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Effects of sex and Compudose® implantation on porcine muscle histochemistryHighfill, Gregory Alvin. January 1984 (has links)
Call number: LD2668 .T4 1984 H537 / Master of Science
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Effect of methionine addition to weanling pig dietsOng, Tze-Chow. January 1984 (has links)
Call number: LD2668 .T4 1984 O53 / Master of Science
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Effects of increased slaughter weight of pigs on pork productionPieterse, Elsje 04 1900 (has links)
Thesis (PhDAgric)--Stellenbosch University, 2006. / ENGLISH ABSTRACT: The South African pork industry is characterised by low slaughter weights
when compared to the rest of the world. This inevitably leads to a smaller
number of kilograms produced per unit fixed cost and subsequently the
efficiency of production is reduced. A study was conducted with 189 pigs
representing three sex types (boar, gilt and castrate) and five commercial
genotypes. Pigs entered into the trial at an age of 10 weeks and an average
live weight of 27.5±2.5kg. Treatments were according to slaughter weight
ranging between 62 and 146kg. Production and carcass characteristics, meat
quality and processing characteristics and sensory attributes were assessed.
Production characteristics assessed included live weight gains, intake, P2
backfat thickness and feed conversion ratio. Main observed effects were
associated with slaughter weight and its interaction with sex type. Rates of
change in parameters measured were described. Growth and feed
conversion ratio were described using linear models while cumulative feed
intake was described using 2nd order polynomials. Carcass characteristics
assessed included carcass weight, dressing percentage, carcass length, ham
length, ham circumference, chest depth, backfat thickness measurements,
muscle depth, eye muscle area, subcutaneous fat area, intramuscular fat area
as well as ratios of eye muscle to subcutaneous and intramuscular fat area.
The main statistical differences observed were for slaughter weight.
Significant sex type differences were observed for dressing percentage and
some fat and muscle depth measurements. Meat quality characteristics
assessed included colour measurements, tenderness, drip loss and water
holding capacity. Main differences observed were for slaughter weight.
Carcass yields were assessed in terms of absolute and percentage yields of
commercial cuts as well as yield of processable lean meat. In terms of the
absolute and percentage yields of the commercial cuts, the main statistical
differences observed were for slaughter weight. Changes in cut yield with increased slaughter weight are described using regression analysis. In terms
of yields obtained for processable lean meat, the main statistical differences
observed were for slaughter weight.
Sex type differences were only observed for percentage belly and topside
processable lean meat and percentage brine uptake of belly bacon, whole
gammon ham and topside gammon. Genotypic differences were observed for
percentage yield of processable lean meat of the neck and whole gammon
and percentage fresh to smoke losses of back bacon and whole gammon
ham. Sensory attributes were assessed using gammon ham, belly bacon and
fresh loin. Observed slaughter weight differences were inconsistent and did
not appear to change with an increase in slaughter weight. Once meat was
processed, most sensory differences were no longer observed. Increased
slaughter weight generally led to increased juiciness and decreased
tenderness.
It is therefore concluded that the current South African pig genotypes have the
ability to maintain high growth rates for a much longer time and therefore can
be slaughtered at a higher weight without detrimental effect on production
efficiency, carcass and meat quality characteristics, yields of commercial and
processable lean meat, processing characteristics and ultimately sensory
characteristics of the meat produced. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse varkbedryf word gekenmerk deur relatiewe lae
slagmassas in vergelyking met die res van die wêreld. Dit lei onvermydelik tot
‘n kleiner aantal kilogramme vleis geproduseer per eenheid vaste koste. ’n
Studie is gevolglik gedoen met die doel om die tempo’s van verandering van
sekere produksie-, karkas-, vleis- en proseseringseienskappe te kwantifiseer
ten einde die optimale slagmassa te bepaal wat vir alle rolspelers in die bedryf
tot voordeel sal wees. Die studie is gedoen met 189 diere wat vyf
kommersiële genotipes en drie geslagstipes (beer, sog en kastraat)
verteenwoordig het. Varke is op ’n ouderdom van 10 weke met ’n gemiddelde
lewende massa van 27.5±2.5kg in die proef opgeneem. Behandelings was
volgens slagmassa en het gevariëer van 62 tot 146kg. Produksieparameters
en karkas-, vleiskwaliteits-, en proseseringseienskappe sowel as sensoriese
eienskappe, is ëvalueer.
Produksieeienskappe wat ëvalueer is sluit in: groei, inname, P2 rugvetdikte en
voeromset-verhoudings. Hoofeffekte wat waargeneem is, was vir slagmassa
en interaksies van slagmassa met geslag. Tempo van verandering in die
parameters gemeet, is beskryf. Groei en voeromsette is beskryf deur die
passing van ‘n linieêre model terwyl kumulatiewe voerinname beskryf is deur
‘n 2de orde polinoom. Karkaseienskappe wat ëvalueer is, sluit in:
karkasmassa, uitslagpersentasie, karkaslengte, hamlengte, hamomtrek,
borsdiepte, rugvetdikte, spierdiepte, oogspieroppervlak, onderhuidse vet-,
binnespierse vetoppervlak en verhoudings van oogspier- tot-vetoppervlakke.
Die hoof statistiese effekte wat waargeneem is, was vir slagmassa.
Betekenisvolle geslagsverskille is waargeneem vir uitslagpersentasie en
sommige, vet- en spierdieptemetings. Genotipiese verskille is waargeneem
vir sommige vetmetings. Vleiskwaliteiteienskappe wat beoordeel is, het kleur,
drupverlies, waterbindingsvermoë en sagtheid ingesluit. Hoofeffekte
waargeneem was vir slagmassa. Karkasopbrengste is ëvalueer in terme van absolute en persentasie opbrengste van kommersiële snitte sowel as
prosesseerbare maer vleis. In terme van absolute en persentasie opbrengste
van kommersiële snitte, was meeste van die variasie beskryf deur slagmassa.
Tempo van verandering in die persentasie opbrengste van die snitte word
beskryf. In terme van opbrengste vir proseseerbare maer vleis is die hoof
statistiese verskille waargeneem vir slagmassa. Geslagverskille is
waargeneem vir persentasie streepspek en binneboud maer vleis opbrengs
vir prosesering en persentasie pekelopname van streepspek, heel varkboud
ham en binneboud ham. Genotipe verskille is waargeneem vir persentasie
opbrengs van maer vleis vir prosesering van die nek en heelboud en
persentasie vars-tot-klaar-gerook verliese van rugspek en heelboud hamme.
Sensoriese eienskappe is ëvalueer vir twee geprosesseerde en een vars snit.
Slagmassa-effekte was nie konstant nie en parameters het klaarblyklik nie
verander soos slagmassa verander het nie. Sodra vleis geprosesseer is, het
die meeste sensoriese verskille verdwyn. Beide sappigheid en taaiheid het
toegeneem met ‘n toename in slagmassa.
Dit kan dus aanvaar word dat, gegewe die huidige Suid Afrikaanse genotipes,
dit moontlik is om swaarder karkasse te produseer sonder noemenswaardige
nadelige effekte op karkas-, vleis-, opbrengste-, prosesering- en sensoriese
eienskappe van varkvleis.
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Developmental physiology of the intestine in neonatal pigs: effects of milk and milk-borne growthfactorsWang, Tian, 王恬 January 1998 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy
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Productivity of indigenous pigs in communal production systems of Sekhukhune District in Limpopo ProvinceSoana, Legoai Winter January 2013 (has links)
Thesis (M.A. (Agricultural Management)) -- University of Limpopo, 2013 / A study was conducted to determine environmental and socio-economic factors affecting pig productivity in communal areas. A questionnaire was administered to collect data on production environment and socio-economic variables underlying productivity in Sekhukhune District. Production environment included explanatory sex of the piglet, season of birth, feed type, housing type, municipality, herd size, health management and disease prevalence, while socio-economic variables included household size and gender of head of household, age, level of education and employment status. A total of 112 farmers were interviewed from 25 villages. Data on productivity were collected using production record sheets. Performance parameters in the production sheets included litter size, litter weight, individual birth weight, live weight and mortality. Monitoring was done from birth date to subsequent farrowing date at the farmers’ backyard. One farrowing sow per producer was used and a total of 605 piglets were monitored in the municipalities.
A total of 1468 indigenous pigs were kept for breeding with 104 castrated males occupying less space in the production system within the district. Feeding was characterized by kitchen wastes or garbage at total of 78 farmers, 22 feeding garbage and grains, and only 12 farmers feeding concentrate. There was measles prevalence in the production system with a total of 41 farmers treating the suspected pigs; the larger number (71) however, did not treat pigs. Health did not affect (P>0.05) litter size and birth weight. Birth weight was affected (P>0.05) by disease prevalence, herd size, household head sex, age and education, and family size. Mean litter size was 4.38 piglets at birth, mean litter weights of 5.78 kg, mean birth weight of 1.32, and mean mortality at 2.31 piglets. Season, feed, municipality, diseases, herd size, the age, education and employment of household head affected pre-weaning mortality (P<0.05).
v
There is statistical evidence (P<0.05) that there were associations between litter size, litter weight, birth weight and mortality and the feed, municipality, diseases, herd size, the age, education and employment of household head respectively. There were deficiencies in the entire production system with regards to pig management practices, feeding practices, housing of pigs, breeding systems, herd composition and size and the general practices in the keeping of the pig herds by majority of pig producers. These deficiencies call for introduction of sound pig management plans in communal areas which should include keeping pigs indoor to account for the healthy herd, proper feeding and sound breeding plans.
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Microsatellite-based characterization of Southern African domestic pig (Sus scrofa domestica) breedsSwart, Hannelize January 2010 (has links)
Thesis (M.Sc. (Zoology)) --University of Limpopo, 2010 / Refer to document
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Antagonistic activity of probiotic bacteria based on bacterial diversity in the porcine gutDixit, Sameer M., University of Western Sydney, Centre for Advanced Food Research January 2004 (has links)
Diversity analysis of Escherichia coli have routinely utilised isolates obtained by culture of faeces on MacConkey selective media, under the assumption that the diversity identified in faecal isolates are representative of similar diversity in E. coli in the gastrointestinal tract (GIT). This study has addressed this important issue by specifically isolating E. coli from different regions of the gut in pigs and subjecting them to enzymatic multilocus enzyme electrophoresis (MLEE) and molecular virulence factor (VF) analysis to ascertain whether E. coli populations inhabiting different regions of the gut are different from each other. Combination of these results showed that on average, E. coli strains isolated from the upper GIT region (small intestine) of the pig are distinctly different from the E. coli strains isolated from the lower GIT region (large intestine). An important aspect of the finding that faecal E. coli are not truly representative of the diversity in the GIT is the mechanism used by specific clonotypes that have adapted to different geographical habitats to survive challenge from incoming strains. / Doctor of Philosophy (PhD)
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Transgenic livestock: studies in improved efficiency of production and gene regulationFrench, Andrew James. January 1991 (has links) (PDF)
Includes list of papers and publications by the author Includes bibliographical references (leaves 198-231) Reports on studies aimed at increasing the efficiency of livestock transgenesis programs. Overall the experiments provide an improved basis for understanding the application of animal biotechnology to the pig.
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The porcine gastrointestinal epithelium : metabolism of glutamine for energy production /Madej, Malgorzata. January 2001 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2001. / Includes bibliographical references.
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Studies on the prevalence of trichinella spiralis infection in pigs imported into Hong Kong /Chan, Shiu-wan. January 1986 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1987.
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