Prediction Models for Age-at-Death Estimates for Calves, Using Unfused Epiphyses and Diaphyses

Abstract

International audienceFor cattle (Bos taurus), age estimations using dental criteria before the eruption of the first molar (3–8 months) have large error margins. This hampers archaeozoological investigation into perinatal mortality or the putative slaughtering of very young calves for milk exploitation. Previous ageing methods for subjuveniles have focused on the length of unfused bones, but it is rarely possible to use them because they are restricted to foetuses and because of the fragmentation of bones. This paper presents new age prediction models based on length, breadth and depth of post cranial bones produced from a dataset of modern calves (n = 27). This reference collection was compiled from material of known age at death, sex and breed from collections in Britain, France, Germany and Switzerland. Linear regression models were constructed using the modern data for age prediction, and these models were then successfully tested and assessed using a Middle Neolithic assemblage of complete calves' skeletons from Bourguignon-Lès-Morey, France. From the assessment, the astragalus and metapodials were determined to be the most reliable bones, and the femur was the worst. Measurements of the epiphyseal and distal elements and depth measurements were the most reliable. For ages before 12 months, these models can provide ±1 month age estimates. Copyright © 2013 John Wiley & Sons, Ltd

The evolution of dual meat and milk cattle husbandry in Linearbandkeramik societies

“…M1 and M2 were differentiated using the distance anterior to posterior (DAP) and distance transverse (DT). Legge [ 35 ] age classes were used as they have been found to be more accurate [ 39 ]. Teeth were attributed to each age class following Legge [ 35 ].…”

Holocene resource exploitation along the Nile: diet and subsistence strategies of Mesolithic and Neolithic societies at Khor Shambat 1, Sudan

“…The limited size of the assemblage precludes full reconstruction of an age-at-death profile, but mature animals (above four years of age) were preferentially slaughtered, suggesting that cattle and small ruminants were bred mostly for secondary products, such as milk (Balasse 2003; Gillis et al . 2013). All parts of the animals were used and bone shafts were broken to obtain marrow.…”

Neonatal Mortality, Young Calf Slaughter and Milk Production during the Early Neolithic of North Western Mediterranean

“…There are some discrepancies for eruption timings for M1 between different authors (Silver, 1963: 5-6 months;Legge, 1992: 2-3 months). Gillis et al (2013a) have demonstrated that the absolute age references given by Legge (Legge, 1992) are more accurate than those based on traditional veterinarian observations of tooth eruption through the gum (Silver, 1963;Higham, 1967). In addition, to Legge's (Legge, 1992) scheme, crown height ratios were used to identify adult mortality following …”

“…Distinguishing neonatal mortality from deliberate slaughter was not possible until recently as there were no means of predicting the age-at-death of calves with narrow standard errors. Here we take advantage of the recent publication of predicting age-atdeath (AtD) from un-fused post-cranial bone measurements (Gillis et al, 2013a) together with dental AtD frequencies to investigate neonatal mortality and young calves culls (<6 months) at two sites in the North-Western Mediterranean region: Trasano and La Draga.…”

“…Estimates of AtD from bone epiphyseal fusion events begin at 7 months, which excludes examination of the perinatal mortality. Gillis et al (2013a) have developed linear models for the prediction of AtD from measurements following von den Dreisch (von den Driesch, 1976; GL, Bp, Dp, SD, Bd and Dd) of un-fused diaphyses and epiphyses of post-cranial long bones as well as astragalus and calcaneus. The post-cranial elements studied for each site are detailed in Table 2.…”