Maharashtra HSC Animal Science & Technology cheat sheet

Animal science integrates genetics, nutrition, physiology, health, housing, and economics into livestock production; the classic triad is breeding, feeding, and management.

Livestock production systems: extensive (pasture/range, low input), semi-intensive (partial stall feeding plus grazing), intensive (confined, high input), and integrated crop-livestock systems that recycle manure and crop residues.

Ruminants (cattle, buffalo, sheep, goats) ferment feed in the rumen via microbes; non-ruminants (pigs, poultry) rely on enzymatic digestion in the stomach and small intestine.

India's livestock sector contributes about 4-5% of national GDP and roughly 25-30% of agricultural gross value added; milk is the single largest livestock product by value.

Maharashtra livestock profile: cattle and buffalo dominate dairying, goats and sheep are important in rain-shadow districts, and poultry is concentrated near urban markets.

Terms: livestock census (quinquennial count), exotic vs indigenous breeds, and the distinction between a breed (stable heritable type) and a strain (selected line within a breed).

Production indices: milk yield per animal per lactation, dressing percentage, egg production per hen housed, and feed conversion ratio convert biological output into comparable units.

Common livestock production goals: food security, draught power, manure, hides and skins, wool, and household income diversification.

Ruminant stomach has four compartments: rumen (fermentation vat), reticulum (hardware/fermentation), omasum (water absorption, leaves), abomasum (true gastric digestion).

Rumen physiology: pH 6.0-7.0 on forage diets, drops below 5.5 in subacute ruminal acidosis; microbes produce volatile fatty acids (acetate, propionate, butyrate) plus microbial protein.

Vital signs: cattle respiration 10-30/min, rectal temperature 38.0-39.3 C, pulse 60-80/min; buffalo and small ruminants are broadly similar with slight variation.

Estrus cycle: cattle and buffalo 18-24 days (average 21), sheep 16-17 days, goats 18-22 days; estrus lasts roughly 12-18 hours in cattle.

Vaccination calendar: FMD, HS (haemorrhagic septicaemia), BQ (black quarter), anthrax, brucellosis (calfhood), PPR in sheep and goats, and Ranikhet disease (Newcastle) in poultry.

Notifiable/important diseases: FMD, rinderpest (historically), anthrax (zoonotic), brucellosis (zoonotic), mastitis, foot rot, and avian influenza.

Deworming schedule: strategic deworming at 3-4 week intervals in young stock, and pre-monsoon and post-monsoon in adults; rotate anthelmintic classes to slow resistance.

Anatomy landmarks: rumen located left, abomasum right-ventral; the left flank is the surgical approach for rumenotomy and caesarean section.

Proximate analysis fractions: moisture, crude protein (N x 6.25), ether extract, crude fibre, nitrogen-free extract, and ash; total digestible nutrients (TDN) summarise energy.

Rumen microbes need a nitrogen source, energy, minerals, and buffering; urea can supply non-protein nitrogen up to about 1% of concentrate, never in the drinking water.

Ration balancing rule: match protein and energy to production stage; a lactating cow needs roughly 1 kg concentrate per 2.5-3 kg milk above maintenance.

Feed categories: roughages (green fodder, dry fodder, silage, hay) and concentrates (cereal grains, oil cakes, bran); mineral mixture and common salt are mandatory supplements.

Silage making: harvest at 60-70% moisture, chop, compact, exclude air, and ensile; good silage pH is about 3.8-4.5 with a lactic acid smell.

Anti-nutritional factors: gossypol in cottonseed cake, trypsin inhibitor in raw soybean, tannins in tree leaves, and prussic acid in immature sorghum/jowar.

Water requirement: cattle drink roughly 3-5 litres per litre of milk plus maintenance; water restriction is a common hidden cause of low milk yield.

Feed conversion ratio (FCR) = feed consumed / product output; lower FCR means better efficiency, and broiler FCR is typically 1.5-1.8.

Inheritance basics: qualitative traits (coat colour, horns) are controlled by few genes; quantitative traits (milk yield, growth) are polygenic and influenced by environment.

Selection methods: mass selection, progeny testing (sires), family selection, and index selection; heritability (h2) expresses the fraction of phenotypic variation that is genetic.

Crossbreeding exploits heterosis (hybrid vigour); common Indian examples include Holstein Friesian x Sahiwal (HF cross) and Jersey x Red Sindhi.

Artificial insemination (AI): semen collected, diluted, frozen in liquid nitrogen at -196 C, and deposited in the cervix or uterine body at the correct time of estrus.

Breeding soundness: age at first calving target 24-30 months in crossbred cattle; calving interval target 12-13 months; service period about 60-90 days.

Pregnancy diagnosis in cattle and buffalo: rectal palpation from about 45-60 days, transrectal ultrasonography earlier, and progesterone or estrone sulphate tests.

Buffalo reproduction is characterized by silent heat and seasonal breeding tendency; the Murrah is the premier milk breed with high fat content.

Inbreeding depression reduces fertility and vigour; line breeding and outcrossing are used to manage inbreeding in small herds.

Lactation curve: yield rises to a peak at 6-8 weeks after calving, then declines; the dry period of about 60 days before calving is required for udder regeneration.

Milking hygiene: wash and dry udder, fore-strip to check for mastitis, use pre- and post-dip, and keep a consistent milking interval of 12 hours.

Mastitis detection: California Mastitis Test (CMT) and somatic cell count; subclinical mastitis is the main economic loss.

Clean milk production targets: total bacterial count below 50,000 cfu/ml for good raw milk, and methylene blue reduction test time above 5 hours.

Calf rearing: colostrum within the first 2 hours (about 10% of body weight), then whole milk or milk replacer, calf starter from 2 weeks, and weaning at 8-12 weeks.

Buffalo management: buffaloes are wallowers, need shade and water, have lower heat tolerance, and their milk typically contains 6-8% fat versus 3.5-4.5% in cattle.

Housing for dairy: loose housing with a loafing area or tail-to-tail stanchion barn; floor slope 1:40 to 1:60 for drainage; 40-50 sq ft covered space per cow.

Economics: cost of milk production per litre includes feed (60-70%), labour, and overheads; reducing the dry period and improving peak yield lower the cost per litre.

Incubation: chicken eggs hatch in 21 days at 37.5-37.8 C dry bulb and 55-60% relative humidity, with turning and cooling practices in forced-draft incubators.

Brooding: chicks need 32-35 C in the first week, reduced about 3 C per week until ambient; floor space about 0.5 sq ft per bird in brooding and 1 sq ft in grow-out.

Layer management: lighting of 14-16 hours stimulates lay; peak production around 26-30 weeks; feed about 110-120 g per bird per day.

Broiler targets: market weight 1.8-2.2 kg in 5-6 weeks, FCR 1.5-1.8, and mortality under 5% in a well-managed flock.

Vaccination schedule: Marek's at day-old, Ranikhet (Newcastle) at day 7 and 28, IBD (Gumboro) at day 14 and 21, and fowl pox at 6-8 weeks.

Common diseases: Ranikhet (Newcastle disease), infectious bursal disease, coccidiosis, chronic respiratory disease, and avian influenza (zoonotic).

Poultry housing systems: deep litter (rice husk or sawdust), cage system, and slatted floor; deep litter needs 6-8 cm litter depth and regular turning.

Egg quality: albumen index, Haugh unit (higher is fresher), yolk colour from carotenoids, and shell strength; eggs are graded by weight and shell cleanliness.

Goat breeds: Sirohi, Beetal, Jamunapari (milk), and Boer (meat); sheep breeds: Deccani, Nali, Marwari (wool and meat), and Merino (fine wool).

Goats browse and select feed; they need about 4-6% of body weight in green fodder and are highly susceptible to internal parasites, so rotational grazing matters.

Sheep wool growth: fibre diameter determines quality; shearing is done once or twice a year, and wool yield per adult sheep is roughly 1-2 kg per year.

Swine: gestation 114 days, litter size 8-12, weaning at 4-6 weeks; pigs are monogastric and need balanced protein, with lysine as the first limiting amino acid.

Pig breeds: Large White Yorkshire, Landrace, Duroc, and Hampshire; Indian local pigs include Ghungroo and Niang Megha.

Backyard poultry: indigenous breeds such as Aseel, Kadaknath, and Vanaraja provide low-input household protein and are more disease-tolerant than commercial hybrids.

Rabbit and duck farming: rabbits are hindgut fermenters with a gestation of about 31 days; ducks need water for bathing and lay 150-250 eggs per year depending on breed.

Small ruminant health: PPR vaccination, enterotoxaemia (ET) vaccination before monsoon, and regular deworming are core preventive measures.

Milk composition: water about 87%, lactose 4.5-5%, fat 3.5-6%, protein 3.2-3.5%, and minerals about 0.7%; buffalo milk is higher in fat and solids-not-fat.

Pasteurization: HTST at 72 C for 15 seconds or LTLT at 63 C for 30 minutes; sterilization is above 100 C; UHT at 135-150 C for 2-4 seconds gives a long shelf life.

Milk tests: Gerber method for fat, Kjeldahl for protein, lactometer for specific gravity, and methylene blue or resazurin reduction for microbial quality.

Milk products: butter, ghee, paneer, cheese, curd, khoa, and milk powder; ghee is clarified butterfat with a characteristic flavour from diacetyl and free fatty acids.

Meat: rigor mortis sets in 2-6 hours post-slaughter and resolves during aging; pH declines from about 7.0 to 5.5-5.7 in normal muscle.

Dressing percentage = (carcass weight / live weight) x 100; typical values are 50-55% in cattle, 45-50% in buffalo, and 65-75% in pigs.

Wool grading uses fibre diameter (micron), staple length, crimp, and medullation; fine wool is under 25 microns, and medullated (kemp) fibre lowers value.

By-products: hides and skins for leather, bones for gelatin and bone meal, blood meal, tallow, horns and hooves for buttons and glue, and manure for biogas and compost.

Cost of production per litre of milk = total annual cost / total annual milk yield; feed alone typically accounts for 60-70% of the cost.

Gross margin = gross income minus variable costs; fixed costs (land, buildings, equipment) are excluded from the gross margin calculation.

Benefit-cost ratio = total discounted benefits / total discounted costs; a ratio above 1 indicates a viable project.

Payback period = initial investment / annual net cash inflow; shorter payback means quicker recovery of capital.

Marketing channels: producer to consumer direct sale, producer to cooperative to processor, and producer to village milk collector to chilling centre.

Milk cooperatives (Amul pattern) pool milk, provide input services, and pay a price based on fat and SNF content; the Anand pattern is a three-tier structure.

Entrepreneurship supports: NABARD, NABARD's Dairy Entrepreneurship Development Scheme, state livestock development boards, and bank credit under priority sector lending.

Insurance and risk: livestock insurance covers death from disease and accident; premium is subsidised under government schemes for small and marginal farmers.

Site selection: elevated, well-drained land, near water and feed sources, away from residential areas, with all-weather road access and room for expansion.

Space norms for cattle: 40-50 sq ft covered area and 80-100 sq ft open area per adult; calves need about 20-25 sq ft covered space.

Ventilation: ridge opening in the roof, side curtains, and a minimum air exchange to remove moisture and ammonia; ammonia above 25 ppm harms respiratory health.

Floor slope of 1:40 to 1:60 with a gutter for drainage; a non-slip surface prevents injuries, and a manger height of about 40-45 cm suits adult cattle.

Biosecurity: controlled entry, footbaths, quarantine of new animals for 30 days, all-in-all-out where possible, and rodent and bird control.

Disinfection: use a suitable disinfectant at the correct dilution; organic matter reduces efficacy, so clean before disinfecting.

Farm records: breeding register, milk register, feed and fodder register, health and treatment register, and financial ledger; records drive decisions and loan applications.

Waste management: manure pit or compost bed, biogas plant from dung, and proper disposal of dead animals by deep burial or incineration to prevent disease spread.