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Characteristics of feeding and breeding practices for intensification of smallholder dairy systems in the Kenya highlands
2008
Bebe, B.O. | Udo, H.M.J. | Thorpe, W.R.
This study aimed at better understanding of the characteristics of feeding and breeding practices smallholder farmers adopt in intensifying their dairy production. Use of hired labour for fodder gathering, growing of fodder crops and purchase of feeds increased with increasing intensification, but Bos taurus breeds did not respond to increasing feeding intensification while Bos indicus cattle responded, calving at earlier age and yielding more milk. Overall, first calving occurred at 32 months, but days open prolonged to 250 days with milk yield of 4 litres per day of calving interval. A principal component analysis extracted six feeding and breeding components, explaining 71.79% of the total variations in feeding and breeding practices for dairy intensification. The six components were labelled: non-intensified feeding and breeding; breeding decisions based-intensification; high external resource based-intensification; moderate resource based-intensification; resource poor based-intensification; and moderate external resource based-intensification. These characteristics points to some 'evolutionary process' of intensification involving feeding and breeding decisions, depending on the risk-bearing capacity of the household. Intensification enhancing interventions for smallholders need be considered in the context of the household economy. Interventions on feeding and breeding have to be packaged together holistically if intensification is to enhance productivity. A selective intervention on only one of these is associated with low productivity levels, only contributing to sustaining family subsistence livelihoods.
显示更多 [+] 显示较少 [-]Genetic evaluation of dairy cattle using test day yields
2006
Zutere, R.
Genetic evaluation of dairy cattle for milk production based on 305-day lactation yields was compared to the evaluation based on the corresponding test day (TD) yields from the first lactation. The heritability estimates were 0.19, 0.13 and 0.15, respectively for milk yield, fat yield and protein yield, and these parameters are lower than the corresponding ones for the routine genetic evaluation with the lactation model in Latvia. The results of estimated breeding values (EBV) and relative breeding values (RBV) showed relatively high variance for all traits: higher for fat yield and lower for protein yield. The calculation of reliabilities showed that the use of test day model gives higher reliabilities of the estimated breeding values. The reliabilities are higher (about 2 - 4 %) for all traits using TD model on average for all animals and cows. For bulls group with calculated reliabilities of breeding values of at least 50 % for all traits, the measure of accuracy is higher with TD model from 7% for protein yield to 17% for fat yield. The ranking of the best Top 10 sires by TD model is similar to the lactation model. A total of 3 bulls for fat and protein yield are included in rankings of Top 10 both by TD and lactation models. TD yields could be used instead of 305-day yields for the genetic evaluation of dairy cattle. It helps to improve the accuracy of genetic evaluation and does not change ranking of the best sires drastically.
显示更多 [+] 显示较少 [-]Milk production, dry matter intake and fertility in first-parity cows bred in Estonia
2002
Kaert, O. | Saveli, O. | Ling, K. | Samaruetel, J. | Jaakson, H. (Estonian Agricultural Univ., Tartu (Estonia))
The goal of this study was to investigate the use of body reserves, energy balance and fertility parameters at the beginning of lactation in first-parity cows bred in Estonia.
显示更多 [+] 显示较少 [-][Evaluation of farmer milk production. Case of two communities of Toluca Valley, Mexico State] | Caracterizacion y evaluacion de los sistemas campesinos de produccion de leche. El caso de dos comunidades del Valle de Toluca
1997
Castelan Ortega, Octavio Alonso | Mathewman, Richard W. | Fawcett, Roy | Smith, Anthony | Gonzalez Martinez, Eloy | Burgos Garcia, Ramon | Cruz Juarez, Daniel de la
Factors affecting milk calcium and phosphorus content
2002
Kuebarsepp, I. | Henno, M. | Kaert, O. (Estonian Agricultural Univ., Tartu (Estonia))
The purpose of this study to compare milk calcium and phosphorus content of different breeds raised in Estonia. Based on obtained results, different factors and their magnitude of influence on the contents of calcium and phosphorus in milk were studied. On Polula Research Farm five trial groups were made up: Estonian Holstein breed (breeding value 115) (EHF-t), Estonian Holstein breed (breeding value 105...115) (EHF), Red-and-White Holstein breed (RHF), Estonian Red breed (EPK) and Estonian Native breed (EK). Milk samples were collected from five of each trial group twice a month during the year 2001. Calcium and phosphorus contents were determined by using IDF methods 36A:1992 and 42B:1990 in Dairy Laboratory of the Institute of Animal Science.
显示更多 [+] 显示较少 [-][Methodology in the participative research of dairy farmers system of Mexico State] | Metodologia de investigacion participativa rural de sistemas campesinos de produccion de leche en el estado de Mexico
1997
Arriaga Jordan, Carlos | Espinoza Ortega, Angelica | Castelan Ortega, Octavio Alonso | Sanchez Vera, Ernesto
[Rural participative research in the improvement of milk production systems in small scale in Mexico State] | Resultados de investigacion participativa rural en el mejoramiento de sistemas de produccion de leche en pequena escala en el estado de Mexico
1997
Arriaga Jordan, Carlos | Espinoza Ortega, Angelica | Castelan Ortega, Octavio Alonso | Rojo Guadarrama, Heidy | Valdes Martinez, Jose Luis | Albarran Portillo, Benito
[The use of formal and informal approaches in the investigation of agricultural production systems. Case of farmer milk production] | El uso de enfoques formales e informales en la investigacion en sistemas de produccion agropecuarios. El caso de la produccion campesina de leche
1997
Castelan Ortega, Octavio Alonso | Arriaga Jordan, Carlos | Fawcett, Roy