scholarly journals Genetic profile of Holstein and Jersey dairy bull lines available in Brazil

2014 ◽  
Vol 15 (1) ◽  
pp. 261-269
Author(s):  
Leila de Genova Gaya ◽  
Diego de Córdova Cucco ◽  
Leandro Homrich Lorentz ◽  
Marcio Pereira Soares ◽  
Fernanda Batistel ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Linear Models ◽  
Genetic Profile ◽  
Holstein Breed ◽  
Genetic Pattern ◽  
Holstein Bulls ◽  
Genetic Profiles ◽  
Dairy Bull ◽  
Milk Solids

The Holstein and Jersey dairy cattle breeds are among the most prevalent in Brazil. To evaluate differences among the PTAs (predicted transmitting abilities) of these breeds and their lines, data were collected on 385 Holstein bulls and 82 Jersey sires with semen commercially available from nine Brazilian companies. Three different sire lines for each breed were found. The general linear models method was used for the comparison among lines and between breeds. The two most prevalent lines of Holstein breed presented higher average PTAs for milk yield (1,061.04 pounds and 975.32 pounds) and lower PTAs for percentage of milk solids (from -0.05% to -0.0003%) (P<0.05). These results indicate the supply of sires that mostly increase the milk yield in the Brazilian market. The Jersey breed presented a higher inbreeding coefficient (6.62%) than the Holstein breed (5.14%) (P<0.05). Although the Holstein breed presented higher PTAs for milk yield and lower PTAs for percentage of milk solids (P<0.05), the productive life of the Jersey breed (1.17 months) was longer than it was in the Holstein breed (0.40 months) (P<0.05). We identified the existence of an important variability of the available genetic profiles, what allows the Brazilian producers to choose the most adequate semen for their production system. It is necessary to consider the genetic profiles of sires' lines offered for artificial insemination in Brazil to understand and direct the genetic pattern of Brazilian dairy cattle.

scholarly journals Associations between milking technology, herd size and milk production parameters on commercial dairy cattle farms

2020 ◽  
Vol 70 (2) ◽  
pp. 103-111
Author(s):  
Dorottya Ivanyos ◽  
László Ózsvári ◽  
István Fodor ◽  
Csaba Németh ◽  
Attila Monostori
Keyword(s):  
Dairy Cattle ◽  
Milk Production ◽  
Milk Yield ◽  
Linear Models ◽  
Herd Size ◽  
Exact Test ◽  
Production Parameters ◽  
Daily Milk Yield ◽  
Cattle Farms ◽  
Daily Milk

The aim of the study was to survey the milking technology and to analyse the associations between milking parlour type, herd size, and milk production parameters on dairy cattle farms. The milking technology was surveyed by using a questionnaire in 417 Hungarian dairy herds with 177,514 cows in 2017, and it was compared with their official farm milk production data. The surveyed farms were categorized according to their size (1-50, 51-300, 301-600, and &gt;600 cows) and to their milking parlour types (herringbone, parallel, carousel, and others). The relationships were analysed by multivariate linear models, one-way ANOVA, and Fisher’s exact test. Pairwise comparisons were performed by Tukey’s post hoc tests. The prevailing type of milking parlour was herringbone (71.0 %), but on larger farms the occurrence of parallel and carousel parlours increased (p&lt;0.001). The number of milking stalls per farm increased with herd size (p&lt;0.001). Farms with herringbone parlour had significantly smaller number of milking stalls than that of parallel (p=0.022) and carousel (p&lt;0.001) parlours, and the cows were mostly milked two times, while in carousel milking parlours mostly three times a day. As the herd size increased, so did daily milk yield (p&lt;0.001) and daily milk production per cow (p&lt;0.001). Herd size was associated with somatic cell count (p&lt;0.001). The type of milking parlour showed significant association with daily milk yield (p=0.039) and dairy units with herringbone milking system had the lowest milk quality. Our findings show that herd size has greater impact on milk production parameters than milking technologies.

Behavioural manifestations of dairy cattle in the pasture-based system

2012 ◽  
Vol 29 (2) ◽  
pp. 71-80
Author(s):  
Jarmila Voříšková ◽  
Karel Beneš ◽  
Milan Kobes ◽  
Jan Pozdíšek
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
The Other ◽  
Dairy Herds ◽  
Mountainous Area ◽  
Slight Variation ◽  
Grazing Season ◽  
Holstein Breed ◽  
Time Period ◽  
Grazing Period

Abstract A pasture-based system for dairy cattle is not common due to the need for milking, despite the fact that this system provides the possibility of natural animal behaviour. Six behavioural observations were carried out during the grazing season in dairy herds bred in a mountainous area (700 m a. s. l.) The basic herd was comprised of 53 cows, mainly of the Holstein breed. From April to November the herd was located on pastures near the stables and milked twice a day in a tandem milking parlour. Feed ration was composed of pasture and concentrated feed in the stable. During the grazing season, there was a slight variation with a tendency to extend the grazing period to the autumn months. The cattle grazed the shortest time in May - 35.0% of the day or 8.4 hours. In the autumn months the grazing time increased by 2.2 and 2.6 hours respectively. Cows were resting the longest time period in May and June (8.9 and 9.1 h respectively). On the other hand, cows were resting for the shortest time in October (6.8 hours). During the grazing period the milk yield decreased from 20.4 kg in April to 14.4 kg in November.

scholarly journals ESTIMATION OF HOLSTEIN BREED BULLS BY DAIRY PRODUCTIVITY OF THEIR DAUGHTERS

2020 ◽  
Vol 59 ◽  
pp. 26-34
Author(s):  
S. L. Voitenko ◽  
O. V. Sydorenko
Keyword(s):  
Milk Yield ◽  
Phenotypic Variability ◽  
Milk Productivity ◽  
Paternal Origin ◽  
Black And White ◽  
Holstein Breed ◽  
The Third ◽  
Holstein Bulls ◽  
The Difference ◽  
Dairy Breed

The scientific community has shown that the genetic improvement of dairy cattle depends on many genotypic factors, including paternal ancestry and lineage. With this in mind, the purpose of our research was to evaluate the Holstein bulls of black-and-white and red-and-white suits of different lines for the milk productivity of their daughters. The research was carried out on the basis of primary breeding records of 10 breeding herds of Ukrainian Black-and-White Dairy breed, 3 – Ukrainian Red-and-White Dairy breed and one – Ukrainian Red Dairy breed, which are subordinated to NAAS. Cows of the studied breeds has divided into groups according to lineage and paternal origin. Studies have revealed a significant differentiation of milk yield of cows of the first and highest lactation not only of one breed, but also of linear affiliation and paternal origin. It was found that the yield of the first lactation in cows of the Ukrainian Black-and-White Dairy breed varied from 3211 kg (Damir 7100354042) to 7884 kg (Dzhokus 113080315) of milk. Noteworthy are the daughters of Dzhokus 113080315, from which 9143 kg of milk were obtained for higher lactation, Polyarsten 342347941 and Manteno 344222859 – 8248 kg and 8290 kg of milk, respectively. The significant influence of paternal origin on the yield of Ukrainian Black-and-White Dairy breed cows of the first and higher lactation (31.0%; P > 0.999) and 37.3% has been proved; P > 0.999). The influence of genealogical formation on the milk productivity of cows was significant and amounted to 10.8% for the first lactation, higher – 10.2%. Some of the first-born Ukrainian Black-and-White Dairy breed has characterized by high milk productivity, which steadily increased until the third and higher lactation. The yield of cows of the Ukrainian Red-and-White Dairy breed of the first lactation varied from 5414 kg (Dialog 2009) to 6689 kg (Larets 6177), testifying to better homogeneity of herds in terms of milk productivity compared to the Ukrainian Black-and-White dairy breed. The highest yield of the third and highest lactation – 7626 kg, had cows-daughters of the bull Roman 660886883 Starbuck line 352790. The variability of milking cows of Ukrainian Red-and-White Dairy breed of the first and highest lactation by 25.0% and 15.2%, respectively, was due to the influence of the father offspring and to a lesser extent – belonging to the line. A very high (6517–8013 kg) realization potential of milking cows of the Ukrainian Red Dairy breed was established, but it also depended on the paternal origin and linear affiliation. The highest yield of the first lactation were shown by the daughters of the bull Belisar 365235897, Dzhorin 114414759 and Tumpi 112367468, who produced 8013 kg, 7323 kg and 7170 kg of milk, respectively. In cows of this breed it was found that yield increased with increasing serial number of lactation, with the third and higher lactation cows produced more than 8000 kg of milk per lactation, and the daughters of bull Dzhorin 114414759 – more than 9000 kg. The influence of the bull on the milk productivity of the first-born cows of the Ukrainian Red Dairy breed (16.7%; P > 0.999) is almost three times higher than this linear affiliation. Significant phenotypic variability of milk productivity of cows of different breeds of half-sisters by the father is established. The advantage of the daughters of the bull Belisar 365235897 of the Ukrainian Red Dairy breed on milking of the first lactation over the representatives of the Ukrainian Red-and-White Dairy breed was 1932 kg (p < 0.001). The difference in milk yield of the first lactation of the half-sisters by the father, the bull Konbeo 579810507 was 1007 kg (p < 0.01), and Roman 660886883 – 717 kg. Thus, a significant phenotypic variability of milk productivity of cows of different breeds of half-sisters by father was established. At the same time, regardless of the breeder, the cows of the Ukrainian Red Dairy breed were characterized by higher milk yield of the first lactation in comparison with the Ukrainian Red-and-White Dairy breed.

EVALUATION OF THE HOLSTEIN BREED SIRES BY THE QUALITY OF OFFSPRING

2020 ◽  
Author(s):  
E.И. САКСА
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Country Of Origin ◽  
Negative Evaluation ◽  
Breeding Value ◽  
Breeding Method ◽  
Individual Values ◽  
Black And White ◽  
Holstein Breed ◽  
Holstein Bulls

Приведены результаты использования быков голштинской породы, оцененных по качеству потомства, в хозяйствах Российской Федерации, в зависимости от происхождения, метода разведения и уровня их племенной ценности в стране происхождения. Анализ материалов оценки голштинских быков по качеству потомства показал, что из 1995 быков 40,9% являются улучшателями удоя (+183 кг молока, +7,2 кг молочного жира), 52,7% — нейтральными (-86 кг молока, -3,3 кг молочного жира) и только 0,3% — ухудшателями (-407 кг молока, -15,2 кг молочного жира). Высокая доля нейтральных быков (52,7%) и отрицательная оценка их племенной ценности по удою — результат действующей «инструкции», согласно которой производителям при оценке до -1404 кг молока по сравнению со сверстницами присваивают категорию «нейтральный». Выявлены племенные качества голштинских быков в зависимости от метода разведения. Высокую племенную ценность по удою (+439 кг молока) имеют голштинские быки, оцененные по качеству потомства на маточном поголовье скота ярославской породы. Племенная ценность быков, оцененных на маточном поголовье холмогорского скота, составила +153 кг, на поголовье черно-пестрого — +23 кг молока; при чистопородном разведении — +5 кг молока. Результаты использования импортной спермы 196 быков различного происхождения на поголовье 17087 дочерей-первотелок (8665 кг молока, 3,89% жира, 3,23% белка) свидетельствуют, что одни и те же быки имели наиболее высокую племенную ценность по удою при скрещивании с черно-пестрыми коровами (от +100 кг до 272 кг молока) по сравнению с чистопородным разведением (от +14 кг до -81 кг молока). Вышеуказанная закономерность сохраняется при оценке голштинских быков различного происхождения с уровнем племенной ценности до +601 кг молока в стране происхождения. Только выдающиеся по своим племенным качествам производители (+601 кг молока и более в стране происхождения), оцененные в отечественных стадах, имели высокую племенную ценность как при чистопородном разведении (+490 кг молока), так и при скрещивании (+539 кг молока) при продуктивности дочерей свыше 9000 кг молока. Выделены быки с высокими индивидуальными значениями племенной ценности. Для совершенствования продуктивных качеств скота голштинской породы необходимо использовать в воспроизводстве быков с оценкой племенной ценности по удою методом «дочери—сверстницы» не менее +200 кг молока. Требования к уровню племенной ценности быков увеличиваются с ростом продуктивности стад. The results of the use of Holstein breed bulls, evaluated by the merit of the offspring, in the farms of the Russian Federation, depending on the origin, breeding method and the level of their breeding value in the country of origin, are presented. Analysis of data for evaluating Holstein bulls by the merit of their offspring showed that out of 1995 bulls 40.9% are milk yield improvers (+183 kg of milk, +7.2 kg of milk fat), 52.7% are neutral (-86 kg of milk, -3, 3 kg of milk fat) and only 0.3% — deteriorating (-407 kg of milk, -15.2 kg of milk fat). The high proportion of neutral bulls (52.7%) and a negative evaluation of their breeding value for milk yield is the result of the current “instruction”, according to which sires, when evaluating up to -1404 kg of milk compared to their herd-mates, are assigned the category “neutral”. The breeding merits of Holstein bulls were revealed depending on the breeding method. Holstein bulls have a high breeding value for milk yield (+439 kg of milk), evaluated by their offspring merit when using Yaroslavl cattle mothers. The breeding value of bulls evaluated on the Kholmogory breeding mothers was +153 kg, on the Black and White stock - +23 kg of milk; with purebred breeding — +5 kg of milk. The results of using imported semen from 196 sires of various origins in a herd of 17087 first-calf daughters (8665 kg of milk, 3.89% fat, 3.23% protein) indicate that the same bulls had the highest breeding value for milk yield when mated with Black and White cows (+100 kg to +272 kg of milk) in comparison with purebred breeding (+14 kg to -81 kg of milk). The above mentioned rule holds true when evaluating Holstein bulls of various origins with a breeding value of up to +601 kg of milk in the country of origin. Only top sires with outstanding breeding merit (+601 kg of milk and more in the country of origin), evaluated in domestic herds, had a high breeding value both in pure-bred stocks (+490 kg of milk) and when crossing (+539 kg of milk) with the productivity of daughters over 9000 kg of milk. Bulls with high individual values of breeding merit have been identified. In order to improve the productive qualities of Holstein cattle, it is necessary to use bulls with the evaluation of the milk yield breeding merit of at least 200 kg of milk by the "daughter-herd mates" method. The requirements for the level of breeding value of bulls increase with the increase of the herd productive ability.

EFFECT OF SELECTION FOR MILK AND TOTAL MILK SOLIDS ON BUTTERFAT, SOLIDS-NOT-FAT, AND PROTEIN IN MILK FROM DAIRY CATTLE

1964 ◽  
Vol 44 (3) ◽  
pp. 290-296 ◽  
Author(s):  
R. J. Curtis ◽  
C. G. Hickman
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Downward Trend ◽  
Production Data ◽  
Breeding Values ◽  
Total Milk ◽  
Progeny Tests ◽  
Selection For ◽  
Milk Solids ◽  
Total Digestible Nutrient

Production data from five Holstein, six Ayrshire, and three Jersey herds were analysed to give the expected effects of milk and total milk solids selection on milk quality as measured by per cent butterfat, solids-not-fat, and protein. Progeny tests were conducted at 11 locations under total digestible nutrient controlled, year-round stable feeding conditions.With varying breeding values for total milk solids yield, there was no definite trend between quality and quantity for Holsteins and Ayrshires, but in Jerseys quality showed a definite downward trend with increasing quantity.For milk yield breeding values the same applied except that protein percentage in Holsteins also showed a downward trend with increasing quantity.

scholarly journals Результати використання бугаїв-плідників голштинської породи при створенні високопродуктивного стада

2019 ◽  
pp. 169-180
Author(s):  
Т. В. Підпала ◽  
Є. М. Зайцев ◽  
А. О. Правда
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Milk Fat ◽  
Milk Composition ◽  
Reproductive Capacity ◽  
Practical Significance ◽  
Positive Correlation ◽  
Holstein Breed ◽  
Service Period ◽  
High Level

Мета статті – оцінити прояв господарсько корисних ознак у корів-дочок різних бугаїв-плідників голштинської породи. Методика дослідження. У процесі дослідження використані загальноприйняті зоотехнічні методи (індивідуальний облік молочної продуктивності, відтворювальної здатності), лабораторні (визначення якісного складу молока), ретроспективний аналіз (показники за весь період використання тварин), варіаційно-статистичний метод (визначення параметрів ознак). Результати дослідження. У результаті вивчення використання бугаїв-плідників голштинської породи при створенні високопродуктивного стада молочної худоби з’ясовано, що на рівень розвитку продуктивних, відтворювальних і адаптивних властивостей корів-дочок впливає походження за батьком. Встановлено взаємозв’язок між господарсько корисними ознаками корів первісток голштинської породи німецької та української селекції, які походять від різних бугаїв. Незалежно від походження піддослідних тварин зберігається позитивна високого ступеня кореляція між надоєм і кількістю молочного жиру та білка. Загальною закономірністю для потомства бугаїв голштинської породи є наявність позитивної кореляції низького, середнього і високого ступенів між надоєм і тривалістю сервіс-періоду. Визначено відмінності за напрямом і ступенем кореляційної залежності між продуктивними і відтворювальними ознаками у корів-первісток, які й характеризують різноманітність впливу бугаїв на їхніх дочок. Елементи наукової новизни. Набули подальшого розвитку теоретичні та практичні положення щодо підвищення продуктивності тварин та створення високопродуктивних стад молочної худоби за використання генофонду голштинської породи. Практична значущість. Одержані результати потрібно враховувати у процесі поліпшуючої селекції під час формування високопродуктивного стада молочної худоби голштинської породи. The purpose of the article is to evaluate the manifestation of economically useful signs of cow-daughters of Holstein breed different servicing bulls. Methods of the research. In the course of the study, commonly used zoo-technical methods (individual accounting of milk productivity, reproductive capacity), laboratory (determining the qualitative milk composition), retrospective analysis (indicators for the entire period of using animals), variation-statistical method (determining sign parameters) were used. The research results. As a result of using bulls for service of Holstein breed in creating a highly productive herd of dairy cattle it has been established that the level of developing productive, reproductive and adaptive properties of cow-daughters is influenced by the origin of the father-parent.  The correlation has been established between economically useful signs of cows-firstlings of the Holstein breed of German and Ukrainian selection from various bulls. Regardless of the experimental animals’ origin, there is a high-level positive correlation between the milk yield and the amount of milk fat and protein. The common peculiarity for the offspring of the Holstein breed is the presence of a positive correlation of the low, middle and high levels between the milk yield and the duration of the service period. The differences as to the direction and the degree of correlation dependence between productive and reproductive features of cows-firstlings have been determined, which characterize the diversity of bulls’ influence on their daughters. The elements of scientific novelty. The theoretical and practical propositions for raising the productivity of animals and creating highly productive herds of dairy cattle by using the gene pool of Holstein breed have been further developed. Practical significance. The obtained results should be taken into account in the process of improving the selection during the formation of a highly productive herd of the Holstein breed dairy cattle.

Grazing behaviour of dairy cattle selected for high and average milk yield

1999 ◽  
Vol 24 ◽  
pp. 197-202
Author(s):  
B. Fuerst-Waltl ◽  
J. Sölkner ◽  
M. C. Appleby
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Dairy Herd ◽  
Late Pregnancy ◽  
Control Line ◽  
Night Time ◽  
Lactating Cows ◽  
Sampling Procedures ◽  
Milk Solids ◽  
Grazing Behaviour

AbstractThe present study was designed to examine the effects of selection for milk production as well as stage of pregnancy, on the grazing behaviour of dairy cattle. Subjects were 43 Holstein-Friesian cows from the Langhill Dairy Herd in Edinburgh. The herd consists of two genetic lines, one selected for high milk solids yield and a control line of average genetic index for milk solids yield. Animals of both genetic lines were observed as non-lactating heifers in 1992 and as first lactating and dry cows in 1993. Behaviour was recorded using scan-sampling procedures during seven observation periods at day and two periods at night. For analysis animals were grouped by their first lactation 305-day ECM (energy-corrected milk) yield for four observation periods during the day and for both night time observations animals were additionally grouped by stage of pregnancy. The majority of selected animals was in the high yielders’ group. In September 1992 and 1993 herbage intake on pasture was also investigated.No significant influence of 305-day ECM yield on time spent grazing, lying or ruminating was found. The influence of stage of pregnancy was stronger, although results for heifers and cows were contradictory. During the day heifers which were closer to parturition spent less time grazing (P < 0.10 in two of three periods) and more time lying (P < 0.05 in one period) whereas lactating cows in late pregnancy spent more time grazing and less time lying (P < 0.01 and P < 0.10, respectively). High yielders had higher herbage intakes than low yielders but this result was significant for heifers only (P < 0.01).

scholarly journals Interaction of economically useful traits in cows of different breeds

2021 ◽  
Vol 282 ◽  
pp. 03010
Author(s):  
M.B. Rebezov ◽  
А.S. Gorelik ◽  
Y.S. Pavlova ◽  
E.V. Khorobrykh ◽  
P.V. Sharavyev
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Correlation Coefficients ◽  
Comparative Assessment ◽  
Holstein Cows ◽  
Positive Correlation ◽  
Quantitative Indicator ◽  
Holstein Breed ◽  
Machine Milking ◽  
Service Period

A related Holstein breed has recently been used to improve domestic dairy cattle and create highly productive herds by purchasing semen from breeding bulls, as well as a large number of heifers and calves of foreign breeding. The purpose of the work is a comparative assessment of the productive qualities of Black Pied and Holstein cows of foreign breeding. Purebred Holstein cows differ from animals of Black Pied breed in milk yield per lactation. Cows of both breeds have fairly high suitability for machine milking. The priority remains with the animals of the Holstein breed of foreign selection. In terms of milking intensity and udder volume, they reliably surpass Black Pied cows at P≤0.05 - P≤0.01, respectively, in terms of indicators. Holstein cows were also the best in the udder index. Correlation coefficients between the productive qualities, as well as between the quantitative indicator of productivity and the qualitative indicators of the suitability of cows for machine milking, were the same or did not differ significantly. A positive correlation was established between milk yield and the duration of the service period from 0.1 to 0.05, depending on the breed.

scholarly journals INTRA-LINEAR SELECTION AND CROSS-LINE SELECTION WHEN CREATING HIGHLY PRODUCTIVE DAIRY CATTLE HERDS

2021 ◽  
Vol 246 (2) ◽  
pp. 94-98
Author(s):  
N.L. Ignatieva ◽  
◽  
I.V. Voronova ◽  
E.Yu. Nemtseva ◽  
◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Selection Methods ◽  
Cattle Breeding ◽  
Holstein Breed ◽  
Linear Selection ◽  
Dairy Cattle Breeding ◽  
Line Selection ◽  
The Cross ◽  
Cattle Herds

The aim of the research was to evaluate the compatibility of lines and improve on this basis the traditional selection methods for creating breeding herds in dairy cattle breeding. The results of the analysis showed that the best milk yield among the other lines were the first-born heifers (n=39) of the Holstein line Vis Back Idial (6441 kg of milk). The analysis of the results of the intra-linear selection showed that the best milk yield was also distinguished by the first-born heifers of the Vis Back Idial line – 6721 kg of milk. Analyzing the cross-line of the Vis Back Idial with other lines of the Holstein breed (MCH, RS, and PG), it should be noted that they are superior to their first-calf peers by 253-530 kg of milk. The first-calf cows, derived from the cross of the Montwick Miftaine line and the Reflection Sovering and Pabst Governer lines, also have some superiority over their peers. Thus, when improving breeding herds of dairy cattle, it is necessary to use both intra-linear selection and cross-lines, taking into account their compatibility.

Characterization of Lactation Curve Patterns using Non-linear Models in Crossbred Dairy Cattle

2021 ◽  
Author(s):  
Tassew Mohammed Ali ◽  
Raman Narang ◽  
P.P. Dubey ◽  
Simarjeet Kaur
Keyword(s):  
Dairy Cattle ◽  
Milk Yield ◽  
Linear Models ◽  
Biological Efficiency ◽  
Lactation Curve ◽  
Non Linear ◽  
Crossbred Dairy Cattle ◽  
Daily Milk Yield ◽  
Curve Patterns ◽  
Daily Milk

Background: Lactation curve patterns are currently integrated in dairy cow’s management software. Lactation curve modeling is useful for monitoring individual yields for diet planning, determining optimum strategies for insemination and genetic evaluation. It also helps for predicting expected missing values on field records and gives concise summary of biological efficiency and persistency of dairy cows.Methods: The study was aimed to characterize the lactation curve pattern for crossbred dairy cattle using different non-linear models. During the period 1991 to 2018, daily milk yield (DMY) consisted of 281698 records of 750 crossbred dairy cows maintained at Livestock Farms. GADVASU, Ludhiana, were collected for the study. Different non-linear models viz. exponential decline function (EDF), parabolic exponential model (PEM), inverse polynomial model (IPM), gamma-type function (GTF), mixed log function (MLF) and Ali and Schaeffer model (ASF) were used for the analysis. The model(s) that best fit and describe the curve characteristics was selected on the basis of coefficient of determination (R2), coefficient of variation (CV), Akaike information criterion (AIC) and mean square error (MSE).Result: The study clearly revealed that the PRM gave highest fit to DMY data with R2, MSE, AIC and CV values of 98.10%, 0.087, -743.31 and 2.37%, respectively. The IPM had also best fitted the observed DMY data with highest R2 (98.05%), lower MSE (0.089), low AIC (-735.8972) and lower CV (2.40%) values. The fitting of observed DMY data with predicted DMY were also found to be higher in the MLF (R2= 96.46%, MSE= 0.159, AIC= -558.16 and CV= 3.21%) and GTF (R2= 95.85%, MSE= 0.190, AIC= -505.24 and CV= 3.50%), whilst the EDF and PEM Models depicted relatively low fit to the DMY data when compared with the other non-linear models. However, IPM and GTF models can be used for accurate prediction of daily milk yield in the crossbred cattle population because they were typical standard lactation curves.

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