(a) Write about the feeding of swine for lean meat production and its importance in human health. (10+5 marks) (b) Discuss about…

(a) Feeding of Swine for Lean Meat and Its Importance in Human Health Lean carcass depends on directing nutrients to protein deposition rather than fat. The main levers are:

• Energy-to-protein balance: use lean genotypes (Large White Yorkshire, Landrace, Duroc crosses) and a high lysine-to-energy ratio. Lysine, then methionine and threonine, are the limiting amino acids, so balance them with soybean meal or fishmeal and synthetic amino acids, giving about 18–20% crude protein in starters, 16–18% in growers and 14–16% in finishers.
• Phase feeding: because protein need per unit of feed falls with age, move from starter to grower to finisher diets, ideally with split-sex feeding, so surplus energy is not stored as fat.
• Energy control: limit digestible energy in the finisher (bulky ingredients such as bran or restricted feeding) and avoid excess added fat or maize.
• Feed conversion efficiency, clean water, and use of beta-agonists (e.g., ractopamine) only where legally permitted.

Importance for health: lean pork has less total and saturated fat and cholesterol, so it suits dietary guidance for cardiovascular risk. It gives high-quality protein with all essential amino acids, abundant thiamine (B1), B12, haem iron and zinc, nutrients commonly short in cereal-based Indian diets. Compared with fatty cuts it gives more protein per calorie, helping tackle protein deficiency and obesity.

(b) Blood Coagulation in Pigs Coagulation is the conversion of soluble fibrinogen to insoluble fibrin, through a cascade of clotting factors, most of them synthesised in the liver.

Primary haemostasis: vessel injury causes vasoconstriction, and platelets adhere through von Willebrand factor and collagen and form a plug.

Extrinsic pathway: tissue factor (III) from damaged tissue activates factor VII. Intrinsic pathway: contact with exposed collagen activates XII, then XI, then IX; IXa with VIIIa (activated by thrombin) forms the tenase complex. Both pathways converge on X. Xa with Va, calcium and platelet phospholipid forms prothrombinase, which converts prothrombin (II) to thrombin. Thrombin converts fibrinogen to fibrin and activates XIII, which cross-links the fibrin into a stable clot.

Factors II, VII, IX and X need vitamin K (hence warfarin-poisoning in pigs), and calcium is factor IV. Clot retraction and fibrinolysis by plasmin follow. Porcine von Willebrand disease is a recognised inherited defect. PT tests the extrinsic and APTT the intrinsic pathway.

(c) Natural Antioxidants and Their Role in the Animal Body Natural antioxidants are substances of dietary or endogenous origin that, at low concentration, delay or prevent oxidation of lipids, proteins and DNA by scavenging free radicals and reactive oxygen species. They fall into non-enzymatic (vitamin E, vitamin C, beta-carotene, glutathione, polyphenols and flavonoids) and enzymatic types (superoxide dismutase, catalase, glutathione peroxidase, which depends on selenium).

Roles:

• Protect cell membranes from lipid peroxidation: vitamin E, lipid-soluble, breaks the chain reaction in the membrane, and vitamin C regenerates it.
• Maintain immunity: neutrophil and lymphocyte membranes are shielded from their own oxidative burst, so disease resistance and vaccine response improve.
• Support fertility: they protect sperm and oocyte membranes and early embryos from oxidative stress; vitamin E-selenium deficiency causes white muscle disease, retained placenta and reduced fertility.
• Reduce heat-stress and mastitis damage, and improve meat quality by slowing rancidity and drip loss.
• Prevent cellular ageing and inflammation.

Synthetic antioxidants (BHA, BHT) are the contrast.

(d) Male Reproductive Organs of the Bull

Functions: testes make sperm (at 4–6°C below body temperature, regulated by the pampiniform plexus and cremaster) and testosterone; the epididymis matures and stores sperm; the accessory glands add fructose, citric acid and buffers; the sigmoid flexure straightens on erection for intromission.