Abstract The effects of high dietary levels of fresh or moderately oxidised fish oilon performance and blood parameters in mink females were investigated during the winter,reproduction, and lactation periods. Furthermore, the effects of the diets on kit performance wereinvestigated during the lactation and early growth periods. The investigation was carried out with atotal of 292 females distributed in five experimental groups fed fresh fish oil stored frozen,fresh fish oil ensiled, oxidised fish oil stored frozen,. oxidised fish oil ensiled, and soya oil,respectively. The females were weighed three times during the winter period, and the females and thekits were weighed at parturition and 2, 4, and 7 weeks post partum. Blood samples were collectedfrom the females and the kits 6 and 8 weeks post partum, respectively. The results show that highdietary levels of fresh or moderately oxidised fish oil could be used for mink females during thewinter and reproduction periods without any negative effects on performance, health and reproductionresults. However, high levels of fish oil resulted in lower kit weights at weaning. These negativeeffects on kit growth were related to the dietary composition fed during the lactation and earlygrowth periods and not to the diet used during the preceding winter and pregnancy periods. A highintake of polyunsaturated fatty acids resulted in a decreased number of blood platelets for bothmink females and their kits.

Keywords Haematological indices; Kit growth; Mink kits; Platelets; Reproduction;Growing-furring period; Polyunsaturated fatty-acids; Vitamin-e; Clinical-chemistry; Supplementation;Inclusion; Products; Acetate; Health

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 3, 2003, Pages 136-146

Abstract The effects of carbohydrate-free diets on body weight changes, feedconsumption, and plasma concentrations of nutrients, metabolites, and hormones in lactating mink andon growth performance in kits were investigated in a total of 108 litters during the lactationperiod of seven weeks. The litters were distributed in three experimental groups fed differentratios of metabolisable energy (ME) derived from protein and fat (61:38; 47:52; 33:66). The femalesand kits were weighed at parturition and 2, 3, 4, and 7 weeks after parturition. Blood samples werecollected from females in the second, fourth, and sixth week of the lactation period.Carbohydrate-free diets fed to lactating mink can in principle support normal performance, health ofthe females, and growth performance of the kits. However, mink need a sufficient supply ofavailable gluconeogenic precursors in the form of amino acids. In the present experiment, the dietwith 33% of ME from protein contained insufficient amounts of gluconeogenic precursors for lactatingmink, and three weeks post partum this group was excluded from the experiment. The differences indietary protein level (61% and 47% of ME) and fat level (38% and 52% of ME) influenced the plasmaconcentrations of free fatty acids (FFA) and urea, but had minimal influence on plasmaconcentrations of other nutrients, metabolites, and hormones.

Keywords Body weight changes; Ffa; Plasma metabolites and hormones; Protein and;Weight changes; Protein; Period; Fat

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 3, 2003, Pages 127-135

Abstract A study of ewe performance was undertaken in 795 sheep flocks based on datafrom the Norwegian Sheep Recording System. Herd level data included in the annual report for 1998were used as the basis for the study Average flock size was 75.3 ewes. The material was consideredas representative of the better and more motivated sheep farmers in the mountain valley regions insouth-eastern Norway. The average number of lambs born per ewe, inclusive (and exclusive) of barrenewes, was 1.89 (2.02), and of autumn lambs (those surviving from birth in the spring to autumn) 1.60(1.66). The average autumn weight of the lambs corrected to 145 days of age was 42.4 kg, giving anoverall performance of 67.9 kg lambs live weight per ewe. When including artificially reared lambs,overall performance was 70.4 kg per ewe.

Keywords Epidemiology; Ewe performance; Lamb mortality; Sheep production

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 3, 2003, Pages 120-126

Abstract This experiment was carried out to examine the effects of energy level andenzyme supplementation of wheat-based diets compared with corn in laying hen diets on henperformance and egg quality. Experiment was conducted over 16 weeks with 27-wk-old Hisex Brownlaying hens. Hens were randomly assigned to five experimental diets in a single isolated controlgroup-2 (energy level) x 2 (enzyme supplementation)-factorial arrangement. Experimental groupsconsisted of corn diet (control), and wheat-based (600 g kg(-1)) diets at the normal (11.51 MJ/kgME, identical with the corn diet) and low energy levels (11.05 MJ/kg ME) with or without enzymesupplementation. Diets were fed in mash form. No significant interactions between energy level andenzyme supplementation on hen performance were observed. However, enzyme addition to wheat-baseddiets significantly improved laying rate, eggs mass and feed efficiency: the results were similar tothose of hens fed the corn diet. Final body weight gain, egg shape index, breaking strength, shellthickness and incidence of dirty eggs were not significantly affected by the dietary energy leveland enzyme supplementation. In the wheat-based diets, dirty eggs rate (2.07%) was higher than in thecorn diet (0.21%). There was no significant interaction between energy level and enzymesupplementation for egg yolk colour but enzyme addition to wheat-based diets increased egg yolkpigmentation, which was also lower than that of the corn diet. These results demonstrated that wheatcan replace corn in layer diets, and the addition of enzyme to wheat-based diets improved henperformance and egg yolk pigmentation. Energy enhancement of wheat by enzyme addition should beconsidered to achieve production and cost improvements in the formulation of layer diets.

Keywords Cereal; Xylanase; Egg production; Feed efficiency; Egg yolk colour;Beta-glucanase; Laying hen; Intestinal viscosity; Broiler chicks; Rye; diets; Barley; Availability;Bird; Age

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 3, 2003, Pages 113-119

Abstract The size and composition of the nematode assemblage in soil under faecal patsderived from young cattle treated or untreated with either ivermectin sustained-release boluses, orthe nematophagous fungus Duddingtonia flagrans , were studied in each of three years. Soil samplestaken 4, 6, 8 and 10 weeks after four deposition dates in 1998 showed significant temporal effectsin many taxa and treatment effects in a few genera. In 2000, soil samples taken 10 weeks afterdeposition in July, August and September showed treatment effects in the plant-associated Tylenchusand Cephalenchus , and the bacterial-feeding Cephalobus 1 and Cephalobus 2 taxa. However, overall itwas found that the nematode assemblages were similar below all three types of pat, and theassemblages varied with the season of deposition. D. flagrans , the novel biological control agentbeing tested against the free-living stages of nematode parasites of cattle, had no detectableimpact on the size or the structure of the soil nematode communities under the faecal pats.

Keywords Bacterial-feeding nematodes; Cephalobidae; Duddingtonia flagrans;Free-livingstages; Environmental-impact; Sheep; Sweden; Persistence;Avermectins; Efficacy; Pasture; Growth

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 197-206

Abstract In Denmark, organic feeding is typically based on homegrown feed with a highproportion of roughage. Which crop to grow and use as supplementary feed is investigated in thispaper. In three experiments, barley (B) was compared with another type of supplementary feed: aconcentrate mixture (C), grass pellets (G), or fodder beets (F). The concentrate mixture resulted ina higher (P = 0.002) milk yield (25.9 vs. 23.7 kg), a tendency of a lower ( P = 0.07) fat content(4.08 vs. 4.25%), and a higher (P = 0.006) ECM yield (25.7 vs. 24.1 kg) compared to feeding barleyas supplement at the same energy level. Grass pellets resulted in a lower (P = 0.01) milk fatcontent (3.74 vs. 4.07%), a tendency of a lower (P = 0.12) protein content (3.14 vs. 3.23%), but nodifferent milk or ECM yield compared to feeding barley as supplement at the same dry matter level.Fodder beet tended to decrease (P = 0.12) the milk yield (20.7 vs. 22.0 kg), and the ECM yield (P =0.05) was lower (21.5 vs. 22.9 kg) whereas the composition of the milk was unaffected compared tothe total mixed ration with barley.

Keywords Health; Homegrown; Milk yield; Organic feeding; Supplementaryfeed;Dietary-protein concentration; Milk-production; Early lactation;Cattle; Fiber; Performance;Digestion; Passage; Starchy; Level

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 186-196

Abstract This study was the first to analyze the polymorphic characteristics of a widerange of genetic markers in three Lithuanian horse breeds. Genetic variation at seven red bloodcell alloantigen (blood group) loci, 10 biochemical genetic loci and 16 microsatellites wasexaminated in 31 Zemaitukai, 30 large-type Zemaitukai and 24 Lithuanian Heavy Draught horse andcompared to that of other domestic horse breeds. Genetic variability of the Zemaitukai breeds basedupon blood groups and biochemical loci was higher than average for domestic horse breeds. Formicrosatellite loci, the variability of the large-type Zemaitukai and the Heavy Draught breeds alsowas high compared to the mean variation for domestic breeds; however, for the Zemaitukai breed,variation levels were very near the average for horses.

Keywords Blood groups; Genetic similarity; Genetic variation; Microsatellite;Highlypolymorphic microsatellites; Blood groups; Frequencies; Markers

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 180-185

Abstract Unlike most domestic livestock species, sheep are widely known as animalswith marked seasonality of breeding activity. The annual cycle of the daily photoperiod has beenidentified as the determinant factor of this phenomenon, while environmental temperature,nutritional status and social interactions may modulate it. The aim of this paper is to review thecurrent state of knowledge of reproductive seasonality in sheep. Following general consideration ofthe importance of seasonal breeding as a reproductive strategy for the survival of the species, thepaper describes manifestations of seasonality in both the ram and the ewe. Both determinant andmodulating factors are discussed, and special emphasis is given to the neuroendocrine base ofphotoperiodic regulation of seasonal breeding. Other aspects such as the role of melatonin, theprogestogens and ram effects with or without anestrus period are also reviewed.

Keywords Anestrus; Melatonin; Photoperiod; Ram effect; Reproduction; Sheep;Ewe lambs;Corpus-luteum; Estrus; Ovulation; Synchronization; Ram;Performance; Melatonin; Fsh; Progesterone

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 175-179

Abstract The objective of the study was to compare production results andtechnological meat quality for pigs born outdoors and reared indoors or outdoors during the summerperiod. A total of 279 pigs was reared in a large pen on deep litter, or outdoors. Daily weight gainand lean meat percentage were higher for pigs outdoors than indoors during year one (864 vs. 841g;56.9 vs. 55.9%), but were similar for year two (859 vs. 844g; 55.9 vs. 55.6%). Outdoor pigs grewfaster when fed ad libitum , but slower during the second phase when restricted, with inferior feedconversion. Most technological meat quality traits (surface and internal reflectance, marbling, pHBF , filter paper wetness, cooking loss and maximal Warner-Bratzler shear force) were similarbetween rearing systems, whereas pH LD was higher indoors. Total work of Warner-Bratzler shear forcewas lower in outdoor reared pigs. Maternal sire breed (Duroc or Landrace) and sex (castrate orgilt) did not notably affect meat quality traits. RN genotype had a stronger impact on meat qualitythan rearing system. It can be concluded from the similarities in production results and meatquality in both systems, that both indoor and outdoor rearing are good alternatives for summerrearing of pigs.

Keywords Carcass traits; Growth; Organic production; Pork; Swine;Post-weaningbehavior; Carcass composition; Muscle; Performance;Growth; Environment; Hampshire; Traits; Level;Sire

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 166-174

Abstract It is believed that some Finnish farmed “Wild Boars” may not originate fromgenuine European Wild Boar. To test this the D-loop mitochondrial sequence and nuclearglucosephosphate isomerase processed pseudogene (GPIP) and melanocortin receptor 1 (MC1R) genes wereanalysed in 41 Finnish farmed Wild Boar from two farms in order to determine if there was anyevidence of hybrid origins. D-loop sequences clustered with European domestic pigs and northernEuropean Wild Boars. On one farm, animals had both European and Asian/European GPIP genotypessuggestive of crossbreeding, while on the other, animals had exclusively European GPIP alleles. Oneanimal from the first farm also had a MC1R genotype, strongly indicative of crossbreeding withEuropean domestic pigs while the other 40 animals showed MC1R genotypes expected for genuineEuropean Wild Boar. Joint consideration of all markers suggests that domestic pigs may havecontributed to the origins of the “Wild Boar” on one of the farms.

Keywords D-loop; Gpip; Mc1r;D-loop region; Mitochondrial-dna; Sus scrofa; Origin;Polymorphism;Sequences; Breeds

Acta agriculturae Scandinavica. Section A, Animal science
0906-4702, Volume 53, Issue 4, 2003, Pages 161-165