16 research outputs found
Carcass records of autumn-slaughtered reindeer as indicator of long-term changes in animal condition
This study investigates the possibility of using carcass records from the commercial slaughter of reindeer as indicator of long-term changes in animal condition and, thus, the condition and use of their snow-free pasture. The aim was to assess the suitability of this indicator for use within adaptive management programmes for reindeer husbandry grazing resources. Data comprising measurements of carcass weight, conformation and fatness taken from commercial reindeer slaughter between 1994 and 2007, were analysed in relation to year, slaughter date, herding district, population density, and three categories of animals selected for slaughter. The carcass measures were significantly affected by year, and the effects were strongly correlated among the three animal categories. There were generally positive trends over the 14-year period studied. We identified several factors that should be considered when using carcass data to indicate long-term changes in animal body condition: (i) slaughter date had different effects depending on animal category; (ii) reindeer population density negatively affected female and calf carcasses, but not male carcasses. The effects of herding district were similar for carcasses of calves and females, but differed between females and males. Some of the differences between animal categories may be due to differing timing of slaughter (point i above), by different slaughter selection among districts, or have ecological explanations, e.g. sex differences in range use. Uncertainties in the classification of animals when using skeletal development to discriminate between calf and yearling carcasses, may also add to differences among districts. That population density effects on body condition were detectable together with the similarities in the effects of year and general long-term trends between animal categories support the suggestion that carcass measures can be used to indicate general changes in reindeer body condition and range use
Approaches to estimate body condition from slaughter records in reindeer
Long-term fluctuations in population densities of reindeer and caribou are common, where pasture is the limiting resource. Pasture quality affects the nutritional status and production of the animals. Therefore, continuous information about changes in the grazing resources is important when making management decisions. The objective of this study was to investigate different possibilities of using routine and additional slaughter records as body condition indicators, and thereby indicators of pasture resources in the summer ranges of reindeer husbandry. Records from 696 reindeer slaughtered in the winter 2002/2003 were included in the study. We developed a model with carcass weight as body condition indicator and two different models combining fatness, conformation, carcass weight, and body size as body condition indicators. The results showed age and sex dependent differences between the variables, and differentiation of animal age and sex improved the precision of models. Adjusting weight for body size also improved weight as a body condition indicator in adults. Conformation and fatness had good resemblance to weight and body size adjusted weight and should preferably be included, together with carcass weight and body size measures, when estimating body condition from carcasses. Our analysis showed that using non-invasive slaughter records is a good and non-expensive method of estimating body condition in reindeer. Abstract in Swedish / Sammandrag:Tillvägagångssätt för skattning avkroppskondition hos ren från slaktregistreringarFluktuationer i ren- och caribou-populationers täthet över tiden är vanliga då betet är en begränsad resurs och beteskvalitén påverkar djurens kondition och produktion. Kontinuerligt uppdaterad information om förändringar i betesresurserna är viktigt i samband med beslutsfattande om förvaltning avresurserna. Syftet med denna studie var att utvärdera olika möjliga sätt att använda rutinregistreringar och extra registreringar vid slakt som konditionsindikatorer och därmed indikatorer för betestillstånd i sommarland inom rennäringen. Registreringar från 696 renar, slaktade under säsongen 2003/2003 användes i studien. Vi utvecklade en modell där slaktvikt var den enda indikatorn på kroppskondition, samt två modeller som kombinerade fett- och formklassificeringen med slaktvikt och kroppsstorlek som indikatorer på kroppskondition. Resultaten visade att renarnas ålder och kön ger skillnader i de olika variablerna och att modellernas noggrannhet ökar om djuren grupperas med tanke på ålder och kön. Att korrigera slaktvikten för kroppsstorlek ökade precisionen för vikt som konditionsindikator för vuxna djur. Fett- och formklassificeringen överensstämde väl med storlekskorrigerad slaktvikt och skulle med fördel kunna inkluderas tillsammans med slaktvikt och storlek för skattning avkroppskondition från slaktkroppar. Våra analyser visar att användning avslaktregistreringar är en bra och billig metod för att skatta kroppskonditionen hos renhjorden
Frequencies of genes for coat colour and horns in Nordic cattle breeds
Gene frequencies of coat colour and horn types were assessed in 22 Nordic cattle breeds in a project aimed at establishing genetic profiles of the breeds under study. The coat colour loci yielding information on genetic variation were: extension, agouti, spotting, brindle, dun dilution and colour sided. The polled locus was assessed for two alleles. A profound variation between breeds was observed in the frequencies of both colour and horn alleles, with the older breeds generally showing greater variation in observed colour, horn types and segregating alleles than the modern breeds. The correspondence between the present genetic distance matrix and previous molecular marker distance matrices was low (r = 0.08 â 0.12). The branching pattern of a neighbour-joining tree disagreed to some extent with the molecular data structure. The current data indicates that 70% of the total genetic variation could be explained by differences between the breeds, suggesting a much greater breed differentiation than typically found at protein and microsatellite loci. The marked differentiation of the cattle breeds and observed disagreements with the results from the previous molecular data in the topology of the phylogenetic trees are most likely a result of selection on phenotypic characters analysed in this study
Approaches to estimate body condition from slaughter records in reindeer
Long-term fluctuations in population densities of reindeer and caribou are common, where pasture is the limiting resource. Pasture quality affects the nutritional status and production of the animals. Therefore, continuous information about changes in the grazing resources is important when making management decisions. The objective of this study was to investigate different possibilities of using routine and additional slaughter records as body condition indicators, and thereby indicators of pasture resources in the summer ranges of reindeer husbandry. Records from 696 reindeer slaughtered in the winter 2002/2003 were included in the study. We developed a model with carcass weight as body condition indicator and two different models combining fatness, conformation, carcass weight, and body size as body condition indicators. The results showed age and sex dependent differences between the variables, and differentiation of animal age and sex improved the precision of models. Adjusting weight for body size also improved weight as a body condition indicator in adults. Conformation and fatness had good resemblance to weight and body size adjusted weight and should preferably be included, together with carcass weight and body size measures, when estimating body condition from carcasses. Our analysis showed that using non-invasive slaughter records is a good and non-expensive method of estimating body condition in reindeer.
Abstract in Swedish / Sammandrag:
TillvÀgagÄngssÀtt för skattning avkroppskondition hos ren frÄn slaktregistreringar
Fluktuationer i ren- och caribou-populationers tÀthet över tiden Àr vanliga dÄ betet Àr en begrÀnsad resurs och beteskvalitén pÄverkar djurens kondition och produktion. Kontinuerligt uppdaterad information om förÀndringar i betesresurserna Àr viktigt i samband med beslutsfattande om förvaltning avresurserna. Syftet med denna studie var att utvÀrdera olika möjliga sÀtt att anvÀnda rutinregistreringar och extra registreringar vid slakt som konditionsindikatorer och dÀrmed indikatorer för betestillstÄnd i sommarland inom rennÀringen. Registreringar frÄn 696 renar, slaktade under sÀsongen 2003/2003 anvÀndes i studien. Vi utvecklade en modell dÀr slaktvikt var den enda indikatorn pÄ kroppskondition, samt tvÄ modeller som kombinerade fett- och formklassificeringen med slaktvikt och kroppsstorlek som indikatorer pÄ kroppskondition. Resultaten visade att renarnas Älder och kön ger skillnader i de olika variablerna och att modellernas noggrannhet ökar om djuren grupperas med tanke pÄ Älder och kön. Att korrigera slaktvikten för kroppsstorlek ökade precisionen för vikt som konditionsindikator för vuxna djur. Fett- och formklassificeringen överensstÀmde vÀl med storlekskorrigerad slaktvikt och skulle med fördel kunna inkluderas tillsammans med slaktvikt och storlek för skattning avkroppskondition frÄn slaktkroppar. VÄra analyser visar att anvÀndning avslaktregistreringar Àr en bra och billig metod för att skatta kroppskonditionen hos renhjorden
Frequencies of genes for coat colour and horns in Nordic cattle breeds
Gene frequencies of coat colour and horn types were assessed in 22 Nordic
cattle breeds in a project aimed at establishing genetic profiles of the
breeds under study. The coat colour loci yielding information on genetic
variation were: extension, agouti, spotting, brindle, dun dilution
and colour sided. The polled locus was assessed for two
alleles. A profound variation between breeds was observed in the frequencies
of both colour and horn alleles, with the older breeds generally showing
greater variation in observed colour, horn types and segregating alleles
than the modern breeds. The correspondence between the present genetic
distance matrix and previous molecular marker distance matrices was low
. The branching pattern of a neighbour-joining tree
disagreed to some extent with the molecular data structure. The current
data indicates that 70% of the total genetic variation could be explained
by differences between the breeds, suggesting a much greater breed
differentiation than typically found at protein and microsatellite loci.
The marked differentiation of the cattle breeds and observed disagreements
with the results from the previous molecular data in the topology of the
phylogenetic trees are most likely a result of selection on phenotypic
characters analysed in this study.Fréquences génétiques pour la couleur de la robe et la présence de cornes
chez des races de bovins nordiques.
Dans le cadre d'un projet visant à établir leurs profils génétiques, on
a estimé les fréquences génétiques à des locus gouvernant la couleur de la
robe et la présence de cornes chez 22 races de bovins nordiques. Les locus
informatifs pour évaluer la variation génétique étaient extension,
agouti, spotting, brindle, dun dilution, colour sided et polled.
On a mis en évidence une importante variation des fréquences de ces gÚnes
entre les races, et les races les plus anciennes montraient généralement
plus de variation que les races modernes. La correspondance entre la matrice
des distances génétiques obtenue dans cette étude et celle trouvée précédemment
à partir de marqueurs moléculaires était faible . Le
dendrogramme obtenu à partir de la méthode du "neighbour-joining "comportait
certaines différences avec celui déjà construit à l'aide de marqueurs
moléculaires. Notre étude indique que 70 % de la variation génétique totale
pourrait ĂȘtre due aux diffĂ©rences entre les races, suggĂ©rant ainsi une
différenciation entre races plus forte que celle anticipée à partir des locus
de protéines ou des microsatellites. Ces différences entre les présents
résultats et ceux obtenus à partir d'autres marqueurs sont vraisemblablement
dues à la sélection qui a été menée sur les caractÚres phénotypiques correspondant
aux locus analysés dans ce travail