(a) Describe the procedure for conducting post-mortem examination of a cow in a vetero-legal case. (20 marks) (b) Give a…

(a) Procedure of post-mortem examination of a cow in a vetero-legal case (20 marks)

A vetero-legal post-mortem is done to establish the cause and manner of death for the courts, in cases such as poisoning, cruelty (Prevention of Cruelty to Animals Act, 1960), killing or maiming of an animal (BNS section 325, old IPC 428 and 429), unlawful slaughter, electrocution, and disputed insurance claims.

Preliminaries:

• Act only on a written requisition from the police, court or other competent authority, and record the date, time, place and those present, including two witnesses.
• Identify the animal by species, breed, sex, age, colour, marks and ear tag, and note the history, the time of death and the circumstances.
• Suspect anthrax in sudden death with oozing dark, unclotted blood: do not open the carcass, and take a peripheral blood smear from an ear vein instead.
• Do the examination in daylight as early as possible, before decomposition, wearing gloves and protective clothing, with photographs at each stage.

External examination: rigor mortis and decomposition, bloat, wounds (site, size, type), ligature or rope marks, discharges from orifices, colour of the mucous membranes, and hooves, skin, udder and ectoparasites.

Internal examination:

1. Lay the cow on its left side, so that the rumen lies below, and cut the skin from chin to pubis.
2. Reflect the skin and examine the subcutaneous tissue for haemorrhage and oedema, then remove the upper limbs.
3. Open the abdomen and examine the organs in position (fluid, torsion, peritonitis), then open the chest and examine the pleura, pericardium, heart and lungs.
4. Remove and examine each organ in turn: the rumen and reticulum (odour of poison, foreign bodies), abomasum, intestines, liver, spleen, kidneys, bladder and uterus (pregnancy), then the brain.

Sample collection: take rumen contents, liver, kidney, blood, urine and brain (about 500 g each of the solid samples) in clean separate containers with saturated salt solution as preservative, never formalin, for toxicology, and 10% formalin for histopathology. Label, seal and hand over with a chain-of-custody record to the forensic laboratory.

Report: give a signed written report of the findings, with an opinion on the cause, mode and probable time of death, to the requisitioning authority; keep a copy, be ready to give evidence in court, and dispose of the carcass by deep burial with lime or incineration.

(b) Processing of Cheddar cheese with flow diagram, and its nutritive value (20 marks)

Cheddar is a hard, ripened cheese made from cow or buffalo milk, and its name comes from the "cheddaring" stage.

Process, as shown in the flow diagram. Milk is standardised to 3.5 to 4% fat with a casein to fat ratio of about 0.7, pasteurised at 72 °C for 15 seconds and cooled to 30 to 31 °C in the cheese vat. A starter of 1 to 2% Lactococcus lactis subsp. cremoris and lactis is added with annatto colour and, if needed, calcium chloride (0.02%), and the milk is ripened for 30 to 45 minutes. Rennet (chymosin) is added, and the milk sets in 30 to 40 minutes. The coagulum is cut into 6 to 8 mm cubes, the curd is stirred and cooked slowly to 38 to 39 °C over 30 to 40 minutes to shrink it and expel whey, and the whey is drained at about pH 6.2. In cheddaring the curd mat is cut into slabs which are turned and piled for 1 to 1.5 hours until the pH is 5.2 to 5.3, giving a fibrous texture. The curd is milled to finger-size pieces, salted at 2 to 2.5%, filled into hoops and pressed for about 16 hours. The cheese is dried and waxed or vacuum-packed, and ripened at 6 to 10 °C for 3 to 12 months or longer, when proteolysis and lipolysis develop flavour and texture. The yield is about 10 kg per 100 kg of milk.

Nutritive value. As per the FSSAI and Codex standard, Cheddar has at most 39% moisture and at least 48% fat in its dry matter. Per 100 g it gives about 400 kcal, about 25 g of high-quality protein rich in essential amino acids, about 33 g of fat, and only traces of lactose, since it is lost in the whey and fermented. It is an excellent source of calcium (about 700 mg) and phosphorus, and of vitamin A, vitamin B12 and riboflavin. Salt, saturated fat and energy are high, so intake should be moderate.

(c) Uses of animal organs and glandular by-products for food and pharmaceuticals (10 marks)

Food:

• Liver, heart, kidney, tongue and tripe are eaten as offal, being rich in iron, vitamin A, B12 and folate.
• Blood is used in blood products; bones give soups and stock; fat gives lard and tallow; gelatin and collagen casings come from skin, bones and intestine.

Pharmaceuticals:

• Pancreas: insulin (now largely recombinant), pancreatin, trypsin and chymotrypsin.
• Intestinal mucosa and lung: heparin.
• Stomach: pepsin; calf abomasum gives rennet.
• Pituitary: ACTH, oxytocin and vasopressin; thyroid: thyroxine extract; adrenal: adrenaline and corticoids; ovary and testis: sex hormones and hyaluronidase.
• Liver and bile: liver extracts and bile acids.
• Cartilage: chondroitin sulphate; intestine: catgut sutures; porcine heart valves for implants.