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  • Survival analysis of sow longevity and lifetime reproductive performance – Review
    75-80
    Views:
    319

    Sow longevity plays an important role in economically efficient piglet production. Improving sow longevity results increase in the productivity and profitability of a sow herd. Longevity is a complex trait with many factors that can contribute to a sow having a long and productive life. Not only the sow’s genetics, but also nutrition, environment and the management policies are important. In addition, the removal of non-productive sows along with the introduction of replacement gilts is an essential part of maintaining herd productivity at a constantly high level. The objective of this paper was to summarize the current knowledge about the sow longevity and lifetime performance values, as well as, discusses the survival analysis methods for sow longevity traits. This method can estimate the hazard rate indicating proportional risk of sows being culled at any given time, in addition, it is able to investigate the effects of different factors on longevity. Identifying factors that influence the longevity could assist many commercial pig producers in becoming more efficient.

  • Analysis of longevity in Holstein Friesian cattle using proteomic approaches
    21-25
    Views:
    210

    The aim of the present study was to determine marker proteins those are associated with functional longevity of dairy cattle. Holstein-Friesian cows were grouped based on their performance as follows: group 1) individuals with good longevity traits; group 2) short production life because of poor reproduction traits; group 3) short production life with low milk yield. Twelve individuals were sampled in each group, blood and milk samples were collected from cows. Blood samples were analysed with two dimensional polyacrylamide gel electrophoresis (2D PAGE), MALDI TOF/TOF and nanoLCMS/MS. The milk samples were analysed with MALDI TOF/TOF and nanoLC-MS/MS. Using the optimized gel based proteomic approach,
    we have succesfully separated 143 proteins in the group1, 139 proteins in the group2 and 136 proteins in the group3, but we could not find significant differences between groups in the expression pattern. Using MALDI TOF/TOF and nanoLC-IonTrap MS, we have found eleven protein sequences those were expressed only in the samples of good longevity group.

  • Evaluation of the relationship between main type traits and longevity in Hungarian Simmental cows
    205-209
    Views:
    152

    The Hungarian Simmental cattle is a dual-purpose breed, having good milk and meat production characteristics. Simmental cows have some other important traits, for example, a longer productive life. The longevity or productive life is the time period between first calving and culling. The conformation contributes to productive life, reproduction, and milk production.

    The aims of this study were to analyze the longevity of Hungarian Simmental dual-purpose cows, to evaluate the effects of the size of the herd, age at first calving, main type traits (frame, musculature, feet and legs, mammary system), and combination of main type traits (frame and musculature, feet and legs and mammary system).

    Animal, age at first calving, herd*calving, musculature, the mammary system as well as the combination of mammary system and feet and legs were significant effects on longevity. The highest risk ratio was observed for cows first calved after 31 months. The risk of culling increased with increasing scores of musculature and decreasing scores of the mammary system. The highest risk ratio was estimated in category 11 (lower scores of mammary system with lower scores of feet and legs). In this case, the risk ratio was 36% higher than the reference group.

  • Determining the optimal age of breeding gilts and its impact on lifetime performance, Literature review
    15-20
    Views:
    555

    Lifetime sow performance is a critical indicator for producers managing a commercial sow herd. It is comprised of sow longevity, lifetime piglets born alive, lifetime number of pigs weaned and lifetime non-productive sow days. Increased lifetime performance and longevity in sows reduces costs of replacement gilts and improves herd performance and profitability (Sasaki et al., 2008, 2011). One of the most critical factors driving the performance of sow herds is gilt management. Decisions regarding gilts have profound effects on sows’ lifetime performance. Age at first breeding of a gilt is a management decision that has been shown to affect performance and retention of the gilt in a herd.

    The main aim of this review is to establish factors affecting age of first breeding of gilts and its impact on lifetime performance.