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Production and reproduction performance of Jersey and Fleckvieh × Jersey cows in a pasture-based systemGoni, Sindisile 04 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Genetic selection for high milk production, type and appearance for the last 50 years has suppressed
secondary traits such as reproductive performance, productive life, health and survivability in the pure
milk breeds. The economic importance of these secondary traits in dairy production systems is the
basis for the interest seen in crossbreeding. The problem of growth rate of heifers, cow fertility,
reduced disease resistance and small body frame for beef production in Jerseys can be improved by
crossing Jerseys with dual purpose breeds, such as Fleckviehs which possess a more beef potential.
Against this background, this study aimed at comparing the production and reproduction of Jersey and
Fleckvieh × Jersey cows in a pasture-based system.
Milk recording was done according to standard milk recording procedures. Milk production (milk, fat,
and protein yield) was adjusted to 305 days of lactation and corrected for age at calving. Effects of
breed, parity, month and year were estimated for milk, fat and protein yield as well as fat and protein
percentage using general linear models procedure. The fixed effects identified as having significant
effects on milk, fat and protein yield were breed, parity and year. F×J cows produced significantly more milk than J cows (6141 ± 102 vs. 5398 ± 95 kg milk). Protein and fat yield were significantly
higher in F×J (201 ± 3 and 272 ± 4 kg, respectively) than in J cows (194 ± 2 and 246 ± 3 kg,
respectively). There percentages of fat and protein differed slightly between the two breeds with the
Jersey recording slightly higher percentages (4.61 ± 0.04 and 3.62 ± 0.03 %, respectively) compared
to the F×J cows’ percentages, which were, respectively, 4.47 ± 0.04 and 3.51 ± 0.03 %. It was
concluded that F×J crossbred cows were more productive than purebred J cows probably owing to
heterotic effects.
Heifers were inseminated at 13 months of age and cows 40 days post-calving. Using insemination
records and pregnancy check results, fertility traits were analyzed and compared between the two
breeds, using analysis of variance for continuous records. Conception age was the same for both
breeds resulting in a similar age at first calving. For cows, the interval from calving to first
insemination was significantly shorter (P <0.001) in crossbred cows being 76.7 ± 2.2 days compared
to 82.4 ± 2.5 days for purebreds. A larger proportion (P < 0.001) of 0.70 for crossbred cows was
inseminated within 80 days after calving compared to 0.54 for J cows. Although the absolute number
of days between calving and conception (DO) was lower for F×J cows in comparison to J cows (104.8
± 6.8 vs. 114.8 ± 8.1days, respectively), the difference was not significant. However, the proportion of
F×J cows confirmed pregnant by 100 days in milk was 0.79, which was higher (P < 0.001) than the
0.66 for J cows. Results indicate the potential of improving reproductive performance of J cows
through crossing with dual-purpose breeds. The beef production of purebred J and Fleckvieh x Jersey (F×J) bull calves was compared, where bull
calves were reared similarly for veal, i.e. carcass weight not exceeding 100 kg, or as steers for beef to
21 months of age. In both the veal and steer production systems, the mean birth weight were higher (P
< 0.001) for crossbred in comparison to J calves and steers (33.5 ± 1.2 kg vs. 27.9 ± 1.2 kg for veal)
and (33.4 ± 0.9 kg vs. 26.9 ± 0.9 kg for steers) respectively. The live weight at 6 months of age was
163.5 ± 3.9 kg for J bull calves, which was lower (P < 0.001) than that for F×J bull calves (180.6 ± 4.0 kg). The F×J bull calves had a significantly higher average daily gain (ADG) of 0.82 ± 0.02
kg/day compared to 0.73 ± 0.02 kg/day for J bulls. Marketing age differed (P < 0.001) in the veal
production system with F×J and J bull calves marketed at 7.1 ± 0.1 and 6.3 ± 0.1 months,
respectively. End live weight at 21 months of age was significantly higher (P < 0.001) in F×J bulls
(441.4 ± 14.9 kg) than the 322.6 ± 13.4 kg in J bulls; while ADG differed (P < 0.001) between the two
breeds being 0.64 ± 0.02 and 0.46 ± 0.0 kg/day in F×J and J bull calves, respectively. Crossbred steers
had a significantly higher carcass of 206.5 ± 8.9 kg compared to 157.9 ± 8.6 kg for J steers. Results
indicate the potential of improving beef production characteristics of the J cattle through
crossbreeding. / AFRIKAANSE OPSOMMING: Genetiese seleksie vir hoë melkproduksie, tipe en voorkoms die afgelope 50 jaar het sekondêre
eienskappe soos reproduksie, produktiewe lewe, gesondheid en oorlewing onderdruk in die suiwer
melk rasse. Die ekonomiese belangrikheid van hierdie sekondêre eienskappe in melkproduksie
stelsels is die basis vir kruisteling. Probleme soos groei tempo van verse, koei vrugbaarheid, verlaagde
weerstandbiedenheid teen siektes en klein liggaam raam vir vleisproduksie in Jerseys kan verbeter
word deur die kruising van Jerseys met ' n dubbele doel rasse, soos Fleckviehs wat beskik oor beter
vleis potensiaal. Teen hierdie agtergrond, is hierdie studie daarop gemik om produksie en reproduksie
van Jersey en Fleckvieh x Jersey koeie in 'n weiveld - gebaseerde stelsel te vergelyk.
Melk opname is gedoen volgens standaard melkaantekening prosedures. Melkproduksie (melk-, veten
proteïen opbrengs) was aangepas vir 305 dae van laktasie en gekorrigeer vir kalf ouderdom. ‘n
Algemene lineêre model was gebruik om die effekte van ras, pariteit , maand en jaar op melk-, vet- en
proteïen opbrengs sowel as vet- en proteïen persentasie te bepaal. Die vaste effekte geïdentifiseer met 'n beduidende effek op melk-, vet- en proteïen opbrengs was ras, pariteit en jaar. F × J koeie het
aansienlik meer melk as J koeie (6141 ± 102 teen 5398 ± 95 kg melk) produseer . Vet opbrengs was
aansienlik hoër in F × J koeie as in J koeie (272 ± 4 246 teen ± 3 kg vet). Proteïen opbrengs was ook
aansienlik hoër in F × J koeie as J koeie (201 ± 3 vs 194 ± 2 kg proteïen). Vet en proteïen persentasies
het geneig om effens te verskil met 'n klein effek (4.61 ± 0.04 % vet en 3.62 ± 0.03 % proteïen) vir J
koeie en (4.47 ± 0.04 % vet en 3.51 ± 0.03 % proteïen) vir F × J koeie. Daar is tot die gevolgtrekking
gekom dat F × J gekruisde koeie kan meer produktief wees as suiwer J koeie weens heterotiese
effekte. Verse kunsmatig geïnsemineer was op 13 maande ouderdom en koeie 40 dae na- kalwing aangehou
was. Met behulp van bevrugting en swangerskap rekords, is vrugbaarheid eienskappe ontleed en
vergelyk tussen die twee rasse, met behulp van ontleding van variansie vir deurlopende rekords.
Ouderdom van bevrugting was dieselfde vir beide rasse wat in 'n soortgelyke ouderdomsgroep was by
eerste kalwing. Vir koeie was die interval van kalf tot eerste inseminasie aansienlik korter (P < 0.001)
vir kruisgeteelde koeie wat 76.7 ± 2.2 dae in vergelyking met 82.4 ± 2.5 dae suiwerrasse is. ‘n Groter
proporsie ( P < 0.001) van 0.70 vir gekruisteelde koeie is binne 80 dae na kalwing geïnsemineer in
vergelyking met 0.54 vir J koeie. Alhoewel die absolute aantal dae tussen kalwing en opvatting (DO)
laer was vir F × J koeie in vergelyking met J koeie (104.8 ± 6.8 teen 114.8 ± 8.1dae, onderskeidelik),
is die verskil nie betekenisvol nie. Maar die verhouding van F × J koeie wat swanger bevestig is met
100 dae in melk was 0.79, wat hoër was (P < 0.001) is as die 0.66 vir J koeie. Resultate dui daarop dat
daar potensiaal is reproduktiewe prestasie te verbeter van J koeie deur kruisteling met 'n dubbel- doel
rasse. Die vleisproduksie van suiwer J en Fleckvieh x Jersey (F × J) bulkalwers vergelyk. Die bul kalwers is
soortgelyk grootgemaak vir kalfsvleis, d.w.s karkas gewig mag nie 100 kg oorskry as bulkalwers nie, en as osse vir vleis tot 21 maande oud. In die kalwers- en os produksie stelsels, was die gemiddelde
geboorte gewig hoër (P < 0.001) vir die kruise in vergelyking met J kalwers en osse (33.5 ± 1.2 kg
teen 27.9 ± 1.2 kg vir kalwers) en (33.4 ± 0.9 kg vs . 26.9 ± 0.9 kg vir osse) onderskeidelik . Die
lewendige gewig op 6 maande ouderdom was 163.5 ± 3.9 kg vir J bulkalwers en was hoër (P < 0.001)
vir F × J bulkalwers 180.6 ± 4.0 kg. Die F × J bul kalwers het 'n aansienlik ‘n hoër gemiddelde
daaglikse toename (GDT) van 0.82 ± 0.02 kg/dag in vergelyking met 0.73 ± 0.02 kg/dag vir J bulle.
Bemarkingsouderdom verskil (P < 0.001) in die kalf produksie stelsel met F × J en J bulkalwers
bemark op 7.1 ± 0.1 en 6.3 ± 0.1 maande , onderskeidelik. Finale lewendige gewig van 21 maande
oud was aansienlik hoër 441.4 ± 14.9 kg in F × J bulle as 322.6 ± 13.4 kg in J bulle , terwyl GDT hoër
was (P < 0.001), met 0.64 ± 0.02 kg/dag en 0.46 ± 0.0 kg/dag in F × J en J bulkalwers, onderskeidelik.
Gekruisde osse het 'n aansienlik hoër karkasgewig 206.5 ± 8.9 kg in vergelyking met 157.9 ± 8.6 kg
van J osse. Resultate dui daarop dat daar potensiaal is om die beesvleis produksie-eienskappe van die
J beeste te verbeter d.m.v. kruisteling.
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Estimation of genetic parameters for fertility traits and the effect of milk production on reproduction performance in South African Holstein cowsPotgieter, Johannes Phillipus 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Profitable milk production and genetic improvement in dairy herds are largely dependant on fertile
cows capable of calving down on an annual basis. Several studies indicate declines in the
reproductive performance of Holstein cows over the last 30 years. Calving interval (CI) and services
per conception (SPC) are being used by dairy farmers as indicators of the reproductive performance
of dairy cows. However, using these traits as cow fertility indicators is problematic as CI is dependent
on subsequent calving dates while SPC is strongly linked to inseminator proficiency. The aim of the
study is therefore, firstly, to describe alternative fertility traits derived from insemination and calving
dates and pregnancy check results. The effects of some non-genetic factors on these traits are
discussed. Means±sd for interval traits from calving to first insemination (CFS) and the interval from
calving to conception (DO) were respectively 77±30 and 134±74 days while the number of services
per conception (SPC) averaged 2.55±1.79. The percentage of first servics occurring within 80 days
post-partum (FS80d) and the proportion of cows being confirmed pregnant within 100 (PD100d) and
200 days post-partum (PD200d) were 0.64±0.48, 0.36±0.48 and 0.71±0.45, respectively. Although
fertility traits were affected significantly by lactation number, calving year and month, herds
(managers) had the largest effect.
Fertility is a complex trait, however, the challenge is finding traits that best describe this trait. Genetic
parameters for these traits could give an indication of the response to selection in dairy herds. In the
second part of this study, genetic parameters and correlations between fertility traits, sourced from
standard reproduction management data bases, are analysed for Holstein cows using bivariate linearlinear
and linear-threshold animal models. Insemination events (n = 69 181) from 26 645 lactations of
9 046 Holstein cows from 14 herds, calving down during the period from 1991 to 2007, were
available. The outcome of each AI event was known. Insemination records were linked to the calving
date of each cow, lactation number as well as dam and sire identification. Fertility traits indicating the
ability of cows to show heat early in the breeding period, and to become pregnant, were derived. Data were analysed using bivariate linear-linear and linear-threshold animal models with fixed effects being
herd (14 levels), year (17 levels), season (4 levels) and lactation number (6 levels). The model
included the random effects of animal and animal permanent environment (PE). Heritability estimates
ranged from 0.04±0.01 to 0.10±0.02 for FS80d, from 0.07±0.01 to 0.08±0.02 for PD100d and from
0.06±0.04 to 0.08±0.02 for PD200d depending on the two-trait combination. Although heritability
estimates of most fertility traits were below 0.10, they were in close agreement with results published
by other researchers using linear models. Genetic correlations between different fertility parameters
analyzed in this study indicated that it is unlikely that a single characteristic would serve well for
selection purposes; instead, combining different traits could be used in selection programmes to
improve fertility. Further research in constructing an optimal fertility index is warranted.
In the third part of this study, genetic parameters for South African Holstein cows for fertility and
production traits were estimated from 2415 lactation records. Two-trait analysis of fertility and milk
yield was investigated as a method to estimate fertility breeding values when culling, or selection
based on milk yield in early lactation, determines presence or absence of fertility observations in later
lactations. Fertility traits were days from calving to first service (CFS), days from calving to conception
(DO), percentage cows inseminated within 80d post-partum (FS80d), number of service per
conception (SPC), and the binary traits percentage of cows pregnant within 100d and 200d postpartum
(PD100d, Pd200d). Milk production traits were 300 day milk, fat and protein yield. For fertility
traits, range of estimates of heritability (h2) was 0.006 to 0.08 for linear traits and 0.05 to 0.12 for
binary traits. The range for permanent environmental variance (c2) was 0.016 to 0.032. In this study
genetic correlations of fertility with milk production traits were unfavourable ranging between −0.93 to 0.76. / AFRIKAANSE OPSOMMING: Winsgewende melkproduksie en genetiese verbetering in melkkuddes hang grootliks af van vrugbare
koeie wat op ‘n jaarlikse basis kalf. Verskeie studies toon dat die reproduksievermoë van
Holsteinkoeie oor die afgelope 30 jaar afgeneem het. Melkboere gebruik tussenkalfperiode (TKP) en
aantal inseminasies per konsepsie (KIPK) as aanduidings van die reproduksievermoë van melkkoeie.
Dit is egter moeilik om hierdie eienskappe as vrugbaarheidseienskappe vir melkkoeie te gebruik
omdat TKP afhanklik is van opeenvolgende kalfdatums terwyl KIPK baie sterk gekoppel is aan die
inseminasievermoë van die insemineerders. In die eerste gedeelte van die studie word alternatiewe
vrugbaarheidseienskappe, wat afgelei is van inseminasie- en kalfdatums en die uitslag van
dragtigheidsondersoeke, beskryf. Die invloed van ‘n aantal nie-genetiese faktore op dié eienskappe
word ook bespreek. Gemiddeldes±standaard afwykings vir die periode vanaf kalwing tot eerste
inseminasie (CFS), die periode van kalwing tot konsepsie (DO) was 77±30 en 134±74 dae
onderskeidelik, terwyl die aantal inseminasies per konsepsie (SPC) 2.55±1.79 was. Die persentasie
eerste inseminasies wat binne 80 dae na kalwing (FS80d), en die persentasie koeie wat dragtig
bevestig is binne 100 (PD100d) en 200 dae na kalwing (PD200d) was 0.64±0.48, 0.36±0.48 en
0.71±0.45, onderskeidelik. Hoewel vrugbaarheidseienskappe betekenisvol beïnvloed is deur
laktasienommer, jaar en seisoen van kalwing, het kuddes (bestuurders) die grootste effek op
eienskappe gehad.
Vrugbaarheid is ‘n ingewikkelde eienskap en die uitdaging is om eienskappe te vind wat dit die beste
beskryf. Genetiese parameters vir eienskappe wat oorweeg word sal ‘n aanduiding gee van die
seleksieresponse in melkkuddes. In die tweede gedeelte van die studie is genetiese parameters van
vrugbaarheidseienskappe en korrelasies tussen dié eienskappe beraam. Eienskappe is bekom vanaf
reproduksiebestuursprogramme wat in melkkuddes gebruik word. Al die inseminasierekords (n =
69 181) van 26 645 laktasies van 9 046 Holsteinkoeie van 14 melkkuddes wat tussen 1991 en 2007 gekalf het, was beskikbaar. Die uitslag van elke inseminasie was bekend. Inseminasierekords is met
die kalfdatum, laktasienommer, identifkasienommers van die moeder en vader van elke koei,
gekoppel. Vrugbaarheidseienskappe wat die vermoë van koeie aandui om vroeg na kalwing op hitte
te kom en beset te raak, is verkry. Die data is ontleed deur gebruik te maak van twee-eienskap liniêreliniêr-
en liniêr-drempel-diere modelle met vaste effekte kudde (14 vlakke), jaar (17 vlakke), siesoen (4
vlakke) en laktasienommer (6 vlakke). Die modelle het die ewekansige effekte van dier- en dierpermananente
omgewingseffkte (PE) ingesluit. Genetiese, diere PE en residuele korrelasies is
vervolgens beraam. Oorerflikhede varieer vanaf 0.04±0.01 tot 0.10±0.02 vir FS80d, vanaf 0.07±0.01
tot 0.08±0.02 vir PD100d en vanaf 0.06±0.04 tot 0.08±0.02 vir PD200d, afhangende van die tweeeienskap
kombinasie. Ten spyte daarvan dat die oorerflikhede van die meeste vrugbaarseienskappe
laer as 0.10 is, is die resultate in ooreenstemming met ander navorsers wat liniëre modelle gebruik
het. Genetiese korrelasies tussen verskillende vrugbaarheidseienskappe toon dat daar nie enkel
beste eienskap is wat vir seleksiedoeleindes gebruik kan word nie. Dit sou waarskynlik beter wees om
verskillende eienskappe te kombineer om die vrugbaarheid in melkkoeie te verbeter. Verdere
navorsing is nodig om ‘n optimale vrugbaarheidseienskap te ontwikkel.
Dit is belangrik dat die verband tussen reproduksie en melkproduksie vir melkkoeie bepaal word. In
die derde gedeelte van die studie is genetiese parameters vir vrugbaarheid- en melkproduksieeienskappe
vir Suid Afrikaanse Holsteinkoeie beraam. ‘n Totaal van 2415 laktasierekords was
beskikbaar. Vrugbaarheid en melkproduksie is volgens ‘n twee-eienskap analise ontleed as ‘n metode
om teelwaardes vir vrugbaarheid te bepaal in gevalle waar die uitskot of seleksie gebaseer op
melkproduksie in vroeglaktasie die teenwoordigheid of afwesigheid van vrugbaarheidseienskappe in
latere laktasies bepaal. Vrugbaarheidseienskappe was die periode (aantal dae) tussen kalfdatum en
eerste inseminasie (CFS), die aantal dae van kalf tot konsepsie (DO), die persentasie koeie wat by 80
dae na kalf vir die eerste keer geïnsemineer was (FS80d), die aantal inseminasies per konsepsie
(SPC), en binêre eienskappe van die persentasie koeie wat by 100 dae en 200 dae na kalf beset was
(PD100d en PD200d). Melkproduksie-eienskappe was 300-dae melk., vet- en proteïnproduksie. Vir
vrugbaarheidseienskappe het die oorerflikheidswaardes (h2) vanaf 0.006 tot 0.08 vir liniêre
eienskappe gevarieer en tussen 0.05 tot 0.12 vir binêre eienskappe. Die permanente
omgewingsvariansie (c2) het tussen 0.016 tot 0.032 gevarieer. In hierdie studie was die genetiese
korrelasies tussen vrugbaarheidseienskappe en melkproduksie-eienskappe ongunstig en het dit
tussen −0.93 tot 0.76 gevarieer.
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SOSTENIBILITA' NUTRIZIONALE ED ECONOMICA: SVILUPPO DI INDICI AGGREGATI PER MIGLIORARE LA COMPETITIVITA' IN ALLEVAMENTI DI VACCHE DA LATTE / Nutritional and economic sustainability: development of aggregate indices to improve competitiveness in dairy cow herdsVALSECCHI, CLAUDIO 27 April 2021 (has links)
Gli allevamenti di vacche da latte puntano alla massimizzazione della produzione di latte credendo di migliorare così il profitto attraverso l’effetto di diluizione dei costi di mantenimento. Diventa però importante avere sotto controllo i costi di produzione, ma soprattutto la reale efficienza aziendale.
Il principale obiettivo di questo lavoro di ricerca è quello di trovare un sistema di monitoraggio dell’efficienza aziendale, sia economica che nutrizionale, utile per i tecnici che visitano le aziende zootecniche di vacche da latte per poter supportare le scelte imprenditoriali dell’allevatore.
Sono stati misurati indici tecnici ed economici in 90 allevamenti di vacche da latte per valutare l'efficienza nutrizionale ed economica degli allevamenti. Un approccio multivariato è stato utilizzato per aggregare gli indicatori parziali in nuove strutture latenti.
Un secondo obiettivo è stato quello di predire, attraverso le caratteristiche aziendali ed altre informazioni relative alla gestione dell’azienda, gli indici aggregati di efficienza aziendale ricavati, ovvero: efficienza economica, efficienza energetica e punto di pareggio. Ottantanove aziende di vacche da latte sono state visitate e intervistate per raccogliere informazioni sulla consistenza della mandria, la produzione e la qualità del latte, le prestazioni riproduttive, il benessere delle vacche allevate, la formulazione della dieta e i costi di alimentazione.
Infine sono state caratterizzare le diverse strategie alimentari adottate nelle aziende visitate. Sono state raccolte informazioni sulle performances della mandria, sui costi di alimentazione e sulle differenti razioni formulate. Sono state caratterizzate la composizione chimica delle diete, il profilo fermentativo delle diete e la produzione di metano, l'efficienza alimentare della mandria, la produzione e la qualità del latte e il profilo fermentativo fecale. / Dairy cow farms aim to maximize milk production believing that this will improve profit through the dilution effect of maintenance costs. However, it becomes important to have under control the feed production costs, but above all the effective business efficiency of whole herd.
The main objective of this research work is to find a monitoring system of farm efficiency, both economic and nutritional, useful for technicians who visit dairy farms in order to support the entrepreneurial choices of the farmer.
Technical and economic indices were measured on 90 dairy cow farms to assess the nutritional and economic efficiency of the farms. A multivariate approach was used to aggregate partial indicators into new latent structures.
A second objective was to predict, through farm characteristics and other farm management information, the aggregate farm efficiency indices derived: economic efficiency, energy efficiency, and break-even point. Eighty-nine dairy cow farms were visited and interviewed to collect information on herd size, milk production and quality, reproductive performance, cow welfare, diet formulation and feeding costs.
Finally, the different feeding strategies adopted on visited farms were characterized. Information was collected on herd performance, feeding costs and different formulated rations. The chemical composition of the diets, the fermentative profile of the diets and methane production, feeding efficiency of the herd, milk production and quality and fecal fermentative profile were characterized.
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