Evidence that leptin genotype is associated with fertility, growth, and milk production in Holstein cows

Abstract

This study investigated associations between single nucleotide polymorphisms (SNP) in the leptin, leptin receptor, and neuropeptide Y (NPY) genes with growth, milk production, and fertility traits. Holstein Friesian heifers from 19 UK dairy farms were recruited at birth, providing an initial population of 509. Animals were monitored until they either reached the end of their second lactation or were culled. Size (weight, height, length, girth) was measured at 1, 6, and 15 mo to assess growth traits. Heifer fertility was assessed by recording age at service, age at conception, age at first calving, and number of services. Cow fertility was assessed by recording days from calving to service and conception, services per conception, percentage of animals in calf at 100 d after calving and the calving interval in each lactation. Milk production was recorded as days in milk, total milk per lactation, 305-d yield, milk per day, and peak yield. Mixed model analyses revealed that leptin SNP were associated with early skeletal growth (height, A1457G; length, A59V), fertility (UASMS1, UASMS2, A1457G, A59V) and milk production (A59V). The leptin receptor SNP (T945M) was only weakly associated with milk per day and days to first service. The NPY SNP (NPY1) was associated with the prevalence of the animal being in calf 100 d after calving and 305-d milk yield in the first lactation. The association of leptin SNP with fertility traits in heifers, in addition to lactating cows, suggests that some effects on fertility are direct and not necessarily mediated via altered tissue mobilization. In accord with this, other work has shown that leptin can affect oocyte quality and early embryo development. These results support the use of leptin SNP to inform marker-assisted selection in dairy cows.

Associations between lipid metabolism and fertility in the dairy cow

“…In our study leptin SNPs were more strongly associated with fertility than with milk production (Clempson et al 2011b). Of five different leptin SNPs investigated, all were significantly associated with some aspect of fertility, including age at first service and services per conception in heifers, age at first calving, days to conception, proportion in-calf at 100 days post partum and calving interval.…”

“…In contrast, only one SNP in our study (A59V) was associated with milk yield, although other studies have found some associations of leptin SNPs with milk yield and composition (van der Lende et al 2005;Banos et al 2008). An SNP in neuropeptide (NPY) was also significantly associated with the in-calf rate at 100 days (Clempson et al 2011b). NPY is a neurotransmitter that controls appetite and energy homeostasis and is a key regulator of leptin activity in the hypothalamus (Bahar and Sweeney 2008).…”

Heifer fertility and carry over consequences for life time production in dairy and beef cattle

“…DeVuyst et al (2008) reported an association between a leptin SNP and weaning weight in crossbred calves, while polymorphisms in the leptin receptor were associated with growth traits in Nanyang cattle, where they had significant effects on height, length, heart girth, weight and ADG at 6 and 12 months of age (Guo et al, 2008). Mixed model analyses revealed that leptin SNP in Holstein-Friesian heifers were similarly associated with early skeletal growth and also with fertility and subsequent milk production (Clempson et al, 2011). The association of leptin SNP with fertility traits in heifers suggested that the actions on fertility were direct and not mediated via altered tissue mobilisation as might occur during lactation.…”

Polymorphisms of LEP, LGB and PRLR in water buffalo

“…LEP, the fat derived protein hormone, has a variety of physiological functions such as regulation of feed intake, energy balance, and fertility and immune functions (Tanpure et al, 2012). Genetic polymorphisms within the bovine LEP gene were found to be associated with growth, fertility and milk production in Holstein cows (Clempson et al, 2011;Tanpure et al, 2012).…”