The Effect of Ambient Temperature on The Death Rate, Reject Rate, Dressing Percentage, and Economic Loss in Broilers During Transport to Slaughterhouse

SUMMARYOne hundred and fifty-nine Corriedale x Dorset Horn lambs were slaughtered at 32 kg live weight at ages varying from 98 to 303 days. The youngest lambs were from ewes on a pasture with high herbage availability and had not been weaned; the next youngest were from the same group of ewes but had been weaned at 6 or 12 weeks of age. Older lambs had been weaned at 6, 12 or 29 weeks from ewes on a pasture with low herbage availability. The weaned lambs grazed either a phalaris or a lucerne pasture.Lambs that grazed lucerne had a greater dressing percentage and a heavier carcass. Over all lambs, ultimate pH of the m. semimenxbranosus ranged from 5·4 to 6·0 and Warner-Bratzler shear values increased twofold from lowest to highest pH. Minimum ambient temperatures during the nights before the slaughter days ranged from 13 to – 1°C; ultimate pH increased by 0·25 units with decreasing temperature over the range, equivalent to an increase in shear value of 26%. Shear values adjusted for pH differences increased from about 3·4 kg/cm2 at 130 days of age to about 7·5 kg/cm2 at 300 days.Visual attractiveness of 13th rib chops increased with increasing area of the m. longissimus dorsi. Attractiveness was least at intermediate dominant wavelength (redness) of this muscle, but was not related to its reflectance. Optimum fat depth was about 2·4 mm. In general, chops from younger lambs were more attractive than those from older lambs.

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An analysis of pre-weaning deaths in rabbits with special emphasis on enteritis and pneumonia. I. Non-genetic sources of variation

Animal Science ◽

10.1017/s0003356100038290 ◽

1967 ◽

Vol 9 (1) ◽

pp. 87-92 ◽

Cited By ~ 5

Author(s):

W. C. Rollins ◽

R. B. Casady

Keyword(s):

Ambient Temperature ◽

Litter Size ◽

Death Rate ◽

The Other ◽

Experiment Station ◽

Sources Of Variation ◽

The U.S

Non-genetic sources of variation in pre-weaning death losses due to enteritis or pneumonia have been investigated using records of 15,329 rabbits born during the years 1946–61 in the random bred colony at the U.S. Rabbit Experiment Station at Fontana, California. Under consideration were periods of years, season within years, litter size, parity of doe, and fostering.For enteritis there was a statistically significant effect of season due to a negative regression of death rate on ambient temperature. For pneumonia, periods of years were statistically significant due to an increase in later years in deaths during the first 14 days of life. The other sources of variation studied were of negligible importance.

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SEM of non-coated hepatocellular cytoskeleton of perfused livers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111641 ◽

1984 ◽

Vol 42 ◽

pp. 306-307

Author(s):

S.W. French ◽

N.C. Benson ◽

C. Davis-Scibienski

Keyword(s):

Ambient Temperature ◽

Critical Point ◽

Protease Inhibitors ◽

Metal Deposition ◽

Heat Damage ◽

Detergent Extraction ◽

Cytoskeletal Elements ◽

Triton X ◽

Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

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Formation of Dislocation Channels in Neutron Irradiated Molybdenum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096618 ◽

1972 ◽

Vol 30 ◽

pp. 672-673

Author(s):

S. Mahajan

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Ambient Temperature ◽

Room Temperature ◽

Channel Formation ◽

Early Stages ◽

Transmission Electron ◽

Three Stages ◽

Two Stages ◽

Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

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Crystallographic Characterization of Dislocation Loops in Irradiated Tungsten

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101190 ◽

1968 ◽

Vol 26 ◽

pp. 290-291

Author(s):

Robert C. Rau

Keyword(s):

Electron Microscope ◽

Ambient Temperature ◽

Dislocation Loops ◽

Polycrystalline Specimen ◽

Post Irradiation ◽

Neutron Fluences

Previous work has shown that post-irradiation annealing, at temperatures near 1100°C, produces resolvable dislocation loops in tungsten irradiated to fast (E > 1 MeV) neutron fluences of about 4 x 1019 n/cm2 or greater. To crystallographically characterize these loops, tilting experiments were carried out in the electron microscope on a polycrystalline specimen which had been irradiated to 1.5 × 1021 n/cm2 at reactor ambient temperature (∼ 70°C), and subseouently annealed for 315 hours at 1100°C. This treatment produced large loops averaging 1000 Å in diameter, as shown in the micrographs of Fig. 1. The orientation of this grain was near (001), and tilting was carried out about axes near [100], [10] and [110].

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Voids in Quenched Nickel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101074 ◽

1968 ◽

Vol 26 ◽

pp. 266-267

Author(s):

J. J. Laidler

Keyword(s):

Electron Beam ◽

Ambient Temperature ◽

Cooling Rate ◽

Three Dimensional ◽

Cooling Curve ◽

Polycrystalline Nickel ◽

Quenching Temperature ◽

Long Tail ◽

Diffusion Pump

The presence of three-dimensional voids in quenched metals has long been suspected, and voids have indeed been observed directly in a number of metals. These include aluminum, platinum, and copper, silver and gold. Attempts at the production of observable quenched-in defects in nickel have been generally unsuccessful, so the present work was initiated in order to establish the conditions under which such defects may be formed.Electron beam zone-melted polycrystalline nickel foils, 99.997% pure, were quenched from 1420°C in an evacuated chamber into a bath containing a silicone diffusion pump fluid . The pressure in the chamber at the quenching temperature was less than 10-5 Torr . With an oil quench such as this, the cooling rate is approximately 5,000°C/second above 400°C; below 400°C, the cooling curve has a long tail. Therefore, the quenched specimens are aged in place for several seconds at a temperature which continuously approaches the ambient temperature of the system.

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