Carcass characteristics of cattle differing in Jersey proportion

peer-reviewedComparison of alternative dairy (cross-)breeding programs requires full appraisals of all revenues and costs, including beef merit. Few studies exist on carcass characteristics of crossbred dairy progeny originating from dairy herds as well as their dams. The objective of the present study was to quantify, using a national database, the carcass characteristics of young animals and cows differing in their fraction of Jersey. The data set consisted of 117,593 young animals and 42,799 cows. The associations between a combination of sire and dam breed proportion (just animal breed proportion when the dependent variable was on cows) with age at slaughter (just for young animals), carcass weight, conformation, fat score, price per kilogram, and total carcass value were estimated using mixed models that accounted for covariances among herdmates of the same sex slaughtered in close proximity in time; we also accounted for age at slaughter in young animals (which was substituted with carcass weight and carcass fat score when the dependent variable was age at slaughter), animal sex, parity of the cow or dam (where relevant), and temporal effects represented by a year-by-month 2-way interaction. For young animals, the heaviest of the dairy carcasses were from the mating of a Holstein-Friesian dam and a Holstein-Friesian sire (323.34 kg), whereas the lightest carcasses were from the mating of a purebred Jersey dam to a purebred Jersey sire which were 46.31 kg lighter (standard error of the difference = 1.21 kg). The young animal carcass weight of an F1 Holstein-Friesian × Jersey cross was 20.4 to 27.0 kg less than that of a purebred Holstein-Friesian animal. The carcass conformation of a Holstein-Friesian young animal was 26% superior to that of a purebred Jersey, translating to a difference of 0.78 conformation units on a scale of 1 to 15. Purebred Holstein-Friesians produced carcasses with less fat than their purebred Jersey counterparts. The difference in carcass price per kilogram among the alternative sire-dam breed combinations investigated was minimal, although large differences existed among the different breed types for overall carcass value; the carcass value of a Holstein-Friesian animal was 20% greater than that of a Jersey animal. Purebred Jersey animals required, on average, 21 d longer to reach a given carcass weight and fat score relative to a purebred Holstein-Friesian. The difference in age at slaughter between a purebred Holstein-Friesian animal and the mating between a Holstein-Friesian sire with a Jersey dam, and vice versa, was between 7.0 and 8.9 d. A 75.8-kg difference in carcass weight existed between the carcass of a purebred Jersey cow and that of a Holstein-Friesian cow; a 50% Holstein–Friesian-50% Jersey cow had a carcass 42.0 kg lighter than that of a purebred Holstein-Friesian cow. Carcass conformation was superior in purebred Holstein-Friesian compared with purebred Jersey cows. Results from this study represent useful input parameters to populate simulation models of alternative breeding programs on dairy farms, and to help beef farmers evaluate the cost-benefit of rearing, for slaughter, animals differing in Jersey fraction.This publication arose from research supported in part by a research grant from Science Foundation Ireland (Dublin) and the Department of Agriculture, Food and Marine on behalf of the Government of Ireland under the Grant 16/RC/3835 (VistaMilk; Dublin, Ireland) as well as funding from the Research Stimulus Fund (BreedQuality and GREENBREED; Dublin, Ireland) and Meat Technology Ireland (MTI; Dublin, Ireland), a co-funded industry/Enterprise Ireland project (TC 2016 002)

Accuracy of predicting milk yield from alternative milk recording schemes

peer-reviewedThe effect of reducing the frequency of official milk recording and the number of recorded samples per test-day on the accuracy of predicting daily yield and cumulative 305-day yield was investigated. A control data set consisting of 58 210 primiparous cows with milk test-day records every 4 weeks was used to investigate the influence of reduced milk recording frequencies. The accuracy of prediction of daily yield with one milk sample per test-day was investigated using 41 874 testday records from 683 cows. Results show that five or more test-day records taken at 8-weekly intervals (A8) predicted 305-day yield with a high level of accuracy. Correlations between 305-day yield predicted from 4-weekly recording intervals (A4) and from 8-weekly intervals were 0.99, 0.98 and 0.98 for milk, fat and protein, respectively. The mean error in estimating 305-day yield from the A8 scheme was 6.8 kg (s.d. 191 kg) for milk yield, 0.3 kg (s.d. 10 kg) for fat yield, and −0.3 kg (s.d. 7 kg) for protein yield, compared with the A4 scheme. Milk yield and composition taken during either morning (AM) or evening (PM) milking predicted 24-h yield with a high degree of accuracy. Alternating between AM and PM sampling every 4 weeks predicted 305-day yield with a higher degree of accuracy than either all AM or all PM sampling. Alternate AM-PM recording every 4 weeks and AM + PM recording every 8 weeks produced very similar accuracies in predicting 305-day yield compared with the official AM + PM recording every 4 weeks

Hazard Perception and Reporting

Reporting of hazards is a key aspect of safety management in industry, but relatively little empirical investigation of reporting has been undertaken. This research reports on an investigation that was carried out in the Science gallery at Trinity College Dublin to explore the detection and reporting of hazards by members of the public. Three simulated hazards were developed and placed around the risk lab. The experiment was designed to assess the capacity to recall recognise and report hazards of the participants by means of an exit survey. Participants performed better at recognition than recollection with no actual reporting of hazards recorded. The results validated some of the findings suggested by the literature and can assist in the development of a new experimental methodology as training within organizations to improve awareness of hazards and reporting practices

Strategija europskog uzgoja goveda Fleckvieh za optimiziranje uzgoja dvostruke namjene osobito za proizvodnju govedine

Želimo li da Simentalac/Fleckvieh ostane pasmina dvostruke namjene morat će se nastaviti istodobno poboljšavati mesne i mliječne osobine. Nastojanje da se odobre i zatim održavaju dvije alternativne uzgojne strategije unutar jedne pasmine povezano je s poteškoćama. Možda će biti teško raditi unutar rodoslovnika u smislu postizanja sporazuma a zatim kako se rodoslovnik održava. Da li će biti potrebne dvije sekcije u rodoslovniku i ako je tako gdje će se bilježiti živo¬tinje, te rezultati parenja među odabranim mliječnim i mesnim značaj¬kama? Ovo se pitanje pojavilo u Irskoj. Problem je riješen pitanjem kako najbolje poslužiti potrebama mesne industrije. Tako se došlo do prepoznavanja niza osobina te na toj osnovi do pokazatelja što mogu poslužiti komercijalnim uzgajivačima goveda, bili oni u proizvodnji mlijeka ili mesa. Osnovan je, zatim, sustav genetske procjene za identi¬ficiranje uzgojne vrijednosti svih životinja za različite pokazatelje. Uzgajivači i farmeri slobodno donose odluke o ekonomskom uzgoju, naj¬boljem za njihove određene potrebe. U Irskoj, na primjer, očekuje se da će se razviti određeni stupanj specijalizacije kao rezultat stva¬ranja ovih pokazatelja u vezi s općim trendovima u industriji nakon parenja. Neki se proizvođači mogu specijalizirati za proizvodnju zamjenskih uzgojnih ženka na temelju na osnovi majčinskih pokazatelja, dok će se drugi uzgajivači za priplod koncentrirati na proizvodnju rasplodnih bikova za upotrebu u proizvodnji govedine, gdje će biti važna samo lakoća izravnog telenja uz indekse proizvodnje govedine. Uvođenje dvaju uzgojnih ciljeva za jednu pasminu može konačno dati samo dvije izrazite pod-pasmine