摘要:

Beef production traits measured on 6292 performance tested Danish Friesian bulls from 1973 to 1992 were analysed together with disease records for 4621 bulls performance tested from 1981 to 1992 using a threshold model. Univariate Gaussian and polychotomous and bivariate Gaussian‐binary mixed models with Bovine Leukocyte Adhesion Deficiency (BLAD) test information were used. Danish Friesians were found to have a larger ultrasonic muscle area than North American Holstein‐Friesians and favourable heterosis was observed for daily gain and feed utilization. Carriers of BLAD were observed to have poorer feed utilization than non‐carriers and tended to grow slower and to have a lower incidence of disease treatments. Estimated heritabilities for beef production traits ranged from 0.29 to 0.39. For disease frequency analysed as polychotomous and as binary, the estimated heritabilities ranged from 0.08 to 0.19 and from 0.12 to 0.33, respectively. Simulation showed that heritability estimates tended to be biased with increasing number of pooled categories. Phenotypic and genetic correlations between disease frequency and beef production traits ranged from — 0.32 to 0.10 and from — 0.43 to 0.23, respectively.

ISSN:0906-4702    

DOI:10.1080/09064709709362364

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Silage effluent, normally considered a potential environmental pollutant, can be successfully fed to livestock, but must be stored from the time of drainage prior to feeding. In this study, effluent from ensiled direct‐cut grass was retained in closed‐drainage tower silos, such that silage and effluent were stored together but the effluent was released prior to the silage being fed. Silage quality was good, similar to that from a silo with normal open drainage. The quality of silage effluent from the closed‐drainage silo tended to be better than that of effluent stored in a separate tank. Decreased compaction of the ensilage mass, due to collection of effluent in the silo, led to a 13% reduction in the silo's crop capacity and 10% in its silage capacity, but no reduction in its total feed dry matter (DM) capacity (silage plus effluent). The total storage volume, however, was better utilized for feed DM when silage and effluent were stored together in the silo than when stored separately in silo plus tank. However, owing to problems caused by effluent leakage via trapdoors and small holes in the silo wall, the use of silos with open drainage and storage of effluent in separate tanks is recommended.

ISSN:0906-4702    

DOI:10.1080/09064709709362365

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Three feeding experiments, each with 24 cows, were performed to evaluate the use of effluent from grass silage as feed. The quality of silages produced in open‐drainage silos and closed‐drainage silos was also compared. Silage and effluent were fedad libitumwith concentrate supplements. Animals readily consumed effluent at 30 kg day−1on average, equivalent to 2.2 kg dry matter (DM) day−1. Silage intakes decreased by 1 kg DM day−1when silage plus effluent was fed as compared with silage alone, while total roughage intake (silage plus effluent) increased by 1.2 kg DM day−1. Milk yields and fat, protein, and lactose contents tended to increase for cows receiving effluent. Increases in milk yield were small, however, relative to the increases in DM intake, indicating reduced feed conversion efficiency when effluent was fed. Intakes of silage stored in the presence of effluent tended to be lower than those of silage from which effluent had been drained, but milk yield and milk composition were unaffected.

ISSN:0906-4702    

DOI:10.1080/09064709709362366

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

A new method for defining the protein quality in feedstuffs and pig diets, based on the amino acid composition of true ileal digestible protein relative to the pattern of ideal protein, is introduced.

ISSN:0906-4702    

DOI:10.1080/09064709709362367

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Barley, oats, and wheat were stored anaerobically for three months after adjusting the dry matter content to 60%. The content of true protein was reduced when grains were high‐moisture stored, but the amino acid content was not affected to the same extent. High‐moisture storage decreased the soluble dietary fibre and solubleβ‐glucan content in barley and oats, and simultaneously the extract viscosity of the grain was reduced to the same level as for wheat. In two experiments with two to five week old broiler chickens given diets with 70% dried or high‐moisture stored grain, feed:gain ratio was reduced (P <0.05) to the same level as for the wheat diets when high‐moisture stored barley instead of dried barley was fed, and digestibility of dry matter, organic matter, fat, and minerals increased (P <0.05). Weight gain and cleanness of cages also increased (P <0.05), and the relative size of the digestive tract was reduced (P <0.05). Digestibility of dry matter, organic matter, and minerals increased (P <0.05) when highmoisture stored oats compared to dried oats were fed, and highmoisture storage of wheat increased (P <0.05) P and Ca digestibility.

ISSN:0906-4702    

DOI:10.1080/09064709709362368

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

One‐hundred‐and‐twenty Danish Friesian (DF) bull calves were used in a 3 × 2 factorial experiment with three floor space allowances in pens with fully slatted floor and two feeding‐trough arrangements. The floor space per animal was 1.4 m2(group L), 1.7 m2(group M), and 2.5 m2(group H) from approximately 100 kg to about 300 kg live weight (period I). From approximately 300 kg until slaughter at 460 kg live weight (period II), the space allowance was increased by about 25% to 1.8 m2, 2.2 m2and 3.1 m2per animal, respectively. The concentrate was fedad libitumin troughs with five eating places per pen (5 places/5 animals) or in one self‐feeder per pen (1 place/5 animals). Besides concentrate, all the animals were fed chopped barley strawad libitumin a separate trough. Increased floor space allowance did not affect daily feed intake in either period I or period II. An increased space allowance from L to M and H increased the growth rate in both period I (1357, 1402 and 1429 g/day; P = 0.05) and period II (1193, 1258 and 1340 g/day; P = 0.14). Correspondingly, the feed conversion ratio expressed as Scandinavian Feed Units (SFU) per kg gain was decreased in period I (4.03, 3.75 and 3.84;P= 0.01) and period II (6.62, 6.21 and 6.04;P=0.l7).In the full experimental period, the average carcass gain was 665, 687 and 719 g/day for group L, M and H, respectively (P =0.05); SFU per kg carcass gain was 9.92, 9.33 and 9.15 (P = 0.02). Floor space allowance did not significantly affect dressing percentage, EUROP classification (conformation, fatness), carcass composition or meat quality (colour, pigment, intramuscular fat, shear force value). The number of eating places did not significantly affect any of the observed traits.

ISSN:0906-4702    

DOI:10.1080/09064709709362369

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Economic benefits of improving litter size, body weight (i.e. pelt length) and pelt quality were estimated in mink. Effects of the size of the litter in which the kit was born, on pelt length and pelt quality, were also assessed. The traits were recorded during a selection experiment involving the traits litter size, body weight and underfur density. Skins originating from litters of ≥10 kits tended to be smaller and sold at a lower price, compared with pelts from smaller litters. Litter size did not seem to affect fur quality. Pelt quality score decreased with increasing September weight. Pelts of animals with September weights of < 2000 g and pelting weights of < 2300 g had a lower sales price than pelts of heavier animals. Pelt quality had only a small effect on the price The highest economic gain was achieved by increasing litter size. The net revenue from each extra kit per litter was, in Swedish Kronor, SEK 70, 122 and 170 at an average sales price of SEK 150, 200 and 250, respectively.

ISSN:0906-4702    

DOI:10.1080/09064709709362370

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:0906-4702    

DOI:10.1080/09064709709362363

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor