Intermandibular width and and cannon bone length in “winners” versus “others”

Conformation is defined as the form or outline of an animal and is sometimes expanded to include a relationship of form to function. In the course ofa studentproject,25 traits were measured in each of 20 Thoroughbreds as 3-year-olds in training. "Winners" were three year olds who had won a listed race in 1990 as two year olds. "Others" were three year olds who had raced but not won in listed races in 1990 as two year olds. Twelve of these Waits were evaluated using a linear assessment scoring system; 13 traits were measured using a steel tape, vernier calipers or an improvised compass. This short communication confines itself to two measured waits, intermandibular width and cannon bone length.     

Selecting for changes in average “parity curve” pattern of litter size in Large White pigs

This study aimed to analyse genetic background of variation in reproductive performance between parities of a sow and to investigate selection strategies to change the “parity curve”. Total number born (TNB) recorded in Large White sows was provided by Topigs Norsvin. Analysis with basic (BM) and random regression (RRM) models was done in ASReml 4.1. The BM included only a fixed “parity curve”, while RRM included 3rd order polynomials for additive genetic and permanent sow effects. Parameters from RRM were used in simulations in SelAction 2.1. Based on Akaike information criterion, RRM was a better model for TNB data. Genetic variance and heritability estimates of TNB from BM and RRM were increasing with parity from parity 2. Genetically, parity 1 is the most different from parities 7 to 10, whereas most similar to parities 2 and 3. This indicates presence of genetic variation to change the “parity curve”. Based on simulations, the selection to increase litter size in parity 1 only increases TNB in all parities, but does not change the observed shape of “parity curve”, whereas selection for increased TNB in parity 1 and reduced TNB in parity 5 decreases differences between parities, but also reduces overall TNB in all parities. Changing the “parity curve” will be difficult as the genetic and phenotypic relationships between the parities are hard to overcome even when selecting for one parity.     

“Subnutrition effects during pregnancy and lactation on mitosis,apoptosis and androgen receptor expression in the rat testis”

In order to study the effect of undernutrition during gestation on the testicular development in rats and its impact on mitosis, apoptosis and the relative abundance of androgen receptor expression, twenty primiparous 3‐month‐old Sprague–Dawley (Rattus norvegicus) rats, weighing 246 ± 4.0 grams when the experiment began, were mated by the same male. Control group (CG), n = 10, fed ad libitum with water and rat chow and restricted group (RG, n = 10) fed throughout pregnancy and until birth with 40% of the ad libitum maternal daily feed intake. Litters from both groups suckled for 25 days, RG with 14 pups/litter and CG with 8 pups/litter. After weaning, all animals had access to ad libitum food and water. Testicular samples were taken from male pups at 2, 25 and 100 days of age. Immunohistochemistry was used to evidence androgen receptor (AR) expression in apoptotic (caspase 3‐positive) and proliferating (PCNA‐positive) cells. Three hundred nuclei of sustentacular (or Sertoli: SC), interstitial (or Leydig: LC), myoid (MC) cells as well as gonocytes (GC) were evaluated. Neither LC nor GC showed any differences between groups. However, SC androgen receptor (AR) positivity index in neonatal animals was lower in RG (1.27 ± 0.22 vs. 1.65 ± 0.17**). MC showed lower AR positivity index at 2 (2.69 ± 0.046 vs. 2.8 ± 0.055**) and 25 (1.34 ± 0.097 vs. 1.56 ± 0.1***) days of life; at 100 days of life, there was a greater number of apoptotic MC in the RG (8.5 ± 0.4 vs. 2.95 ± 1.1***). Thus, the present experiment demonstrates that the population dynamics of MC are affected by foetal programming due to undernutrition.     

Discrimination of “grazing milk” using milk fatty acid profile in the grassland dairy area in Hokkaido

Milk produced by the grazing system, referred to as “grazing milk” contains many components required for human health. The milk fatty acid (FA) profile is strongly associated with the diet on the farms. In the present study, based on the FA profile of farmer's bulk milk, we determined how to discriminate between milk produced on grazing and on a confinement system. A field survey was conducted four times (grazing and confinement season) in the Konsen (29 farms) and Okhotsk (25 farms) area in Hokkaido. Farmer's bulk milk samples and details of feeding management were collected and the FA profile of milk was measured. Milk produced during the grazing season contained less C16:0 and cis‐9 C16:0, and more C18:0, cis‐9 C18:1, trans‐11 C18:1, cis‐9,12 C18:2, cis‐9,trans‐11 C18:2 and cis‐9,12,15 C18:3 than milk produced during the confinement season. Discrimination analysis using 16 FA revealed that almost all milk samples were discriminated correctly (confinement season: 90% correct and 10% borderline, grazing season: 88% correct, 9% borderline and 3% incorrect). For farmers that were categorized incorrectly and were considered borderline in the grazing season, the dependency on pasture was low compared with that for farmers correctly discriminated. Therefore, to claim “grazing milk”, a high dependency on pasture is required for grazing dairy farmers.