Bleeding

To prevent the risk of recovery, animals must be bled as soon as possible after stunning, ideally whilst still in the tonic (rigid) phase. Bleeding involves severing the carotid arteries and jugular veins, or the blood vessels from which they arise. The animal then dies from loss of blood. It is important that all major blood vessels are severed. If only one carotid artery is cut the animal may take over a minute to die.

Abattoir methods

Cattle, deer and horses

Bleeding should be carried out by an incision made with a sharp knife in the jugular furrow at the base of the neck, the knife being directed towards the entrance of the chest to sever all the major blood vessels arising from the heart (Figure 23). In the interest of good hygiene two knives should be used, the first to open the skin and the second to sever the blood vessels. This procedure is often referred to as 'sticking'.

Figure 23: Bleeding cattle

Sheep and Goats

Bleeding may be carried out in a similar way as for cattle (Figure 24-1) or by an incision made close to the head using a blade at least 120mm long to sever both carotid arteries and both jugular veins, i.e. a cut across the throat (Figure 24-2). In the EU, the trachea and oesophagous of animals intended for human consumption must remain intact during bleeding, except in the case of slaughter according to a religious custom. An incision at the entrance to the chest must therefore be used (Figure 24-1).

Figure 24: Bleeding sheep

Pigs

A knife at least 120mm long should be inserted in the mid-line of the neck at the depression before the breast bone, and the skin raised with the knife point using light pressure and a lifting movement. When penetration has been made, the knife handle should be lowered so that the blade is in a near-vertical position, and pushed upward to sever all the major blood vessels which arise from the heart (Figure 25).

Figure 25: Bleeding pigs

Field and emergency killing methods

In the field or emergency situation, the most practical method of bleeding is to make a deep transverse cut across the animal’s throat at the angle of the jaw. Cut deeply, severing the blood vessels, trachea and oesophagus, until the blade of the knife touches the spine (Note: animals bled using this method will not be permitted for human consumption in the EU). There should be two powerful jets of blood from the carotid arteries, and a flow from the jugular veins (Figure 26). The heart may continue to pump until the carcase is exsanguinated. To carry out this task effectively, the operator needs a sharp knife with a blade at least 120mm long.

Figure 26: Cross-section of neck

Stun-to-stick intervals

The stun-to-stick interval is the time from application of stunning equipment to the start of bleeding. A maximum stun-to-stick interval of 15 seconds is recommended for all species in the field. In the abattoir, all pigs, sheep and goats should also be stuck within 15 seconds. However, on the majority of cattle lines, where the carcase must be hoisted to a bleed area, maximum stun-to-stick intervals of 60 seconds for the penetrative captive-bolt and 30 seconds for the non-penetrative captive-bolt are acceptable. It is essential that equipment is well maintained and that stunning is carried out accurately, using the correct cartridge, to ensure that animals are effectively and irreversibly stunned.

Next: Pithing