ABSOLUTE AND
RELATIVE FECUNDITY, EGG WEIGHT AND INFLUENCE OF EGG WEIGHT ON BODY WEIGHT OF
LARVAE AND ALEVINS IN RAINBOW TROUT (Onchorynchusmykiss) AT FIRST AND SECOND
SPAWNING
a)
a) Univ. of Ljubljana, Biotechnical fac., Zootechnical Dept.,
Groblje 3, SI-1230 Domžale, Slovenia,
Assoc.Prof., Ph.D., M.Sc.
ABSTRACT
From a certain number of females, eggs were collected during their first and
second spawning. Body mass at spawning (MPlm)
and absolute fecundity (PAbs)
was registered for each female. On the basis of these
data the relative fecundity was calculated (PRel).
For each female 50 eyed eggs as well as 50 offspring at different stages of
growth were individually weighted. Weightings were done 11 days (T1),
6 weeks (T2) and 10 weeks (T3)
after hatching. By such procedure mean weight of the eggs
(MIker) and the mean body mass of
alevins attained at T1, T2 in T3 (MRib1, MRib2
and MRib3) were obtained. The statistical
model of partial regression including PRel
and MIker as independent variables was
used to evaluate the influence of MIker on MRib1,
MRib2 and MRib3. Results indicate
that from heavier eggs heavier larvae are hatched. Nevertheless, the
influence of egg weight on body mass is only short termed. Partial
regression coefficient of MIker on
MRib3is not statistically significant
regardless whether relation between eggs and alevins at first or second
spawning is observed. According to our results it is suggested that eggs
collected at first spawning should not be discarded even they appear to be
too small for production. At age of 10 weeks after hatching, average size of
alevins hatched from small eggs collected at first spawning did not to
essentially differ from average size of alevins hatched from large eggs
collected at second spawning
Agris category
codes: L10
COBISS Code 1.01 Language: English
Effect of
PPARGC-1
gene on
backfat thickness in pigs[1]
a), ,
and
a)Univ. of Ljubljana, Biotechnical fac., Zootechnical Dept.,
Groblje 3, SI-1230 Domžale, Slovenia.
ABSTRACT
PPARGC-1
gene is assumed to be a candidate gene with a major effect on fatness and
meat quality. In this study, frequency of T/A substitution at position 1378
in PPARGC-1 gene in pigs was examined in boars of 4 different breeds.
Frequency of genotypes and alleles were compared between animals with the
thinnest and with the thickest backfat. Differences in genotype frequency
between groups were significant in dam line of Slovenian Landrace (SL11) and
sire line of Large White breed (LW66). Allele A was predominantly present in
animals with thick backfat in SL11 (71.05%), LW66 (58%) and in sire line of
Slovenian Landrace (67.65%). Differences in allele frequency were
significant in SL11. We found a significant effect on phenotypic and
breeding values for backfat in population of Large White breeds, where
homozygotes TT had the thickest backfat, and heterozygotes the thinnest. In
population of Slovenian Landrace breed the thickest backfat had homozygotes AA
and the thinnest homozygotes TT. Similar results were obtained by analysis
of gene effect on breeding values. Inconsistency could be explained by
different background of allele, epistasis and intensity of selection.
[1]This article is
part of a graduation thesis ´Effect of polymorphism T1378A in
PPARGC-1 gene on fattening and growth rate traits in pigs´,
issued by Tina Flisar, supervisor prof. Peter Dovč, Ph.D.
THE
INFLUENCE OF PIG FODDER COMPOSITION ON QUALITY OF DRIED PORK NECK[1]
a),
Tomaž POLAK, Lea GAŠPERLIN, Sergeja VIDAKOVIČ and
Božidar ŽLENDER
a) Univ. of Ljubljana, Biotechnical fac., Zootechnical Dept.,
Groblje 3, SI-1230 Domžale, Slovenia.
ABSTRACT
The aim of the article is to show the influence of diet
composition and sex on sensory and instrumental quality of dried pork neck.
For the research we used 12 hogs and 12 sows. They were separated into 4
groups regarding different food mixture (flaxseed, rapeseed, rapeseed+vit.E
and control mixture). All 24 samples of dried neck were analyzed on fat
content. Sensory analysis of dried necks and instrumental measurement of
colour (CIE -L, -a, -b)
and texture (Kramer shear cell) were performed. The results showed that
different fodder composition had no influence on fattiness of the product,
while sex had a significant influence. Aftertaste was perceived by feeding
with addition of flaxseed and rapeseed. Added vitamin E decreased sensory
characteristics (smell, aroma, texture) and gave lighter colour. The firmer
texture was shown by feeding with rapeseed. Neck from hogs had darker colour
and firmer texture than neck from sows.
[1]
This
article is part of a graduation thesis ´The influence of pig fodder
composition on quality of dried neck´,
issued by Marjeta Furman, supervisor prof. Božidar Žlender, Ph.D.
Agris
category codes: L50
COBISS Code 1.01 Language:
English
MHS status and salivary cortisol concentration in individually housed pigs
[1]
a), and Ivan ŠTUHEC
a)
Univ. of Ljubljana, Biotechnical fac., Zootechnical Dept.,
Groblje 3, SI-1230 Domžale, Slovenia,
Ph.D., B.Sc.
ABSTRACT
Salivary cortisol
was evaluated as stress measure in pigs of two malignant hyperthermia (MH)
genotypes (NN and Nn), housed individually in metabolic cages and in
comfortable large pens with straw. Three replicates were done, each
including 8 German Landrace barrows, four (2 NN, 2 Nn) housed in pens and
four (2 NN, 2 Nn) in metabolic cages. Altogether there were 24 animals
included in the experiment. Saliva samples of all animals were collected
simultaneously every 15 minutes between 8.00 and 11.00 a.m. on days 8, 22
and 36 of the experiment. Pigs in more stressful conditions (metabolic cages)
had higher salivary cortisol values than pigs in pens, indicating that
salivary cortisol might be a suitable indicator of stress in pigs. Higher
salivary cortisol values in NN- in comparison to Nn- pigs indicated stronger
response to stressful conditions in NN-genotype.
[1]The paper
presents a part of the results from the Ph.D. thesis ´The estimation
of the degree of stress in pigs with the evaluation of cortisol
concentration in plasma, urine and saliva´, issued by Nataša Siard,
supervisor prof. Ivan Štuhec, Ph.D.
Agris category codes: Q03
COBISS Code 1.01 Language: English
THE Presence of some
pathogen micro
organisms, yeasts and moulds in cheese samples produced at SMALL DAIRY-PROCESSING
PLANTS
a) and Slavica GOLC
TEGER
a) Univ. of Ljubljana, Biotechnical fac., Zootechnical Dept.,
Groblje 3, SI-1230 Domžale, Slovenia,
Ass.Prof., Ph.D., M.Sc.
ABSTRACT
The presence of pathogenic and some indicator micro organisms
was studied in 40 samples of cheese comprising 14 curd samples, 13 samples
of soft ripened salted or non-salted cheese and 13 samples of semi-hard
cheese manufactured at five small dairy-processing plants. The mean number
of coagulase-positive staphylococci in all tested samples was 2.5 × 104
cfu[1]
g–1, while the number of E. coli
bacteria was 1.4 × 106 cfu g–1. In
20.0% out of 40 samples tested, the number of coagulase-positive
staphylococci exceeded the prescribed regulations, particularly in soft
cheese (12.5%) and curd (7.5%). About 17.5% of samples were contaminated
with E. coli in higher concentrations than national valid regulations
allowed. The number of E. coli was mostly exceeded in soft cheese and
curd in 12.5% and 5.0% of all examined samples, respectively. One sample of
semi hard cheese was contaminated with sulphite-reducing clostridia.
Proteus was detected in 3 samples (7.5%) and L. grayi in 1 (2.5%)
sample. Salmonela and L. monocytogenes were not detected.
According to the valid regulations 9 (22.5%) samples in our investigation
did not reach the adequate microbiological quality. Both, yeasts and moulds
were isolated from 60% of tested cheese samples with average concentrations
of 5.8 × 104cfu g–1and 2.0 × 104cfu
g–1, respectively. The genera Geotrichum
(91.9%), Moniliella (5.4%) and Aspergillus (2.7%) were the
most frequently isolated strains from examined cheese samples. The
Aspergillus strains did not belong to the species A. flavus or
A. parasiticus and did not produce aflatoxins.
