scholarly journals GENETIC FACTORS AFFECTING TOTAL MILK YIELD, LACTATION PERIOD AND CALVING INTERVAL OF CROSSBRED FRIESIAN COWS RAISED ON NILE DELTA

2019 ◽  
Vol 97 (2) ◽  
pp. 771-784
Author(s):  
SAFAA SANAD ◽  
M. HASSANANE
Keyword(s):  
Milk Yield ◽  
Genetic Factors ◽  
Nile Delta ◽  
Calving Interval ◽  
Lactation Period ◽  
Factors Affecting ◽  
Total Milk ◽  
Friesian Cows

scholarly journals Study on Friesian Herds Raised in Egypt and Germany – II. Genetic and phenotypic trends in estimated transmitting ability

2000 ◽  
Vol 43 (4) ◽  
pp. 399-410
Author(s):  
M. K. Mohsen ◽  
E. S. Tawfik ◽  
A. Y. Salem ◽  
H. G. El-Awady
Keyword(s):  
Total Variation ◽  
Milk Yield ◽  
Original Data ◽  
Genetic Change ◽  
Calving Interval ◽  
Lactation Period ◽  
Genetic Value ◽  
Friesian Cows

Abstract. Original data consisted of 774 first lactation records of daughters of 124 sires of Friesian herds in Egypt and 9219 first lactation records of daughters of 679 sires of Friesian herds in Germany used to estimate genetic and phenotypic trends of initial milk yield in 70 days (IMY), 305-day milk yield (305-dMY), lactation period (LP) and calving interval (CI). Sire component of variance was consistently about 9.88%, 10.75%, 4.63% and 5.03% for IMY, 305-dMY, LP and CI, respectively of the total Variation in Friesian cows in Egypt and about 16.69%, 16.69%, 3.63% and 4.37%, for IMY, 305-dMY, LP and CI, respectively of the total Variation in Friesian cows in Germany. Annual genetic change was 29.98 kg, 112.99 kg, −0.92 d and 1.78 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Egypt and was 70.41 kg, 200.38 kg, 0.12 d and −1.05 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Germany. Annual phenotypic trend was 13.83 kg, 48.00 kg, −1.66 d and −1.82 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Egypt and was 21.00 kg, 104.00 kg, 0.17 d and 0.78 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Germany. The present results show that sires used in the later years were of superior genetic value than those used in the earlier years.

Effect of Breed and Some Non - Genetic Factors on Milk Production and Some Proportions of Its Chemical Components in Two Breeds of Local Sheep

2020 ◽  
Vol 10 (1) ◽  
pp. 227-231
Author(s):  
Rahman Hussein AL-Qasimi ◽  
Shatha Mohammed Abbas ◽  
Allawi L.D. AL-Khauzai
Keyword(s):  
Milk Production ◽  
Genetic Factors ◽  
Chemical Components ◽  
Lactation Period ◽  
Production Traits ◽  
Milk Production Traits ◽  
Fat Percentage ◽  
Awassi Sheep ◽  
Total Milk ◽  
Milk Components

The study was carried out on 19 ewes of local Awassi sheep and 12ewes local Arabi sheep in the Al-kafeel sheep station Karbala, to determine the effect of breed and some non-genetic factors such as (sex of the lamb, type of birth, age and weight of ewes at birth) on daily and total milk production and lactation period and some of milk components (fat, protein and lactose). The results showed that a significant effect (P <0.05) of the breed on milk production traits where Awassi sheep recorded the highest mean (0.91 kg , 101.63 kg , 104.86 day) compared to the Arabi sheep she was means (0.77 kg , 88.15 kg , 99.15 day) respectively. As well as in proportions of milk components with mean( 5.1 , 4.90 , 5.51) % respectively compared to the Arabi sheep (4.70 . 4.20 . 4.89) ewes with male lambs also exceeded superior ewes with female lambs in daily and total milk production and the lactation period the sex of the lamb did not affect the proportions of milk components the weight of the ewes had a significant effect (P <0.05) in milk production attributes with superior weight of ewes on lower ewes and did not affect the proportions of milk ingredients except for lactose. The type of birth and the age of the ewes did not have a significant effect in all the studied traits except for the superiority (P<0.05) of young ewes on age ewes in the fat percentage of milk.

scholarly journals Modelling of the lactation curve of grazing Mongolian mare

2020 ◽  
Vol 29 (1) ◽  
pp. 64-71
Author(s):  
Sandagdorj Badrakh ◽  
Baigalmaa Tserenpil ◽  
Burenjargal Sedkhuu ◽  
Nyam-Osor Purevdorj
Keyword(s):  
Mathematical Models ◽  
Milk Yield ◽  
Lactation Period ◽  
Linear Quadratic ◽  
Quartic Curve ◽  
Lactation Curve ◽  
Total Milk ◽  
Curve Model ◽  
Composition Curve ◽  
Best Fit

Current research was performed to determine the yield and composition of milk during entire lactation period, which lasts June to February of following year and describe fit of lactation curve using different mathematical models. Total 8 mares, aged from 5 to 12 years were used in the study. The total milk yield, calculated by Fleischmann's method, as well as the models were various and shape of curves for Linear, Quadratic, Cubic, and Quartic equations, and Wood's curve were different. The determination index (R2) of the milk yield and composition curve models ranged from 0.474-0.987, and R2 of Quartic curve model for milk yield (0.987) was the highest. Study result showed that the above models were able to describe the lactation curve of the milk yield and composition, and the Quartic model best fit to data collected from Mongolian mare and allowed a suitable description of the shape and dynamics of curve. Бэлчээрийн маллагаатай Монгол гүүний лактацын муруйн загварчлал Монгол гүүний саалийн нийт хугацаанд буюу VI сараас дараа жилийн III сар хүртэл саамны гарц, найрлагын хэмжээг үндэслэн математик загваруудаар лактацын муруй байгуулах, монгол гүүний лактацын муруйд хамгийн нийцэл сайтай загварыг сонгон тодорхойлох зорилгоор энэхүү ажлыг хийж гүйцэтгэлээ. Судалгаанд 5-12 насны 8 гүүг ашиглав. Сүүний нийт гарц, найрлагын хэмжээг Вүүд (Wood’s)-ын загвар болон шугаман, шугаман бус регрессын тэгшитгэлээр загварчлахад лактацын муруйн загварууд харилцан адилгүй байв. Саамны гарц, найрлагын муруйн загваруудын детерминацийн индекс (R2) нь 0.474-0.987-ийн хооронд хэлбэлзэж, биквадрат загварын хувьд хамгийн нийцэл өндөр буюу 0.987 байв. Судалгааны үр дүнд дээрх аргуудаар саамны гарц, найрлагын лактацын муруйг загварчлах боломжтой нь харагдаж байсан ба эдгээрээс биквадрат тэгшитгэлийн загвар нь  бэлчээрийн маллагаатай монгол гүүний саамны өгөгдөлтэй хамгийн сайн нийцэж, лактацын муруйн хэлбэр, хөдлөлзүйн хувьд тохирч байв.   Түлхүүр үг: саамны гарц, саамны найрлага, лактацын муруй  

scholarly journals Effect of Some Non-Genetic Factors on 305-day Milk Yield and Lactation Persistency in Holstein Friesian Cows

2021 ◽  
Vol 40 (2) ◽  
pp. 189-194
Author(s):  
Zienab Abo-Gamil ◽  
Hadeel El-Qaliouby ◽  
Eman Manaa ◽  
Sherif Ramadan
Keyword(s):  
Milk Yield ◽  
Genetic Factors ◽  
Holstein Friesian ◽  
Friesian Cows

Characterisation of the Lactation Curve in Pakistani Buffaloes

1984 ◽  
Vol 1984 ◽  
pp. 136-136
Author(s):  
K.Z. Gondal ◽  
P. Rowlinson
Keyword(s):  
Milk Yield ◽  
Indian Subcontinent ◽  
Human Consumption ◽  
Dairy Herds ◽  
Lactation Period ◽  
General Shape ◽  
Or Groups ◽  
Lactation Curve ◽  
Total Milk ◽  
Dairy Animals

The rate of milk secretion in dairy animals displays a trend throughout the lactation period. It increases to a maximum in a few weeks following parturition and decreases thereafter until the animal goes dry.This trend draws a certain curve, namely the lactation curve.The milk yield of a single lactation may be influenced by many factors but the general shape of the lactation curve defined by the locus of weekly yields remains substantially unchanged. It rises rapidly to the peak within a few weeks after calving followed by a more or less gradual decline until the end of lactation.The analysis of the lactation curve, i.e. the week to week output of milk and trend of increase and decrease in yield with advancement of lactation is important for day to day management and forward planning of dairy herds by reliable forecasting of week by week milk production, seasonal variation and the total milk yield of individual cows or groups of cows.A number of reports pertaining to dairy cattle have been published but very few studies have been concerned with buffaloes. In most of the countries, the buffaloes have been used for draught purpose but it is in the Indian subcontinent that this animal is seen at its greatest advantage as a source of animal protein, i.e. milk and meat for human consumption.

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