sesame (til) oil as a marker; the Baudouin test (furfural + HCl → crimson/pink colour with sesamolin) detects it.

1. Hotis test – mastitis (streptococci) in milk.
2. Resorcinol (Seliwanoff) test – sucrose/added sugar.
3. Hehner's test – formalin in milk.

Short trick: Vanaspati → Sesame → Baudouin (pink).

Concept: The US FDA published its Seafood HACCP regulation (21 CFR Part 123) in December 1995; it came into force in December 1997.

1. USDA's meat & poultry HACCP (Pathogen Reduction rule) followed in 1996.
2. Juice HACCP came in 2001.
3. HACCP itself was developed by Pillsbury with NASA in the 1960s.

Short trick: Seafood 1995 → Meat 1996 → Juice 2001.

Concept: Dissolved lactose and salts depress the freezing point of milk below that of water; normal bovine milk freezes at about −0.525 to −0.565 °C (average −0.54 °C).

1. It is the most constant property of milk, so it is used (cryoscope) to detect added water.
2. Every 1% added water raises the freezing point by about 0.0055 °C.
3. Positive temperatures (1–3.5 °C) cannot be a freezing point of an aqueous solution.

Short trick: Milk freezes at ≈ −0.55 °C; closer to 0 = watered milk.

Concept: β-Lactoglobulin is the major whey protein of cow milk, about 50% of whey protein (≈ 9–10% of total protein); in the classical Indian dairy-chemistry tables it is given as about 0.28 g per 100 g milk.

1. Whey proteins ≈ 0.6–0.7 g/100 g milk; about half of this is β-Lg (≈ 0.3 g).
2. α-Lactalbumin ≈ 0.12, serum albumin ≈ 0.04, immunoglobulins ≈ 0.07 g/100 g.
3. 0.38–0.40 would be more than half of all whey protein, 0.20 too little; 0.28 fits best.

Short trick: β-Lg ≈ half of whey protein ≈ 0.3 g%; it is absent from human milk.

Concept: Warm-milk separation is done at about 35–40 °C (≈ 40 °C), where fat is liquid and milk viscosity is low, so separation efficiency is best.

1. Stokes' law: rate ∝ $({\rho }_s-{\rho }_f)r^2/\eta$ – heating lowers viscosity $\eta$.
2. Higher temperatures (> 45–50 °C) favour foaming and fat-globule damage; cold separation needs special separators.

Short trick: Separate cream at ≈ 40 °C (body-warm milk).

Concept: An emulsifier (mono- and diglycerides, polysorbate 80, lecithin) has both hydrophilic and hydrophobic groups, so it sits at the fat–water interface and holds the two phases together.

1. It also gives dryness and smooth texture by controlled fat destabilisation during freezing.
2. Stabilisers (gelatin, CMC, guar, carrageenan) bind water and check ice-crystal growth – they do not join fat to water.

Short trick: Emulsifier = 'two-faced' molecule (water-loving + fat-loving).

Concept: PER = weight gain (g) ÷ protein consumed (g) in growing rats. Casein, the reference protein, gives a PER of about 2.7–2.8 (adjusted to 2.5 for the ANRC standard).

1. Whey proteins / lactalbumin have higher PER (≈ 3.0–3.6) because they are richer in sulphur amino acids and lysine.
2. Total milk protein ≈ 2.8–3.1; casein is lowest among milk proteins owing to limiting methionine + cystine.

Short trick: Casein ≈ 2.7–2.8 < Milk protein ≈ 3.0 < Whey ≈ 3.2–3.6.

Concept: As per the Indian standard (IS 1166 / PFA–FSSAI), sweetened condensed milk must have not less than 9% milk fat and not less than 31% total milk solids (sugar extra, ~40–45%).

1. Unsweetened (evaporated) milk: fat ≥ 8%, total milk solids ≥ 26%.
2. Sweetened condensed skimmed milk: milk solids ≥ 26%, fat ≤ 1%.

Short trick: SCM: 9% fat + 31% milk solids ('9-31').

Concept: After pasteurisation and homogenisation (≈ 63–70 °C) the mix must be cooled at once – over a surface/plate cooler – to a low temperature and then aged at 0–5 °C for 4–24 h.

1. Quick cooling prevents bacterial growth and fat clumping and prepares the mix for ageing.
2. Of the given values only the lowest, 14 °C, lies in the cooling range; 24–44 °C are near incubation temperatures for bacteria.
3. Final ageing temperature is about 4 °C.

Short trick: Ice-cream mix: hot homogenise → cool fast → age cold (≈ 4 °C).

Concept: Fishy flavour in (especially salted, ripened-cream) butter arises when lecithin breaks down to choline and then trimethylamine, aided by acidity, salt and copper/iron.

1. Lactulose and HMF are heat-induced (Maillard) markers in milk.
2. Diacetyl gives the desirable buttery aroma; excess gives harsh 'coarse' flavour, not fishy.

Short trick: Fishy = TMA (same compound that makes fish smell).

Concept: Under FSSAI, 'ice cream' must contain only milk fat (≥ 10% for ice cream); vegetable fat/oil cannot be added.

1. A product made with vegetable fat must be labelled 'Frozen Dessert/Frozen Confection', not ice cream.
2. Medium-fat ice cream ≥ 2.5% and low-fat ice cream ≤ 2.5% milk fat – again only milk fat.

Short trick: Veg fat → not ice-cream but 'Frozen Dessert'.

Concept: PFA (now FSSAI) standard: whole milk powder – moisture ≤ 4%, milk fat ≥ 26%, titratable acidity ≤ 1.2% (as lactic acid).

1. Partly skimmed milk powder: fat 1.5–26%.
2. Skimmed milk powder: fat ≤ 1.5%, moisture ≤ 5%.

Short trick: WMP: '4% moisture, 26% fat'.

Concept: For Cheddar-type cheese, milk is standardised to a casein : fat ratio of about 0.68–0.72 (≈ 0.70), giving the legal fat-in-dry-matter (≈ 50%) and good body.

1. Too little casein (low ratio) → greasy, weak-bodied cheese with high fat loss.
2. Too high a ratio → hard, dry cheese with low FDM.
3. Corresponding protein : fat ratio ≈ 0.85–0.9.

Short trick: Cheddar milk: Casein/Fat ≈ 0.7.