Comparing biological and linear models to estimate milk yields and lactation curve parameters

2005 ◽  
Vol 2005 ◽  
pp. 113-113
Author(s):  
B. Albarran-Portillo ◽  
G. E. Pollott
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Linear Models ◽  
Computational Effort ◽  
Reasonable Accuracy ◽  
Early Predictors ◽  
Lactation Curve ◽  
Total Milk ◽  
Mathematical Equations

The genetic evaluation of dairy cows is based primarily on milk production and its constituents. Many models have been developed and evaluated in order to estimate total milk yield (CTMY) and other characteristics of lactation curves. Frequently, the models are based on complex mathematical equations and their use demands a huge computational effort. The development of simple models as early predictors of TMY with a reasonable accuracy is important. The objective of this research was to compare the biological model described by Pollott (2000) with two linear models.

The use of short-term secretion rate measurements for estimating the milk production of suckler cows

1978 ◽  
Vol 45 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Y. L. P. Le Du ◽  
R. D. Baker ◽  
J. M. Barker
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Composition ◽  
Secretion Rate ◽  
Short Term ◽  
Beef Cow ◽  
Total Milk ◽  
Fat Yield ◽  
Good Agreement

SummaryTwo experiments with dairy cows and one with suckler cows and their calves were conducted to examine the use of secretion rate measurements for estimating total milk production. In the first experiment both 4- and 6- h intervals between measurements gave similar estimates of total 7-d milk yield. The second experiment compared estimated and measured milk composition as well as yield. Milk and solids-not-fat yields were underestimated with dairy cows as a result of an extended milking interval before measurement. However, fat yield was overestimated, indicating that all residual milk was not removed at the first oxytocinaided milking. It was concluded that for the beef cow, previous interval effects would be eliminated by the frequency of calf suckling, but that residual milk effects might cause a 3–6% and a 16% overestimation of milk and fat yields respectively.In the third experiment, the milk yield of suckler cows was estimated from measurements of secretion rate and from changes in calf weight; good agreement was obtained provided there were at least 3 consecutive controlled sucklings.

scholarly journals Comparison of the parameters of the lactation curve between normal and difficult calvings in Iranian Holstein cows

2019 ◽  
Vol 17 (1) ◽  
pp. e0401
Author(s):  
Navid Ghavi Hossein-Zadeh
Keyword(s):  
Dairy Cows ◽  
Milk Yield ◽  
Goodness Of Fit ◽  
Linear Models ◽  
Information Criterion ◽  
Holstein Cows ◽  
Coefficient Of Determination ◽  
Lactation Curve ◽  
Non Linear ◽  
Best Fit

To evaluate effect of dystocia on the lactation curve characteristics for milk yield and composition in Holstein cows, six non-linear models (Brody, Wood, Sikka, Nelder, Dijkstra and Rook) were fitted on 5,917,677 test day records for milk yield (MY), fat (FP) and protein (PP) percentages, fat to protein ratio (FPR) and somatic cell score (SCS) of 643,625 first lactation Holstein cows with normal calving or dystocia from 3146 herds which were collected by the Animal Breeding Center of Iran. The models were tested for goodness of fit using adjusted coefficient of determination, root means square error, Akaike’s information criterion and Bayesian information criterion. Rook model provided the best fit of the lactation curve for MY and SCS in normal and difficult calvers and dairy cows with dystocia for FP. Dijkstra model provided the best fit of the lactation curve for PP and FPR in normal and difficult calvers and dairy cows with normal calving for FP. Dairy cows with dystocia had generally lower 100-d, 200-d and 305-d cumulative milk yield compared with normal calvers. Time to the peak milk yield was observed later for difficult calvers (89 days in milk vs. 79 days in milk) with lower peak milk yield (31.45 kg vs. 31.88 kg) compared with normal calvers. Evaluation of the different non-linear models indicated that dystocia had important negative effects on milk yield and lactation curve characteristics in dairy cows and it should be reduced as much as possible in dairy herds.

Factors affecting milk production in Improved Awassi dairy ewes

2000 ◽  
Vol 71 (3) ◽  
pp. 607-615 ◽  
Author(s):  
E. Gootwine ◽  
G. E. Pollott
Keyword(s):  
Milk Production ◽  
Litter Size ◽  
Milk Yield ◽  
Intensive Management ◽  
Short Term ◽  
Artificial Rearing ◽  
Factors Affecting ◽  
Lactation Curve ◽  
Total Milk ◽  
Term Variation

AbstractThis study investigated the factors affecting milk production and lactation curve parameters from the complete lactations of Awassi dairy sheep. The animals were kept in a single flock under intensive management and milked twice daily starting at lambing. Lambs were removed from the ewes at birth into an artificial rearing unit. The results of the analyses of 3740 complete lactations showed a mean litter size of 1·28 lambs born per ewe lambing and average total milk yield of 506 l from lactations 214 days in length and with an average lambing interval of 330 days. Mean lactation number was 3·71 and ewes conceived on average in the 6th month of the lactation. The lactations peaked on day 45 at a yield of 3·44 l. The maximum milk secretion potential of the ewes was 3·9 l/day, with milk yield increasing at 62 g/day mid way between lambing and peak yield and declining at 16·5 g/day mid way between peak and the end of lactation. Age at first lambing, lactation number, litter size, month of lambing and month of conception during the lactation had significant effects (P < 0·05) on some or all of the lactation parameters investigated. Relatively high milk yield was obtained in lactations starting in the January to March period. The monthly effect on milk production was explained by significant (P < 0·05) heat load and photoperiod effects. High milk production was found to have a significant (P < 0·05) adverse effect on reproductive performance. Conception followed a significant (P < 0·05) short term variation in milk production.

scholarly journals Comparative Evaluation of Lactation Curves of Crossbred Dairy Cows in Field Conditions in Tamil Nadu, India 

2021 ◽  
Author(s):  
C. Balan ◽  
M. Thirunavukkarasu
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Tamil Nadu ◽  
Field Conditions ◽  
Crossbred Cows ◽  
Lactation Curve ◽  
Daily Milk Yield ◽  
Best Fit ◽  
Daily Milk

Background: Various mathematical models have been tried by different researchers to fit the lactation curves in indigenous, exotic and crossbred cows maintained in organised farms only. Hence, this study was aimed to fit various lactation models and to identify the best fit model (s) for prediction of milk production in crossbred dairy cows in field conditions.Methods: Multistage random sampling procedure was used for selection of 100 dairy cows for the purpose of data collection. The monthly milk yield data (up to 10 months of lactation) of the selected crossbred cows reared in field conditions of Tamil Nadu State, relating to the period from 2017-20, were collected for lactation curve modelling. The milk data so collected were used to fit 14 lactation curve models in the study. The highest Coefficient of Determination (R²) value and the least Root Mean Square Error (RMSE) value were used as the criteria to select the best fit model(s).Result: The overall average total milk production was estimated to be 2223.19 kg per lactation in 10 months of lactation in the selected crossbred cows. Average daily milk yield at the first month of lactation was 9.16 kg and the highest daily milk yield of 9.56 kg was observed at the second month of lactation. At the end of the lactation, the lowest yield was 5.01 kg per day and hence the overall average daily milk yield was found to be 7.41 kg. Based on the selection criteria, the Mitscherlich X Exponential model was identified as the best fit model, followed by Ali and Schaeffer and Morant and Gnanasakthy model for prediction of milk production in crossbred dairy cows reared in field conditions and the estimated lactation curve model parameters a, b, c and d values for the best fit model were 331.71, 1519.82, 9.56 and 0.07 kg, respectively. 

Effect of Herbal Galactogogue (Sanjivani biokseera) on Milk Yield and Milk Constituents in Lactating Kankrej Cattle at Organised Farm

2019 ◽  
Vol 15 (02) ◽  
pp. 39-41
Author(s):  
H H Panchasara ◽  
A B Chaudhari ◽  
D A Patel ◽  
Y M Gami ◽  
M P Patel
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Composition ◽  
Nutritional Requirements ◽  
Not Given ◽  
Distinct Effect ◽  
Lactating Dairy Cows ◽  
Group I ◽  
Effect Of Feeding

The study was conducted to evaluate the effect of feeding herbal galactogogue preparation (Sanjivani biokseera) on the milk yield and milk constituents in lactating Kankrej cows. Thirty-two lactating Kankrej cows in their 1st to 6th lactation were taken for the experiment from 3 days after calving up to 52 days postpartum. All the animals were fed as per the standard seasonally available roughages and concentrates to meet their nutritional requirements. The cows were randomly divided into two uniform groups of 16 cows in each according to initial milk yield and milk composition. The animals in group-I were not given any supplement and served as control. The animals in group-II were given Sanjivani biokseera (Naturewell Industries) @ 60 g per day for 1-month, commencing 3 days after calving, in addition to the usual feeds/fodders. A clear difference was observed in milk yield from day 8 onward of experiment between groups with significant (plessthan0 0.05) higher values from day 16-52 in cows fed herbal galactogogue as compared to control, but no such distinct effect on milk constituents was observed on day 52 when analyzed. The use of herbal galactogogue significantly (p lessthan 0.05) increased the overall average of 52 days milk production, which was 9.34 ± 0.21 lit/day in supplemented as compared to 7.75 ± 0.26 lit/day in control animals. It was concluded that herbal galactogogue (Sanjivani biokseera) could increase milk yield in lactating dairy cows through its galactopoetic property and improved rumen environment.

Effects of feeding peas to high-producing dairy cows

1995 ◽  
Vol 75 (4) ◽  
pp. 625-629 ◽  
Author(s):  
R. R. Corbett ◽  
L. A. Goonewardene ◽  
E. K. Okine
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Dairy Herd ◽  
Protein Source ◽  
Canola Meal ◽  
Stage Of Lactation ◽  
Nutrient Analyses ◽  
Protein Milk

The effect of substituting peas for soybean and canola meals as a protein source in a high-producing dairy herd was studied in 66 Holstein cows, divided into two groups based on stage of lactation, parity, level of milk production and days in milk. Two 18.5% crude protein grain concentrate diets were formulated based on the nutrient analyses of the forages available. The control grain mix contained standard protein sources, principally soybean and canola meal (SBM\CM) while the test grain mix was formulated to contain approximately 25% field peas as the major source of protein. Both grain rations were formulated to the same nutrient specifications and balanced for undegradable protein. The duration of the trial was 6 mo during which grain feeding levels were adjusted monthly based on milk yield. For cows in early lactation, 4% fat-corrected milk yield was higher (P < 0.05) for cows fed pea based concentrates (31.3 kg d−1) than for cows fed SBM\CM supplement (29.7 kg d−1). Fat-corrected milk yield was not affected by source of protein in mid- and late-lactation cows. Fat-corrected milk production was not different (P > 0.05) for cows fed SBM\CM compared with cows fed the pea supplement when cows across all stages of lactation were included in the analyses. Milk fat percent was significantly higher (P < 0.05) for early- and mid-lactation cows fed the pea supplement. The results suggest that peas can be substituted for SBM\CM as a protein source for high-producing dairy cows. Key words: Dairy cow, pea, soybean and canola meal supplement, undegradable protein, milk production

scholarly journals Milkability evaluation of Holstein dairy cows by Lactocorder

2011 ◽  
Vol 28 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Peter Strapák ◽  
Peter Antalík ◽  
Iveta Szencziová
Keyword(s):  
Dairy Cows ◽  
Milk Yield ◽  
Flow Rate ◽  
Flow Characteristics ◽  
Detailed Comparison ◽  
Milk Flow ◽  
Lactation Stage ◽  
Total Milk ◽  
Positive Correlations ◽  
Holstein Dairy Cows

Milkability evaluation of Holstein dairy cows by LactocorderThe aim of this work was to evaluate chosen milk flow characteristics of Holstein dairy cows, using mobile electronic milk flow meters - Lactocorders. A total of 181 Holstein dairy cows were evaluated and divided according to parity, lactation stage and bimodality in order to carry out a detailed comparison of measured milkability traits. The average total milk yield was 11.98±3.41 kg per milking with an average milk flow rate of 2.52±0.75 kg min-1 and a maximum milk flow rate of 3.94±1.30 kg min-1. The total milk yield showed positive correlations with the average milk flow rate (r = 0.48; P<0.001) and also with the maximum milk flow rate (r = 0.32; P<0.001). More than 47% of milk flow curves were classified as bimodal. Bimodality was positively correlated with the duration of the incline phase (r = 0.73; P<0.001) and negatively correlated with the quantity of milk obtained during the first minute of milking (r = -0.34; P<0.001). In relation to the lactation stage - the highest average milk flow rate was reached by Holstein dairy cows at the beginning of the lactation (up to 100 days in milk), and in relation to parity - the highest milk flow rates were measured in second-lactation dairy cows.

scholarly journals Association of Feed Efficiency, Feeding Rate, and Behaviour with the Milk Performance of Dairy Cows

Dairy ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 684-694
Author(s):  
Lenka Krpálková ◽  
Niall O’Mahony ◽  
Anderson Carvalho ◽  
Sean Campbell ◽  
Gerard Corkery ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Feeding Behaviour ◽  
Feeding Rate ◽  
Feeding Time ◽  
Feed Conversion ◽  
Milk Performance

Identification of the associations of cow feed efficiency with feeding behaviour and milk production is important for supporting recommendations of strategies that optimise milk yield. The objective of this study was to identify associations between measures of feed efficiency, feed intake, feeding rate, rumination time, feeding time, and milk production using data collected from 26 dairy cows during a 3 month period in 2018. Cows averaged (mean ± standard deviation) 2.2 ± 1.7 lactations, 128 ± 40 days in milk, 27.5 ± 5.5 kg/day milk, 1.95 ± 0.69 kg feed/1 kg milk—the measure used to express feed conversion ratio (FCR), 575 ± 72 min/day rumination time, and 264 ± 67 min/day feeding time during the observation period. The coefficient of variation for rumination time (min/d) was 12.5%. A mixed linear model was selected for analyses. The most feed inefficient cows with the highest FCR (≥2.6 kg feed/1 kg milk) showed the lowest milk yield (24.8 kg/day), highest feed intake (78.8 kg), highest feeding rate (0.26 kg/min) and BCS (3.35 point). However, the relative milk yield (milk yield per 100 kg of body weight) was the highest (4.01 kg/day) in the most efficient group with the lowest FCR (≤1.4 kg feed/1 kg milk). Our study showed that the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk) had the highest rumination time (597 min/day; p < 0.05), feeding time (298 min/day; p < 0.05), rumination/activity ratio (4.39; p < 0.05) and rumination/feeding ratio (2.04; p < 0.05). Less active cows (activity time 164 min/day; p < 0.05) were the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk). The behavioural differences observed in this study provide new insight into the association of feed behaviour and feed efficiency with milk performance. Incorporating feeding behaviour into the dry matter intake model can improve its accuracy in the future and benefit breeding programmes.

scholarly journals On designing the average lactation curve at the ascending phase

1962 ◽  
Vol 34 (1) ◽  
pp. 162-168
Author(s):  
Aarne Mäkelä
Keyword(s):  
Dairy Cows ◽  
Milk Yield ◽  
Lactation Period ◽  
Lactation Curve ◽  
The Mean ◽  
The Individual ◽  
Daily Milk Yield ◽  
Daily Milk

Comparisons are made between different methods to find the peak production (maximum daily milk yield) and methods to design the average lactation curve at the ascending phase in dairy cows. It was noted that in order to determine the height and location of the maximal producing capacity of a cow in a known lactation period, it is preferable to choose the peak production as a mean of three subsequent best days. It was also noted that the usual methods for drawing the average lactation curves do not give a true picture of the height and location of the peak. The author suggests a method for determining the average lactation curve at the ascending phase by using the averages of both milk productions and times involved in reaching the peak and known fractions (e.g. 1/8, 1/4, 1/2, 3/4, and 5/4) of it. In this lactation curve the peak production is the mean of the peaks of individual cows, and the time involved in reaching it is the mean of the durations of the ascending phases of the individual cows.

Effect of temperature and relative humidity on the milk production of dairy cows

2021 ◽  
Vol 13 (2) ◽  
pp. 22-27
Author(s):  
Ivan Imrich ◽  
Róbert Toman ◽  
Martina Pšenková ◽  
Eva Mlyneková ◽  
Tomáš Kanka ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Effect Of Temperature ◽  
Winter Period ◽  
Summer Period ◽  
Average Temperature ◽  
Holstein Friesian ◽  
Humidity Index ◽  
Index Value

The aim of this study was to evaluate the influence of environmental housing conditions on the milk yield of dairy cows. Measurements were taken in the summer period from June to September 2020 and in the winter period during January 2021 on a large-capacity farm of Holstein Friesian cattle. Cows were housed in free stall barn with the lying boxes and selected during the second or third lactations, in the summer period from the 51st day to the 135th day and in the winter period from the 64th day to the 120th day of lactation. The average temperature in the housing was 23 °C in summer, and 7.05 °C in winter. The average THI (thermal humidity index) value in summer was 70.43, but during the day the THI values sometimes reached 75. The dairy cows were therefore exposed to heat stress during summer. Increasing THI and temperature values negatively affected the milk yield, as there was a negative correlation between both THI and milk yield (r = -0.641; p <0.01) and temperature and milk yield (r = -0.637; p <0.01). Milk production in winter was at 58.77 kg per day and in summer at 49.55 kg per day. In the summer, the milk had a significantly lower content of fat (p <0.05), proteins (p <0.001), lactose (p <0.001), minerals (p <0.001) and conversely, a higher number of somatic cells (p <0.01). These results show that worse environmental conditions during the summer negatively affected the level of milk yield and the composition of the cows’ milk.

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