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Master of Science

Lactation records of cows born since 1964 were used to compute Cow Indexes (CI) for 581,519 Holsteins and 352,758 Jerseys. CI were used to predict Modified Contemporary Deviations (MCD) of daughters at three levels each of herd mean (µ) and standard deviation (σ), and regressions were compared to expected values. For Holsteins, regressions were greater than expected in herds with average µ or high σ, suggesting that heritability (h²) should be higher for cows in those herds. Heritability estimates agreed with observed regressions for herd σ (h2 of .178, .193, and . 206 as herd σ increased) but not for herd µ (h² of . 222, .163, and .206). For Jerseys, regression results indicated that h² should increase with herd µ, but there was no trend for herd σ. Heritability estimates agreed with the observed regressions for µ (h² of .246, .291, and .331) but not for σ, as h² increased substantially ( .254, .293, and .371) as herd σ increased. Eight adjustments were made for CI: two varied h² to adjust for genetic effects, two adjusted MCD for environmental effects, and four were combinations of these. For Holsteins, regressions of daughter MCD on darn CI were greater than expected for all CI, but regressions of son MCD on darn CI were less than expected. Rankings of CI, based on R² , differed considerably for the three groups examined (all daughters, daughters of elite cows, and sons). For Jerseys, CI of elite darns predicted offspring MCD as expected, but for several CI, regressions for all daughters were less than expected. There were smaller differences in rankings of CI than for Holsteins. Under the assumption that large true breed differences are unlikely, the best CI for both breeds had MCD standardized to a common variance, with h² of .20. This was nearly optimal for Jersey groups, although less than optimal for Holsteins. This CI adjusted for environmental effects of herd a, ignoring differences in genetic variation. It decreased differences among CI for cows in high variance herds, and increased differences in low variance herds. / Ph. D.

Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The dry matter (DM) production and chemical composition of whole crop faba beans (Vicia faba) and oats (Avena sativa) were determined according to fresh material harvested at weekly intervals. From 75 to 166 days after planting whole plants of faba beans and oats were harvested at a height of ca. 10 cm above the ground on five randomly selected areas of 0.25 m² each. The freshly harvested material was weighed “as is” and ovendried to determine the DM content of each sample. The fresh and DM forage production per hectare was then calculated. The crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), nitrogen free extract (NFE), fat (EE), calcium (Ca) and phosphorus (P) contents were determined according to standard laboratory techniques. The change in chemical composition of fresh whole crop material was regressed on days after planting using simple linear regressions. The fresh and DM production of whole crop faba beans and oats increased with advancing growth stage. During the 2002 production year fresh yield production of both whole crop faba beans and oats peaked at 131 days (44.7±6.9 and 28.4±7.1 ton/ha respectively). DM yield peaked at 159 and 152 days for whole crop faba beans and oats being 9.4±1.3 and 8.8±0.7 tons DM/ha respectively. The chemical composition of both forage crops decreased with advancing growth stage. The CP content of whole crop faba beans decreased (P<0.05) from 25.3% at 82 days after planting to 18.4 % at 166 days after planting in the 2002 production year, while during the 2003 production year the CP content of whole crop faba beans decreased (P<0.05) from 28.2 to 19.5 % from 75 to 159 days after planting. During 2002 the CF % of faba beans increased from 20.2 to 22.6%, while during 2003 CF % similarly increased from 21.8 to 26.5%. The CF % for oats during 2003 increased from 25.6 to 36.9%. During the same time the EE, Ca and P contents also decreased (P<0.05), while the NDF, CF and ADF contents increased (P<0.05). Two milk production studies were conducted to compare the feed intake, milk yield and milk composition of Holstein cows receiving either whole plant faba bean silage or oats as a hay or silage. Faba bean (Vicia faba) silage (FBS) was compared to that of cows receiving either oat (Avena sativa) hay (OH) or oat silage (OS) and in a 50:50 combination with FBS. Faba beans (cv. Ascot) and oats (cv. Sederberg) were planted on a Glenrosa soil. Whole crop faba beans were ensiled 145 days after planting in an above ground concrete bunker using a commercial bacterial inoculant after being wilted for one day. In the first experiment, total mixed rations (TMR) containing FBS, OH or a 50:50 mixture of FBS and OH as forage, together with a concentrate, were fed to three groups of seven lactating Holstein cows each. The experiment was conducted according to a randomized block design. Cows were on average 112±44 days post calving producing 24.0±6.2 kg milk/day. Milk production parameters of cows receiving diets containing different forages were compared by analysis of variance. The DM intake and milk yield of cows receiving TMR’s containing FBS, OH or a mixture of 50:50 FBS and OH as forages did not differ (P>0.05), milk yields being 18.9±1.9, 20.6±1.3 and 20.5±1.4 kg/cow/day respectively. With the exception of MUN, milk composition parameters did not differ among treatments (P>0.10). Cows fed OH as roughage source had a higher (P=0.06) MUN level in the milk. Results from this study indicate that FBS could effectively replace OH in lactating dairy cow diets. In the second experiment, total mixed rations (TMR) containing FBS, oat silage (OS) or a 50:50 mixture of FBS and OS as forages, together with a concentrate, were fed to six Holstein cows according to a double 3 x 3 Latin Square cross-over experimental design. Each cow received 13 kg DM either FBS, OS or a 50:50 mixture of FBS and OS were fed as forages, together with three different concentrates at nine kg “as is” each, to each cow. Cows were on average 108±30 days post calving producing 22.0±2.0 kg milk/day. DM intake, body weight, milk yield and milk composition parameters of cows receiving diets containing different forages were compared statistically. The DM intake and body weight of cows receiving TMR’s containing FBS, OH or a mixture of 50:50 FBS and OS as forages did not differ (P>0.10), although body weight changes differed significantly (P<0.10), i.e. 4.0±3.2, 8.8±3.2 and -6.0±3.2 kg respectively. The milk yield of cows receiving TMR’s containing FBS, OS or a mixture of 50:50 FBS and OS as forages did not differ (P>0.10), milk yields being 22.8±0.4, 21.4±0.4 and 21.9±0.4 kg/cow/day respectively. Of the milk composition parameters, the milk CP(%) of cows fed TMR’s containing FBS differed (P<0.05) from the cows fed the 50:50 mixture of FBS and OS, as well as cows fed the OS, being 2.82±0.02, 2.93±0.02 and 2.96±0.02% respectively. Results from this study indicate that FBS could effectively replace OS in lactating dairy cow diets. The South African database on in situ protein and fiber degradability values for whole crop faba beans and oats is limited. The chemical composition of whole crop faba beans and oats constantly change as plants mature. For optimal stage of ensiling and feed formulation it would be useful to have CP, NDF and ADF degradability values available for whole crop faba beans and oats harvested at different growth stages. The objective of this study was to determine the ruminal nutrient degradabilities of whole crop faba beans (Vicia faba) and oats (Avena sativa). Whole crop faba beans and oats were cut at weekly intervals from 75 to 159 days after planting. Effective DM, CP, NDF and ADF degradability values of faba beans and oats harvested at 117, 131, 145 and 159 days after planting were determined by using the in situ nylon bag technique. Three non-lactating Holstein cows fitted with ruminal fistulae were used. Plant material put into Dacron bags was incubated in the rumen for 4, 8, 12, 24, 48, 72 and 96 hours. The degradability of DM, CP, NDF and ADF fractions of whole plant faba beans and oats in four different growth stages (117, 131, 145 and 159 days from planting) did not differ (P<0.05) among cows. The degradability of different fractions for both roughages were affected (P<0.05) by growth stage and incubation hours. DM, CP, NDF and ADF disappearance of whole crop faba beans and oats at 117 and 159 days after planting differed (P<0.05) at 4, 8, 12, 24, 48, 72 and 96 hours of incubation time. The DM, CP, NDF and ADF disappearance values were fitted to the non-linear model p = a + b (1- e-ct). The effective degradabilities (P) could be calculated using a fractional outflow rate of k = 0.05. For whole crop faba beans, parameter b (potentially degradable fraction) and parameter c (the rate at which b is degraded) all differed different forages were compared by analysis of variance. The DM intake and milk yield of cows receiving TMR’s containing FBS, OH or a mixture of 50:50 FBS and OH as forages did not differ (P>0.05), milk yields being 18.9±1.9, 20.6±1.3 and 20.5±1.4 kg/cow/day respectively. With the exception of MUN, milk composition parameters did not differ among treatments (P>0.10). Cows fed OH as roughage source had a higher (P=0.06) MUN level in the milk. Results from this study indicate that FBS could effectively replace OH in lactating dairy cow diets. In the second experiment, total mixed rations (TMR) containing FBS, oat silage (OS) or a 50:50 mixture of FBS and OS as forages, together with a concentrate, were fed to six Holstein cows according to a double 3 x 3 Latin Square cross-over experimental design. Each cow received 13 kg DM either FBS, OS or a 50:50 mixture of FBS and OS were fed as forages, together with three different concentrates at nine kg “as is” each, to each cow. Cows were on average 108±30 days post calving producing 22.0±2.0 kg milk/day. DM intake, body weight, milk yield and milk composition parameters of cows receiving diets containing different forages were compared statistically. The DM intake and body weight of cows receiving TMR’s containing FBS, OH or a mixture of 50:50 FBS and OS as forages did not differ (P>0.10), although body weight changes differed significantly (P<0.10), i.e. 4.0±3.2, 8.8±3.2 and -6.0±3.2 kg respectively. The milk yield of cows receiving TMR’s containing FBS, OS or a mixture of 50:50 FBS and OS as forages did not differ (P>0.10), milk yields being 22.8±0.4, 21.4±0.4 and 21.9±0.4 kg/cow/day respectively. Of the milk composition parameters, the milk CP(%) of cows fed TMR’s containing FBS differed (P<0.05) from the cows fed the 50:50 mixture of FBS and OS, as well as cows fed the OS, being 2.82±0.02, 2.93±0.02 and 2.96±0.02% respectively. Results from this study indicate that FBS could effectively replace OS in lactating dairy cow diets. The South African database on in situ protein and fiber degradability values for whole crop faba beans and oats is limited. The chemical composition of whole crop faba beans and oats constantly change as plants mature. For optimal stage of ensiling and feed formulation it would be useful to have CP, NDF and ADF degradability values available for whole crop faba beans and oats harvested at different growth stages. The objective of this study was to determine the ruminal nutrient degradabilities of whole crop faba beans (Vicia faba) and oats (Avena sativa). Whole crop faba beans and oats were cut at weekly intervals from 75 to 159 days after planting. Effective DM, CP, NDF and ADF degradability values of faba beans and oats harvested at 117, 131, 145 and 159 days after planting were determined by using the in situ nylon bag technique. Three non-lactating Holstein cows fitted with ruminal fistulae were used. Plant material put into Dacron bags was incubated in the rumen for 4, 8, 12, 24, 48, 72 and 96 hours. The degradability of DM, CP, NDF and ADF fractions of whole plant faba beans and oats in four different growth stages (117, 131, 145 and 159 days from planting) did not differ (P<0.05) among cows. The degradability of different fractions for both roughages were affected (P<0.05) by growth stage and incubation hours. DM, CP, NDF and ADF disappearance of whole crop faba beans and oats at 117 and 159 days after planting differed (P<0.05) at 4, 8, 12, 24, 48, 72 and 96 hours of incubation time. The DM, CP, NDF and ADF disappearance values were fitted to the non-linear model p = a + b (1- e-ct). The effective degradabilities (P) could be calculated using a fractional outflow rate of k = 0.05. For whole crop faba beans, parameter b (potentially degradable fraction) and parameter c (the rate at which b is degraded) all differed v significantly (P<0.05) between four different growth stages (117, 131, 145 and 159 days from planting) of plant maturity for CP, NDF and ADF. In oats, parameter b and parameter c did not differ (P>0.05) between the four different growth stages (117, 131, 145 and 159 days from planting) of plant maturity. Results from this study could make a valuable contribution towards the South African databases on faba bean and oats nutrient values and can be used in dynamic feed formulation. Faba beans cut as fresh crop or silage may in the foreseeable future play an increasingly larger role in the feeding of dairy cattle in the Winter Rainfall Region of South Africa. As in the case of lupin silage, though with much higher protein content, farmers will be able to produce their own quality and high protein roughage. The nutritive properties of faba bean silage holds great promise as a forage in lactating dairy cows. / AFRIKAANSE OPSOMMING: Die droëmateriaal (DM) produksie en chemiese samestelling van heelplant fababone (Vicia faba) en hawer (Avena sativa) is bepaal deur vars plantmateriaal op ‘n weeklikse basis te sny. Plantmonsters van beide fababoon en hawerplante is gesny vanaf 75 tot 166 dae na plant op ‘n hoogte van ca. 10 cm bo die grond. Plantmonsters is weekliks gesny op vyf ewekansige persele met ‘n oppervlak van 0.25 m² elk. Die vars gesnyde plantmateriaal is geweeg en daarna ge-oonddroog om die DM inhoud van elke monster te bepaal. Die varsmateriaal en DM opbrengs per hektaar is bereken. Die ruproteïen (RP), ruvesel (RV), neutraal bestande vesel (NBV), suur bestande vesel (SBV), stikstof vrye ekstrak (NVE), eterekstrak (EE), kalsium (Ca) en fosfor (P) inhoud is bepaal volgens standaardlaboratorium metodes. Lineêre regressie is gebruik om die verandering in chemiese samestelling van heelplant fababone en hawer te kwantifiseer. Vars en DM produksie van heelplant fababone en hawer het toegeneem met toename in groeistadium. Gedurende die 2002 produksiejaar het varsmateriaal opbrengs vir beide fababone en hawer gepiek op 131 dae (44.7±6.9 en 28.4±7.1 ton/ha respektiewelik). Heelplant fababoon en hawer DM opbrengs het gepiek op 159 en 152 dae na plant op 9.4±1.3 en 8.8±0.7 ton DM/ha, respektiewelik. Die chemiese samestelling van beide gewasse het afgeneem met toename in groeistadium. Die RP inhoud van heelplant fababone het verminder (P<0.05) van 25.3% op 82 dae na plant tot 18.4% op 166 dae na plant vir die 2002 produksiejaar, terwyl gedurende die 2003 produksiejaar die RP inhoud verminder (P<0.05) het vanaf 28.2 tot 19.5% vanaf 75 tot 159 dae na plant. Gedurende die 2002 produksiejaar het die ruvesel % van fababone toegeneem vanaf 20.2 tot 22.6%, terwyl gedurende die 2003 produksiejaar het die ruvesel toegeneem vanaf 21.8 tot 26.5%. Die ruvesel % vir heelplant hawer het vir die 2003 produksiejaar toegeneem vanaf 25.6 tot 36.9%. Vir dieselfde tyd, het EE, Ca en P inhoud ook verminder (P<0.05), terwyl NBV, RV en SBV inhoud toegeneem (P<0.05) het. Twee melkproduksiestudies is uitgevoer om die effek van fababoonkuilvoer op voerinname, melkopbrengs en melksamestelling van Holsteinkoeie te bepaal. Fababoonkuilvoer (FBKV) is vergelyk met behulp van koeie wat hawerhooi (HH) of hawerkuilvoer (HKV) en in ‘n 50:50 kombinasie met FBKV as ruvoere ontvang het. Fababone (cv. Ascot) en hawer (cv. Sederberg) is gevestig op ‘n Glenrosa grond. Heelplant fababone is gesny en ingekuil op 145 dae na plant. Gesnyde materiaal is toegelaat om vir ‘n dag te verlep, waarna dit in ‘n bogrondse kuilvoersloot ingekuil is met behulp van ‘n kommersiële bakteriële entstof. In die eerste eksperiment is volvoere met FBKV, HH en ‘n 50:50 mengsel van FBKV en HH as ruvoer, saam met ‘n konsentraat, gevoer aan drie groepe koeie wat bestaan het uit sewe Holsteinkoeie elk. Die eksperiment is uitgevoer volgens ‘n ewekansige blokontwerp. Koeie was gemiddeld 112±44 dae in melk en het 24.0±6.2 kg melk/dag geproduseer. Melkproduksie-veranderlikes van koeie wat diëte ontvang het met verskillende ruvoere is met ‘n variansie-analise vergelyk. Die DM inname en melkopbrengs van koeie op volvoere bevattende vii FBKV, HH of ‘n 50:50 mengsel van FBKV en HH, het nie betekenisvol verskil (P>0.05) nie. Melkopbrengs was 18.9±1.9, 20.6±1.3 en 20.5±1.4 kg/koei/dag, respektiewelik. Met die uitsondering van melkureumstikstof (MUN), het melksamestelling-veranderlikes nie betekenisvol (P>0.10) verskil tussen behandelings nie. Koeie wat HH as ruvoer ontvang het, het ‘n hoër (P=0.06) MUN vlak in die melk gehad. Resultate van hierdie studie dui daarop dat FBKV effektief HH in lakterende melkkoeidiëte kan vervang. In die tweede eksperiment is volvoere, betsaande uit FBKV, hawerkuilvoer (HKV) of ‘n 50:50 mengsel van FBKV en HKV as ruvoer, saam met ‘n konsentraat aan ses Holsteinkoeie gevoer volgens ‘n dubbel 3 x 3 Latynse Vierkant omskakel proefontwerp. Elke koei het 13 kg DM van FBKV, HKV of ‘n 50:50 mengsel van FBKV en HKV ontvang as ruvoere, saam met drie verskillende konsentrate van 9 kg op ‘n natuurlike vogbasis elk. Koeie was gemiddeld 108±30 dae in melk en het 22.0±2.0 kg melk/dag geproduseer. DM inname, liggaamsmassa, melkopbrengs- en melksamestelling- veranderlikes van koeie op verskillende diëte wat verskillende ruvoere ingesluit het, is statisties vergelyk. Die DM inname en liggaamsmassa van koeie op volvoere bevattende FBKV, HKV of ‘n 50:50 mengsel van FBKV en HKV, het nie betekenisvol (P>0.10) verskil nie. Verandering in liggaamsmassa het betekenisvol (P<0.10) verskil, te wete 4.0±3.2, 8.8±3.2 en -6.0±3.2 kg, respektiewelik. Die melkopbrengs van koeie op volvoere bevattende FBKV, HKV of ‘n 50:50 mengsel van FBKV en HKV as ruvoer, het nie verskil (P>0.10) nie. Melkopbrengs was 22.8±0.4, 21.4±0.4 en 21.9±0.4 kg/koei/dag, respektiewelik. Ten opsigte van die melksamestelling-veranderlikes van die koeie op die onderskeie volvoere, was dit slegs melk RP(%) van koeie wat volvoere met FBKV ontvang het, wat betekenisvol (P<0.05) verskil het van die koeie wat HKV en die 50:50 mengsel van FBKV en HKV as ruvoer ontvang het. Melk RP(%) was 2.82±0.02, 2.93±0.02 en 2.96±0.02%, respektiewelik. Resultate van hierdie studie dui daarop dat FBKV effektief HKV in lakterende melkkoei diëte kan vervang. Die Suid-Afrikaanse databasis van in situ proteïen- en veseldegradeerbaarheidswaardes vir heelplant fababone en hawer is beperk. Die chemiese samestelling van heelplant fababone en hawer verander gedurig soos plante toeneem in ouderdom en groeistadium. Vir optimale stadium van inkuiling en voerformulering sou dit belangrik wees om DM, RP, NBV en SBV degradeerbaarheidswaardes van heelplant fababone en hawer ge-oes op verskillende groeistadiums te hê. Die doel van die studie was om die ruminale degradeerbaarheidswaardes vir heelplant fababone en hawer te bepaal. Effektiewe DM, RP, NBV en SBV degradeerbaarheidswaardes is vir fababone en hawer bepaal vir groeistadiums 117, 131, 145 en 159 dae na plant deur gebruik te maak van die in situ nylon sakkie tegniek. Drie nie-lakterende Holsteinkoeie elk toegerus met ‘n rumen- kannula is gebruik om ruminale degradeerbaarheidswaardes te bepaal. Plantmateriaal wat in Dacron sakkies afgeweeg is, is in die rumen geplaas vir 4, 8, 12, 24, 48, 72 en 96 ure. Die degradeerbaarheid van DM, RP, NBV en SBV fraksies van heelplant fababone en hawer vir vier verskillende groeistadiums (117, 131, 145 en 159 dae na plant) het nie betekenisvol (P<0.05) tussen koeie verskil nie. Die degradeerbaarheid van verskillende fraksies van beide ruvoere het verskil (P<0.05) tussen groeistadiums en inkubasie-ure. DM, RP, NBV en SBV verdwyning van heelplant fababone en hawer op 117 en 159 dae na plant het betekenisvol (P<0.05) verskil by 4, 8, 12, 24, 48, 72 en 96 inkubasie-ure. Die DM, RP, NBV en SBV verdwyningswaardes is gepas op ‘n nie-lineêre model p = a + b (1- e-ct). Die effektiewe degradeerbaarheid (P) kon bereken word met ‘n fraksionele uitvloeitempo van k = viii 0.05 vanuit die rumen. Vir heelplant fababone het parameter b (potensieel degradeerbare fraksie) en parameter c (die tempo waarteen b degradeer word) betekenisvol verskil (P<0.05) vir alle groeistadiums (117, 131, 145 en 159 dae na plant) vir degradeerbaarheidswaardes van RP, NBV en SBV. Vir hawer het parameter b en parameter c nie betekenisvol (P>0.05) tussen die vier verskillende groeistadiums (117, 131, 145 and 159 dae na plant) verskil nie. Die resultate van hierdie studie kan ‘n belangrike bydrae maak tot die Suid-Afrikaanse databasis van fababoon en hawer voedingswaardes, en kan aangewend word in dinamiese voerformulering. Die gebruik van varsgesnyde of ingekuilde heeplant fababone kan in die toekoms ‘n al groter rol speel in melkkoeivoeding in die Winterreënstreek van Suid-Afrika. Soos in die geval met lupiene, maar met ‘n hoër proteïen inhoud, sal produsente hul eie kwaliteit en hoë proteïen ruvoer kan verbou. Die voedingswaarde van fababoonkuilvoer hou groot belofte in as ruvoer vir lakterende melkkoeie.

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.

Esta tese está fundamentada em dois experimentos que visam colaborar na elucidação dos efeitos das afecções de casco sobre o desempenho reprodutivo de vacas leiteiras no Brasil. No experimento 1, um total de 57 vacas Holandesas no início da lactação foi utilizado para avaliar os efeitos das afecções de casco sobre o comportamento no estro. Os animais foram classificados de acordo com o escore dos cascos e o escore da locomoção, identificando-se assim animais com os cascos sadios e animais que apresentam lesões nos cascos. Todos os animais foram sincronizados com prostaglandina (Cloprostenol sódico). O comportamento destas vacas durante o estro foi monitorado por um aparelho de radiotelemetria (HeatWatchâ). Os dados relativos ao casco (variáveis independentes) foram associados com os seguintes dados relativos ao estro: número de montas, soma da duração das montas, duração média das montas, intensidade das montas e duração do estro (variáveis dependentes). Os resultados evidenciaram significância estatística apenas na relação funcional entre a variável dependente Duração do estro e a variável independente Escore de locomoção (P=0,0237; R²=0,0921). Quando foram considerados dois grupos, em função da presença do acometimento do casco, foi possível, utilizando a análise de variância, demonstrar diferença significativa com as variáveis Número de montas (P=0,0363); Soma da duração das montas (P=0,0280) e Duração do estro (P=0,0071). No experimento 2, 1447 vacas Holandesas foram utilizadas para avaliar a associação entre a incidência de claudicação e o desempenho reprodutivo. As vacas foram monitoradas desde o parto até a concepção, avaliando-se a relação entre a incidência de claudicação e os índices reprodutivos, compreendendo: intervalo do parto ao primeiro cio, ao primeiro serviço e à concepção; percentual de vacas com e sem claudicação que conceberam no primeiro serviço; número de doses por concepção e percentual de vacas com e sem claudicação vazias com mais de 210 dias de lactação. Os resultados demonstraram que no intervalo do parto ao primeiro cio houve diferença significativa (P=0,0021) de 16 dias; (P=0,0150) de 21 dias; (P=0,0027) de 26 dias e (P=0,0279) de 29 dias na data do cio quando a claudicação ocorreu no segundo mês, no terceiro mês, no quarto mês e no sexto mês da lactação, respectivamente. No intervalo do parto ao primeiro serviço houve diferença significativa (P=0,0159) de 13 dias; (P=0,0021) de 15 dias e (P=0,0044) de 17 dias na data do primeiro serviço quando a claudicação ocorreu no segundo mês, no terceiro mês e no quarto mês da lactação, respectivamente. No intervalo do parto à concepção e no número de doses por concepção não houve diferença significativa (P>0,05) entre os animais que apresentaram e que não apresentaram claudicação. Do total de 1447 vacas, 21,9% conceberam no primeiro serviço, sendo que 17% apresentaram claudicação e 82,6% não apresentaram; e 26% do total de vacas permaneceram vazias por mais de 210 dias em lactação, sendo que 68% apresentaram claudicação e 31,9% não apresentaram / This study is based in two experiments which aim to evaluate the effects of lameness on the reproductive performance of dairy cows in Brazil. In experiment 1,57 Holsteins cows in the beginning of the lactation were divided according to the hoof and locomotion score, respectively, and the incidence of lameness or not (healthy cows). All cows did receive were syncronized by prostaglandine (cloprostenol sódico) and its behavior during the estrus was monitored by a radiotelemetria device (HeatWatchâ). Following to this, it was possible to monitor the possible association of the lameness and the following data to the estrus: number of mounts, total duration of the mounts, duration average of the mounts, intensity of the mounts and the duration of the estrus. The results were statistically significant between the dependent variable estrus duration and the independent variable locomotion score (P=0,0237; R²=0,0921). While considering two groups, due to lameness, it was possible via the variance analysis to show the significant difference with the variable number of mountains (P=0,0363); sum of mountain duration (P=0,0280) and estro duration (P=0,0071). In experiment 2, 1447 Holsteins cows from 5 different farms were monitored from the calving date till the conception, where it was evaluated the relationship between the lameness incidence and the reproductive records, understanding: calving interval till first heat, first service and until conception; percentage of cows with and without lameness that were pregnant in the first service; number of dosis per conception and percentage of open cows over 210 days in milk with and without lameness. The results demonstrated that from the calving date till the first heat a significant difference of 16 days more (P=0,0021), 21 days more (P=0,0150), 26 days more (P=0,0027) and 29 days more (P=0,0027) when the lameness did happen in the second, third, fourth and sixth month of lactation, respectively. About the interval from the calving until the first insemination, a significant difference occurred in 13 days more (P=0,0159), 15 days more (P=0,0021) and 17 days more (P=0,0044) when the lameness did happen in the second, third and fourth months, respectively. In relation to the interval from calving to conception and the number of dose per conception, it was not found significant difference (P>0,05) between the animals with and without lameness. >From the total 1447 cows, 21,9% did get pregnant in the first service and from this animals, 17% did have lameness and 82,6% did not. Also, 26% of the total cows were open for more than 210 days in milk, and from this 68% did have lameness and 31,9% did not have lameness

Esta tese está fundamentada em dois experimentos que visam colaborar na elucidação dos efeitos das afecções de casco sobre o desempenho reprodutivo de vacas leiteiras no Brasil. No experimento 1, um total de 57 vacas Holandesas no início da lactação foi utilizado para avaliar os efeitos das afecções de casco sobre o comportamento no estro. Os animais foram classificados de acordo com o escore dos cascos e o escore da locomoção, identificando-se assim animais com os cascos sadios e animais que apresentam lesões nos cascos. Todos os animais foram sincronizados com prostaglandina (Cloprostenol sódico). O comportamento destas vacas durante o estro foi monitorado por um aparelho de radiotelemetria (HeatWatchâ). Os dados relativos ao casco (variáveis independentes) foram associados com os seguintes dados relativos ao estro: número de montas, soma da duração das montas, duração média das montas, intensidade das montas e duração do estro (variáveis dependentes). Os resultados evidenciaram significância estatística apenas na relação funcional entre a variável dependente Duração do estro e a variável independente Escore de locomoção (P=0,0237; R²=0,0921). Quando foram considerados dois grupos, em função da presença do acometimento do casco, foi possível, utilizando a análise de variância, demonstrar diferença significativa com as variáveis Número de montas (P=0,0363); Soma da duração das montas (P=0,0280) e Duração do estro (P=0,0071). No experimento 2, 1447 vacas Holandesas foram utilizadas para avaliar a associação entre a incidência de claudicação e o desempenho reprodutivo. As vacas foram monitoradas desde o parto até a concepção, avaliando-se a relação entre a incidência de claudicação e os índices reprodutivos, compreendendo: intervalo do parto ao primeiro cio, ao primeiro serviço e à concepção; percentual de vacas com e sem claudicação que conceberam no primeiro serviço; número de doses por concepção e percentual de vacas com e sem claudicação vazias com mais de 210 dias de lactação. Os resultados demonstraram que no intervalo do parto ao primeiro cio houve diferença significativa (P=0,0021) de 16 dias; (P=0,0150) de 21 dias; (P=0,0027) de 26 dias e (P=0,0279) de 29 dias na data do cio quando a claudicação ocorreu no segundo mês, no terceiro mês, no quarto mês e no sexto mês da lactação, respectivamente. No intervalo do parto ao primeiro serviço houve diferença significativa (P=0,0159) de 13 dias; (P=0,0021) de 15 dias e (P=0,0044) de 17 dias na data do primeiro serviço quando a claudicação ocorreu no segundo mês, no terceiro mês e no quarto mês da lactação, respectivamente. No intervalo do parto à concepção e no número de doses por concepção não houve diferença significativa (P>0,05) entre os animais que apresentaram e que não apresentaram claudicação. Do total de 1447 vacas, 21,9% conceberam no primeiro serviço, sendo que 17% apresentaram claudicação e 82,6% não apresentaram; e 26% do total de vacas permaneceram vazias por mais de 210 dias em lactação, sendo que 68% apresentaram claudicação e 31,9% não apresentaram / This study is based in two experiments which aim to evaluate the effects of lameness on the reproductive performance of dairy cows in Brazil. In experiment 1,57 Holsteins cows in the beginning of the lactation were divided according to the hoof and locomotion score, respectively, and the incidence of lameness or not (healthy cows). All cows did receive were syncronized by prostaglandine (cloprostenol sódico) and its behavior during the estrus was monitored by a radiotelemetria device (HeatWatchâ). Following to this, it was possible to monitor the possible association of the lameness and the following data to the estrus: number of mounts, total duration of the mounts, duration average of the mounts, intensity of the mounts and the duration of the estrus. The results were statistically significant between the dependent variable estrus duration and the independent variable locomotion score (P=0,0237; R²=0,0921). While considering two groups, due to lameness, it was possible via the variance analysis to show the significant difference with the variable number of mountains (P=0,0363); sum of mountain duration (P=0,0280) and estro duration (P=0,0071). In experiment 2, 1447 Holsteins cows from 5 different farms were monitored from the calving date till the conception, where it was evaluated the relationship between the lameness incidence and the reproductive records, understanding: calving interval till first heat, first service and until conception; percentage of cows with and without lameness that were pregnant in the first service; number of dosis per conception and percentage of open cows over 210 days in milk with and without lameness. The results demonstrated that from the calving date till the first heat a significant difference of 16 days more (P=0,0021), 21 days more (P=0,0150), 26 days more (P=0,0027) and 29 days more (P=0,0027) when the lameness did happen in the second, third, fourth and sixth month of lactation, respectively. About the interval from the calving until the first insemination, a significant difference occurred in 13 days more (P=0,0159), 15 days more (P=0,0021) and 17 days more (P=0,0044) when the lameness did happen in the second, third and fourth months, respectively. In relation to the interval from calving to conception and the number of dose per conception, it was not found significant difference (P>0,05) between the animals with and without lameness. >From the total 1447 cows, 21,9% did get pregnant in the first service and from this animals, 17% did have lameness and 82,6% did not. Also, 26% of the total cows were open for more than 210 days in milk, and from this 68% did have lameness and 31,9% did not have lameness

Darbo tikslas : Įvertinti karvių produktyvumo, somatinių ląstelių skaičiaus piene ir reprodukcinių savybių rodiklius ir nustatyti jų tarpusavio ryšius. Darbo uždaviniai: 1. Įvertinti: a) Karvių pieno kiekio ir sudėties (riebumo, baltymingumo) rodiklius; b) Somatinių ląstelių skaičių karvių piene; c) Karvių reprodukcines savybes. 2. Nustatyti karvių pieno kiekio bei sudėties, somatinių ląstelių skaičiaus ir reprodukcinių savybių tarpusavio ryšius. 3. Apskaičiuoti koreliacijos koeficientus tarp karvių pieno kiekio bei sudėties, somatinių ląstelių skaičiaus ir reprodukcinių savybių rodiklių. Išvados: 1. Įvertinus karvių pieno kiekio ir sudėties rodiklius nustatyta, kad iš visų tirtų karvių vidutiniškai primelžta 5176,442 kg pieno, gauta 223,08 kg riebalų ir 175,07 kg baltymų. Geresniu produktyvumu išsiskyrė karvės, kurios buvo laikomos B ūkyje. Iš šių karvių vidutiniškai daugiau buvo primelžta 912,99 kg pieno, gauta 29,30 kg riebalų ir 31,74 kg baltymų nei A ūkyje laikomų karvių. 2. Įvertinus SLS karvių piene nustatyta, kad tirtų karvių piene vidutinis SLS buvo 307,946 tūkst./cm3. Tai atitinka tinkamo supirkimo pienui keliamus ES reikalavimus. Tirtų karvių, laikomų A ūkyje SLS piene buvo 15,05 tūkst./cm3 mažesnis. 3. Įvertinus tirtų karvių reprodukcines savybes nustatyta, kad karvės buvo vidutiniškai 3,5 laktacijų skaičiaus, laktacija vidutiniškai truko 225,6 dienas, neveršingumo laikotarpis – 155,6 dienas, trukmė tarp apsiveršiavimų – 470,4 dienos ir vidutinis sėklinimų... [toliau žr. visą tekstą] / Aim of work: To evaluate cow productivity, somatic cell count in milk and reproduction traits and to determine correlation between them. Place of research: The work was carried out in the Department of Animal Breeding and Genetics of Veterinary Academy and also in the dairy cow‘s farm during 2011 – 2013 years of studies. The Results of Survey: Evaluation of cow milk amount and composition showed that average amount of milk from all analyzed cows was 5183.442 kg, 223.08 kg of fat was obtained, as well as 175.07 kg of proteins. Cows in farm B were more productive. 912.99 kg more milk, 29.30 kg more fat and 31.74 kg proteins were obtained from these cows on an average, in comparison to cows in farm A. Evaluation of SCC in cow milk showed that average SCC( somatic cells count) in analyzed cow milk was 307.946 thousand/cm3. It corresponds to EU requirements established for milk for production. SCC in milk of analyzed cows in farm A was 15.05 thousand/cm3 less. Evaluation of reproduction traits of analyzed cows showed that lactation of cows occurred 3.5 times on an average, average duration of lactation was 225.6 days, dry period lasted 155.6 days, number of days between parturitions was 470.4 and average number of seminations was 1.9. The research allowed to determine statistically reliable negative phenotypic correlation between SCC in milk and amount of milk (p<0.05). As productivity of cows increased, SCC in milk increased as well, it caused more frequent udder inflammation to... [to full text]

Darbo tikslas: nustatyti racionų baltymų kiekio ir kokybės įtaką karvių produktyvumui ir pieno kokybei. Darbo uždaviniai: apskaičiuoti karvėms šertų racionų energinę ir maistinę vertę. Nustatyti racionų baltymų kiekio ir kokybės įtaką karvių produktyvumui. Nustatyti racionų baltymų kiekio ir kokybės įtaką karvių pieno sudėčiai. Bandymas atliktas 2012 metais X ūkininko galvijininkystės ūkyje. Darbo tikslas buvo nustatyti racionų baltymų kiekio ir kokybės įtaką karvių produktyvumui ir pieno sudėčiai. Analogų principu atrinkta 20 karvių, kurios suskirstytos į 4 grupes (3 tiriamųjų ir 1 kontrolinė), po 5 gyvulius kiekvienoje. Vidutinis karvių produktyvumas per ankstesnę laktaciją buvo 6000 – 6300 kg pieno. Eksperimentiniais racionais karvės šertos keturis mėnesius sausio - balandžio mėn., t.y. pirmąsias 120 laktacijos dienų. Kitu laikotarpiu buvo tik registruojami produktyvumo ir pieno sudėties duomenys. Išanalizavę 2011–2012 metų X ūkio karvių racionus, jų sudėtį, energinę ir maistinę vertę, įvertinę skirtingo šėrimo poveikį produktyvumui ir produkcijos kokybei nustatėme: Didžiausias produktyvumas buvo antros grupės karvių. Lyginant su kontroline grupe, natūralaus pieno iš jų buvo primelžta 228 kg (p<0,05), o perskaičiuoto į bazinį - 666 kg (p<0,01) daugiau. Mažiausias primilžis per 10 laktacijos mėnesių buvo kontrolinės grupės karvių. Jos davė 300 kg mažiau natūralaus pieno arba 965 kg perskaičiuoto į bazinį pieną negu II (produktyviausios) grupės karvės. Daugiausia pieno... [toliau žr. visą tekstą] / The aim: to identify the diet of protein quantity and quality on cow productivity and milk quality. The tasks of the work: to calculate the cows fed rations energy content and nutritional value. Set the ration protein content and quality on milk production of cows. Set the ration protein content and quality on the composition of cow's milk. Experiment was carried out in 2012 X farmer's cattle farm. The aim of the research was to identify the ration protein content and quality on cow productivity and milk composition. Analogues of the principle of sample 20 cows, which are divided into 4 groups (3 test and 1 control), followed by five animals each. The average of productivity per cow during the previous lactation was 6000 - 6300 kg of milk. Cows were fed the experimental diets for four months of January - April., that is to say the first 120 days of lactation. The next period, there were only recorded productivity and milk composition data. The analysis of X holding the 2011-2012 cows fed rations composition, nutritional indicators, the results obtained. The maximum productivity was the second group of cows comparison with a control group of natural milk from their milk yield was 228 kg (p <0.05), and the terms of base - 666 kg (p <0.01) and more. Minimum yield within 10 months of lactation were control cows. They gave 300 kilos of liquid milk, or 965 kg of milk in terms of base than in the second (productive) group of cows. Most milk fat obtained from the second treatment... [to full text]