STRUCTURE OF MAMMARY GLAND (UDDER) SS1 (SECOND PAGE)

The mammary gland or udder is a large and succulent organ surrounded by the skin. It is attached to the body of the animal by ligament. It is made up of large duct which empty their content into a large cistern. It terminate with an alveoli from where milk is secreted. The contraction of the alveoli lead to milk let down.
DRAW AND LABEL THE STRUCTURE OF A MAMMARY GLAND
The mammary gland is made up of smooth muscle, sympathetic and sensory nerves number of glands varies with farm animals. The major equipment use for milk extraction from the mammary gland is called the milking machine. The main substance extracted by the milking machine from the udder of cow, ewe and doe is milk.the process by which this substance is collected with the milking machine is made fit for human consumption is called pasteurisation.
ECONOMIC IMPORTANT OF MILK

• It is a source of protein in food
• It can be used in raising foster calves, lamb or children
• It is used in the preparation of baby food
• It supplies minerals to livestock
• It is used as extender in artificial insemination practices
  COLOSTRUM
  This is the first milk produced immediately after the parturition. In the first five days of milk production colostrum is produced and it is important for young ones to consume. It is yellowish white, produced immediately after birth and it contain some antibodies against diseases to which the mother has been exposed.it is rich in protein, especially albumin and globulins, it also contains vitamin A, E and B2.
  FLUSHING
  Flushing in animal production is the condition in which extra feed rich in nutrients is given to female animals some days before mating. This is to enable farm animal produce more eggs or ova.
  MALE REPRODUCTIVE SYSTEM
  The male reproductive system includes the testes which produces spermatozoa and sex hormones called testosterone which aids the development of male secondary characteristics. The spermatozoa is produced in the seminiferous tubules of the testes during meiotic cell division by a process called spermatogenesis. The testes are contain in a scrotal sac ( Scrotum) outside the abdominal cavity to enable them produce sperm cell at desire temperature.
  DRAW AND LABEL THE REPRODUCTIVE ORGANS OF A CATTLE
  The epididymis ensure sperm maturation and storage in the testes. The testes are connected to the uterus masculinus by vas deferens which transport sperm from testes to the uterus masculinus where mature spermatozoa are stored until they r released during coitus or mating. Blood vessels called spermatic cords supply supply nutrients and oxygen to the testes. Along the urethra are accessory glands which are the Cowper’s gland, seminal vesicle and prostate. They produce slimy alkaline fluid which aids the movement of spermatozoa. This fluid together with the spermatozoa resulting in the formation of semen. The urethra is a uro-genital organ which helps to inject sperms into the vagina and also the removal of urine. The urethra ends externally in the penis.
  FEMALE REPRODUCTIVE SYSTEM
  The female reproductive system includes the ovaries which produces the ova or ovum enclosed by the graffian follicle and some hormones such as the oestrogen.
  DRAW AND LABEL THE FEMALE REPRODUCTIVE SYSTEM OF EWE
  A mature egg is released from the follicle in the ovary into the oviduct.This process is called ovulation. As the egg is released from the ovary, the female animal comes into heat and she is willing to mate with the male animal.
  Fertilisation is the fusion between the male and female sex cell to form a zygote. When the egg is fertilized, it anchor itself to the wall of the uterus and this process is called Implantation. The development of foetus take place in the uterus. Below the uterus is the vagina which receives the sperm during copulation.
  DEVELOPMENT OF THE EMBRYO (FOETUS)
  The fertilized egg is implanted in the uterus where the development of the embryo takes place. Embryonic membranes develop round the embryo. These are the chorion, the allantois and the yolk sac. The amnion forms a sac in which the embryo lies and is filled with amniotic fluid. Hence the embryo is held in a liquid environment which serves as buffer or shock absorber. The allantois form a sac which is excretory, respiratory and nutritive in function. It contribute to the formation of placenta. The yolk sac provides the food during the early stages of the pregnancy. The chorion forms the outermost membrane, enveloping all this structure.
  The placenta establishes an intimate connection between the embryo and the mother which aids nutritional, respiratory and excretory needs of the embryo. The placenta and the embryo are connected by the umbilical cord which develope from the allantois. The parental blood supply is linked to the foetal blood supply through the umbilical cord. At the end of the gestation period, the animal gives birth.