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Correlation of Breeding Values Among Test Day Record at First, Second, and Third Lactations on Milk Production of Dairy Cattle  [cached]
Karnaen Karnaen,J Arifin
Journal of Animal Production , 2009,
Abstract: The research was conducted at Balai Besar Pembibitan Ternak Unggul Sapi Perah (BBPTU-SP) Baturraden, Purwokerto, Central Java. The aims of this research were to study: (1) Breeding Value among test day record at first, second and third lactations on milk productions of dairy cattle, (2) Correlation of breeding values among test day record at first, second, and third lactations on milk production of dairy cattle. There were 4964 records of milk productions for 9 years since 1997 to 2006 dividing on 2299, 1668, and 997 records at first, second and third lactations, respectively. The observed individuals recorded from 45 bulls and 640 known cows. Fixed Effects were analyzed using General Linier Model. Variance components were predicted using Restricted Maximum Likelihood (REML). Breeding value was predicted with Best Linier Unbiased Prediction (BLUP). Heritability was 0.198 at first lactation, 0,270 at second lactation, 0.006 at third lactation, and 0,115 at 1st, 2nd, and 3rd lactations. Breeding Value (BV) between 2.57 and -1,68 at whole lactation. Bull has a highest breeding value on 58-18-N number of whole lactation. Three cows have highest breeding values on number of 914 - 98 (BV = 2,57), 817 - 97 (BV = 1,93), and 882 - 97 (BV = 1,67). Based on Spearman correlation, second lactation was appropriate for selection, because had the highest correlation with whole lactation at 0,67 for whole animal and 0,71 for bull. (Animal Production 11(2): 135-142 (2009) Key Words: dairy cattle, breeding value, milk production, test day, lactation
Estimation of economic values in three breeding perspectives for longevity and milk production traits in Holstein dairy cattle in Iran
Ali Ali Sadeghi-Sefidmazgi,Mohammad Moradi-Shahrbabak,Ardeshir Nejati-Javaremi,Abdolahad Shadparvar
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2009.359
Abstract: The objectives of this study were to estimate economic values (EVs) for three production traits (milk, fat and protein yields) and longevity and to develop a national selection index. The proposed Iranian selection index was compared with selection indices of three other countries in the world. A simple and appropriate model was used to describe the Holstein dairy cattle industry under an Iranian production system. Production parameters and economic data were collected from two Holstein dairy farms in Tehran province. The EVs were estimated at farm level for three breeding perspectives (maximized profit, minimized costs, and economic efficiency) and two restrictions in production system (fixed herd size and fixed total input). The average absolute EVs on profit perspective and herd size restriction for milk, fat, and protein yields (based on $/kg) and longevity ($/month) were 0.11, 0.89, -0.20, and 6.20, respectively. The average absolute EVs under minimized costs per unit of product interest for milk, fat, protein yields and longevity were -0.30, -3.43, 0.88 and -20.40, respectively. The average absolute EVs under maximized economic efficiency for milk, fat and protein yields and longevity were 0.34, 2.73, -0.99 and 36.33, respectively. Relative emphasis for three production traits and longevity were 59.7, 14.3, -3.0 and 23.1, respectively. The comparison of the proposed Iranian index with those countries where most of the semen and embryos are imported points out that developing a national selection index to improve cow profitability and optimum generic trends is necessary. Sensitivity analysis indicated that the influence of milk payment changes on EVs was the greatest as its influence on fat and protein EVs is substantial. EVs for milk and fat yields, with respect to price changes (milk, feed and non-feed), were the least sensitive and most sensitive, respectively.
Prediction of Breeding Values for Dairy Cattle Using Artificial Neural Networks and Neuro-Fuzzy Systems  [PDF]
Saleh Shahinfar,Hassan Mehrabani-Yeganeh,Caro Lucas,Ahmad Kalhor,Majid Kazemian,Kent A. Weigel
Computational and Mathematical Methods in Medicine , 2012, DOI: 10.1155/2012/127130
Abstract: Developing machine learning and soft computing techniques has provided many opportunities for researchers to establish new analytical methods in different areas of science. The objective of this study is to investigate the potential of two types of intelligent learning methods, artificial neural networks and neuro-fuzzy systems, in order to estimate breeding values (EBV) of Iranian dairy cattle. Initially, the breeding values of lactating Holstein cows for milk and fat yield were estimated using conventional best linear unbiased prediction (BLUP) with an animal model. Once that was established, a multilayer perceptron was used to build ANN to predict breeding values from the performance data of selection candidates. Subsequently, fuzzy logic was used to form an NFS, a hybrid intelligent system that was implemented via a local linear model tree algorithm. For milk yield the correlations between EBV and EBV predicted by the ANN and NFS were 0.92 and 0.93, respectively. Corresponding correlations for fat yield were 0.93 and 0.93, respectively. Correlations between multitrait predictions of EBVs for milk and fat yield when predicted simultaneously by ANN were 0.93 and 0.93, respectively, whereas corresponding correlations with reference EBV for multitrait NFS were 0.94 and 0.95, respectively, for milk and fat production. 1. Introduction Machine learning techniques, such as decision trees and artificial neural networks (ANN), are used increasingly in agriculture, because they are quick, powerful, and flexible tools for classification and prediction applications, particularly those involving nonlinear systems [1]. These techniques have been used for detection of mastitis [2], detection of estrus [3], and discovery of reasons for culling [1]. Decision trees and related methods have also been used for analysis of lactation curves [4], interpretation of somatic cell count data [5], and assessment of the efficiency of reproductive management [6, 7]. In addition, ANN have been used for the prediction of total farm milk production [8], prediction of 305-day milk yield [9, 10], and detection of mastitis [11, 12]. Fuzzy logic, which involves classification of variables into fuzzy sets with degrees of membership between 0 and 1, has recently found its way into agricultural research [13, 14]. Applications have included development of decision-support systems for analyzing test-day milk yield data from Dairy Herd Improvement (DHI) programs [15]. Detection of mastitis and estrus from automated milking systems [16, 17], and definition of contemporary groups for the
Study of Fatty Liver Syndrome Frequency in Dairy Cattle by Assessment of TG, APO-A and APO-B Serum Values in Tabriz
Amirparviz Rezaeisaber,Mehrdad Nazeri
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.339.342
Abstract: Fatty liver syndrome (Hepatic lipidosis) or fat cow syndrome is a major metabolic disorder in many dairy cattle s in early period of lactation. The aim of this study was to evaluating fatty liver syndrome in dairy cattle in Tabriz by measurement of TG, APO-A and APO-B serum values. The results showed that TG has a negative correlation with APO-A and APO-B. Thus with elevating of TG serum values, APO-A and APO-B contrary diminished.
Fatty Liver Syndrome in Dairy Cattle: Relation between Nefa, Apo-A, Ammoniac, Tsh and Total Bilirobin Serum Values in this Syndrom
Amir Parviz Rezaei Saber,Mehrdad Nazeri
International Journal of Animal and Veterinary Advances , 2012,
Abstract: Fatty liver syndrome (Hepatic lipidosis) or fat cow syndrome is a major metabolic disorder in many dairy cattle's in early period of lactation. The aim of this study was to evaluating fatty liver syndrome in dairy cattle in Tabriz by measurement of NEFA, APO-A, Ammoniac, TSH and Total Bilirobin serum values. In this study 10 mL blood samples from 400 Holstein dairy cows were obtained by venoject from jugular vein and then samples in vicinity of the ice sent to the laboratory. In lab, prepared serums froze inside the micro tube. The results showed that NEFA has a positive relationship with ammoniac and total Bilirobin serum values and reverse relationship with APO-A and TSH. Thus, with elevating of NEFA serum values, ammoniac and total Bilirobin also increased and TSH and APO-A contrary diminished.
Use of Different Methods for Estimation of Breeding Values and Estimation of Phenotypic and Genetic Parameters in Dairy Cattle  [PDF]
N. Akman,A. Ozyurt
Journal of Tekirdag Agricultural Faculty , 2009,
Abstract: In this study, a total of 2237 lactation records were used from 1034 female offspring of 26 bulls sired in Holstein Friesian dairy herd raising Polatl State Farm between 1985-1994. The records from 854 female offsprings of 26 bulls were used for the analysis of the first lactation and that of milk yield concerning 120 days. The breeding values (11 BV for bull, 12 BV for cow) were estimated by using different methods (Contemporary Comparison-CC, Herdmate Comparison-HC, Best Linear Unbiased Prediction-BLUP, Multiple Trait Derivative Free Restricted Maximum Likelihood- MTDFREML and Most Probable Producing Ability - MPPA). The heritability of first, partial and repeated lactation milk yield, the duration of lactation and the repeatability of milk yield were estimated respectively as 0.206±0.097, 0.249±0.101, 0.133±0.045, 0.057±0.039 and 0.337±0.025. All correlations were found high and statiscally significant (P<0.01). It is revealed that, not only new methods which need developed computer program but olso classical methods are effective for the prediction of the breeding value.
Ammonia Emissions from Dairy Cattle Barns in Summer Season
Ercan Simsek,Ilker Kilic,Erkan Yaslioglu,Ismet Arici
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.2116.2120
Abstract: The objective of this study was to determine magnitude of ammonia emissions from dairy cattle free-stall barns with natural ventilation. The measurements of ammonia concentration and indoor environmental conditions in barns were done throughout the 4 days in three dairy farms in summer season. The overall hourly average temperature and relative humidity for all barns were 26.5°C and 61%, respectively. In monitored dairy cattle barns, ammonia concentrations were observed between 0.4 and 8.77 ppm. The overall hourly average ammonia emission was calculated as 56.1 g/h.barn. Ammonia concentrations increased with lower airflow rate while ammonia emissions increased with higher airflow rate. As a result of this study, there is no significant relationship observed between ammonia emission and indoor environmental conditions such as temperature and relative humidity.
The mathematical description of lactation curves in dairy cattle  [cached]
Nicolò P.P. Macciotta,Corrado Dimauro,Salvatore P.G. Rassu,Roberto Steri
Italian Journal of Animal Science , 2011, DOI: 10.4081/ijas.2011.e51
Abstract: This review gives an overview of the mathematical modelling of lactation curves in dairy cattle. Over the last ninety years, the development of this field of study has followed the main requirements of the dairy cattle industry. Non-linear parametric functions have represented the preferred tools for modelling average curves of homogeneous groups of animals, with the main aim of predicting yields for management purposes. The increased availability of records per individual lactations and the genetic evaluation based on test day records has shifted the interest of modellers towards more flexible and general linear functions, as polynomials or splines. Thus the main interest of modelling is no longer the reconstruction of the general pattern of the phenomenon but the fitting of individual deviations from an average curve. Other specific approaches based on the modelling of the correlation structure of test day records within lactation, such as mixed linear models or principal component analysis, have been used to test the statistical significance of fixed effects in dairy experiments or to create new variables expressing main lactation curve traits. The adequacy of a model is not an absolute requisite, because it has to be assessed according to the specific purpose it is used for. Occurrence of extended lactations and of new productive and functional traits to be described and the increase of records coming from automatic milking systems likely will represent some of the future challenges for the mathematical modelling of the lactation curve in dairy cattle.
A Comparison of Scale on Profitability of Dairy Cattle Farms in Eastern Part of Turkey
Kasim Sahin
Journal of Animal and Veterinary Advances , 2012,
Abstract: The main objective of this study, was to determine the profitability of dairy operations in the province of Van (A province in eastern part of Turkey). A total of 117 dairy farmers were interview and data were collected about their operations. Dairy operations were divided into 3 groups based on their size, namely small, mid and large. All of data belongs to year 2007. The average cow per farm was 6.59. The daily milk yield per cow was 5.79 kg, overall, the average lactation period was 281.85 days for farms and yearly milk production per cow was 1630.9 kg. Total assets per farm were $ 16789, gross production value per farm was $ 8824 and per cow was $ 1339. Overall, gross profit per farm was $ 1863.1 and net profit per farm was $ 393 for farms. Overall, profitability rate was 2.2% for farms and increased in proportion to dairy cattle farm size. The total production elasticities of inputs were 0.851 indicating that there were decreasing return to scale for dairy cattle farms.
Scaling behaviour in daily air humidity fluctuations  [PDF]
Gabor Vattay,Andrea Harnos
Physics , 1993, DOI: 10.1103/PhysRevLett.73.768
Abstract: We show that the daily average air humidity fluctuations exhibit non-trivial $1/f^{\alpha}$ behaviour which different from the spectral properties of other meteorological quantities. This feature and the fractal spatial strucure found in clouds make it plausible to regard air humidity fluctuations as a manifestation of self-organized criticality. We give arguments why the dynamics in air humidity can be similar to those in sandpile models of SOC.
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