| More and more attention has been paid to dairy products with the development of social economy and people’s pursuit of higher-quality life.Goat milk is favored by consumers among many kinds of milk because of its rich nutrition and the closest milk composition to human milk.In the process of goat’s milk production,the mammary gland tissue that secretes,stores and discharges milk is extremely important.As an important factor affecting milk production performance,udder shape has been added to the breeding program of large-scale breeding to improve the adaptability to machine milking.The shape of the dairy goat udder is mainly determined by udder morphological data such as udder depth,udder length and udder width.Milk composition,milk yield,mastitis,and udder heritability have been studied more,but few scholars have analyzed their relationship with udder morphological traits in dairy goats,especially udder typing in dairy animals and the mechanisms affecting them.Udder shape,size of udder pool,etc.will affect lactation performance of dairy animals.Therefore,choosing a good udder type in production is particularly important for lactating livestock.This paper explores the effects of different udder types on lactation performance through udder shape typing and udder base typing,combined with the structural characteristics of the central suspensory ligament of the udder,and analyses the internal mechanisms of change in the udder of dairy goats concerning the tension of the central suspensory ligament of the udder and the tissue structure,and draws the following conclusions.1.The udder is divided into square,rectangular and broad udder types,and the udder base is divided into hemispherical and grapefruit types.The different udder types will change as lactation time increases,with the squared udder changing to the oblong type and the hemisphere udder base changing to the teak type;the squared-hemisphere type and the squared-teak type changing to the oblong-teak type.2.Higher milk production in primiparous goats with square and hemispherical udders at 70 th day of lactation;the lactose and total solids content was greater in the wide-flat udder and the total solids content was greater in the grapefruit udder at day 14 of lactation;hemispheric lactose content is greater at 182 days of lactation;no differences between somatic cells of different udder types.Dairy goats with wide flat and grapefruit udders have more variable somatic cell counts and more risk of occult mastitis on day 211 of lactation.3.The central suspensory ligament of the udder is white and runs from the ventral wall of the udder to the base of the udder and is attached to the skin of the udder,with no clear distinction between the two ligaments.The central suspensory ligament of the udder has a high collagen fiber content,is more resilient and stress-resistant,and is less elastic,with a greater variation before and after rupture,which occurs mainly in the middle.In summary,udder type changes with lactation time and tends to vary between long and grapefruit type,with high milk production in dairy goats with square udder types,but long udder teats with long teats and high somatic cell counts are prone to udder infection.The central suspensory ligament in the suspension system does not affect the maximum load,but in a normal udder,the middle part will break first.The above research provides a theoretical basis for improving the udder milk type of dairy goats and for selection and breeding of dairy goats. |
PDF Full Text Request