5. SUMMARYThe study was carried out in the Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig, Egypt, during the years 1992-2004. The study was on Holstein Friesian cows imported to Egypt and Jordan . In Egypt, the study included: 1. Comparison between the imported cow traits at the first parity in farms situated in different localities. 2. Comparison between imported and locally born cattle at the first parity. 3. Comparison between the imported cows at first parity in Jordan. 4. Comparison between the imported cows at first parity in each of Egypt and Jordan. 5. Anoestrus due to galactorrhea in milk high yielder cows and its improvement, were also studied. In Jordan, effects of some environmental factors on productive and reproductive traits, were studied. 6. Milkability (milking traits) in a Jordan farm .The study also included aThe results can be summarized as follows:Comparison between the different farms in Egypt1. The temperature-humidity index values indicated exposure of Holstein Friesian cows to severe heat stress during summer and spring seasons, in Egypt.2. Farm affected significantly (P3. Year of birth affected significantly (P4. Season of birth affected significantly (P5. Year of calving affected significantly (P6. Season of calving affected significantly (P7. Classes of age at first calving affected significantly (P940 days.8. Classes of days open affected significantly (PComparison between the imported and locally born Holstein cows at first parity, in Egypt1. The temperature-humidity index values indicated exposure of the Holstein cows to sever heat stress during summer season, in Egypt.2. The imported dams (in Dina farm) showed lower values (P3. Year of birth affected significantly (P4. Season of birth affected significantly (P5. Year of calving affected significantly (P6. Season of calving affected significantly (P7. Classes of age at first affected insignificantly all traits studied.Cow traits newly imported Friesian, in Jordan1. The THI values indicated absence of heat stress during winter and autumn and exposure to severe heat stress during summer in Jordan farm.2. Effects of parity were significant (P,0.001 or 0.05) on days open, number of inseminationS per conception, milk yield and calving interval. The shortest values in days open and calving interval were recorded in the fourth parity. The lowest number of inseminationS per conception and the highest milk yield were also recorded in the fourth parity.3. Season of calving affected significantly (P4. Sex of calf and type of birth affected insignificantly the traits studied.5. classes of milk yield affected significantly (P6. Classes of lactation period affected significantly (P500 days. The shortest dry period was recorded in the class 300 – 500 days, while the shortest calving interval accompanied the class7. Classes of days open affected significantly (PComparison between the imported Holstein cows at first parity, in Egypt and Jordan1. Farm affected dry period, lactation period, calving interval and milk yield significantly (P2. Year of calving affected significantly (P3. Season of calving affected significantly (P4. The shortest dry period, lactation period and calving interval accompanied the class 124 days.5. The shortest dry period was shown with the class 6000-12000kg milk and lactation period were shown with the class 12000 kg milk.6. The shortest calving interval was shown with the class 500 days.Milking traits (Milkability)1. Pregnant cows were higher significantly (P2. Season of year (sampling), parity and daily level of milk yield on milk flow, peak milk flow, milking duration and milk yield, were highly significant (P3. Milk flow and peak milk flow were significantly higher (P4. Milk flow in the first parity, peak milk flow in the second parity and milking duration and milk yield in the fifth parity were significantly (P5. The first level (11.0 kg) of average daily milk yield in the herd showed the highest (P6. Birth of male calves was accompanied with the highest (P7. Single births were accompanied with the highest (PAnoestrus due to galactorrhea in imported Holstein Friesian cows and its improvement, in Egypt1. The body weight and age at first service differed insignificantly between normal and anoestrous cows.2. Length at the 1st, 2nd and 3rd lactations and the post-partum period were significantly (P3. The correlation coefficient values between post-partum period and body weight at first service, were negatively significant (P4. Cervical mucus ferning, glycogen, inorganic phosphate, water, sodium, potassium and zinc values were significantly (P5. Treatment of anoestrus cows with different doses of Bromocriptine increased ferning, glycogen, inorganic phosphate, water, sodium, potassium and zinc values, but decreased spin-barkeit, ER and pH in anoestrous cows.6. Incidence of conception in anoestrous cows at a rate of 76.5% (13/17) after administration of 75 µg/kg body weight Bromocriptine indicates that such injection prevented the metabolic disorders.Diseases1. The vaccination must be regarded as an aid in the prevention of the diseases.2. The mastitis infections showed highly in the year 1993 than the year 1994 and the percentages of scour infections was 31.0% and respiratory infections 3.0% in a sample of dairy calves.