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    A bio-economic modelling comparison of a Friesian Bull-Beef system and a New Generation Beef system with Friesian bulls slaughtered at 10–14 months old
    (Taylor and Francis Group on behalf of the Royal Society of New Zealand, 2024-02-05) Farrell LJ; Morris ST; Kenyon PR; Tozer PR
    Finishing of dairy-origin calves in an accelerated ‘New generation beef’ (NGB) beef finishing system for slaughter up to 14 months of age has potential co-sector benefits. These include production efficiencies and a reduced number of dairy calves slaughtered at a very young age. In the present study, a NGB system and an 18-month Bull-Beef system were first modelled separately, both purchasing three-month-old Friesian bull calves. Then Mixed systems with varying proportions of both NGB and Bull-Beef animals were modelled. Production, feed balance and profitability were compared, using cash operating surplus (COS) as a profit indicator. In the NGB scenario, double the number of animals were finished compared with the Bull-Beef scenario; however, monthly feed demand was less synchronous with predicted pasture supply, requiring more feed transfer via pasture baleage. The COS for the NGB system was $−571/ha, with less income and greater costs than the Bull-Beef system (COS = $2026/ha). Break-even prices for NGB animals were up to 74% above current prices, but break-even prices were less in Mixed systems with a greater proportion of Bull-Beef animals. Without high price premiums, challenges remain for the NGB systems appeal to beef finishers due to their low slaughter weights and sale prices.
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    The effects of fasting and transport on calves : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science at Massey University
    (Massey University, 1998) Todd, Sarah Elizabeth
    The welfare of domestic animals is becoming increasingly important in New Zealand. Consequently, Codes of Recommendations and Minimum Standards are produced by the Animal Welfare Advisory Committee to maintain adequate standards of welfare for animals in our care. These Codes are updated to incorporate new knowledge which may improve welfare standards further. There is one such Code for the welfare of bobby calves. In New Zealand, calves born to dairy cows that are not required for replacements in the herd are slaughtered for human consumption. These 'bobby calves' are exposed to a number of factors which have the potential to compromise welfare. Work in this thesis is based on the recommendations and minumum standards given in the bobby calf code. The general aim of this work was to investigate the combined effects of transport and nutrition on bobby calves, and to assess the ability of the calves to operate within their physiological capacity withoutsignificant welfare compromise during the bobby process. In this study the metabolic effects of feeding and fasting hand-reared dairy calves aged 1-2 weeks were examined over a period of 30 hours. Parameters used to assess the response to feeding and fasting included PCV and plasma concentrations of total proteins, glucose, triglycerides, beta-hydroxybutyrate and urea. In mild climatic conditions and with access to water at all times, it was found that feeding calves the recommended volume of colostrum or milk at 12 hourly intervals was sufficient to maintain high glucose concentrations between feeds. A period of 30 hours without food had minimal adverse effects on calves as they were able to maintain energy levels during this time without excessive use of endogenous energy reserves. There was no evidence to suggest that significant dehydration had occurred. Work in this study included examination of the metabolic effects of transport duration and stocking density in calves that were deprived of food for 30 hours. PCV and plasma concentrations of total proteins, glucose, triglycerides, beta-hydroxybutyrate, urea, creatine phosphokinase and lactate were measured. Three hours of transport at the recommended stocking density (0.2m2/calf) caused minimal adverse effects in food-deprived calves. Food-deprived calves transported for 12 hours at the recommended density maintained normoglycemia for 6 hours longer than non-transported food-deprived calves. This was thought to be caused by a mild increase in physical activity resulting from the need to maintain balance during transport. Thus the physical activity probably produced a glucose-sparing effect by mobilising muscle glycogen. The response of food-deprived calves transported for 12 hours at half the recommended density (0.4m2/calf) was similar to that of non-transported, food-deprived calves. This suggests minimal physical activity occurred at the lower stocking density and this was attributed to the fact that most of these calves lay down during transport. In this study these initial metabolic responses of calves to feeding were evaluated after 30 hours of food-deprivation in transported and non-transported calves, and immediately after transport of 3 or 12 hours duration. Parameters measured included PCV and plasma concentrations of total proteins, glucose, triglycerides, urea and lactate. Feeding after 30 hours without food apparently caused a decrease in glucose clearance. It is thought that this may have resulted from a metabolic overcompensation due to delayed adjustment of hormones and metabolites from the starved state to the fed state. Feeding immediately after transport restored plasma glucose levels to be within the normal range within 3 hours. As indicated by the parameters measured in this study, hand-reared dairy calves appear to tolerate the combined effects of transport and food-deprivation quite well. However the present experiments were conducted in mild climatic conditions. Air temperatures ranged from 7-13 °C and there was little wind or no rain. In situations of climatic extremes, the physiological capacity of calves to withstand the bobby process may not be as great. At higher temperatures there is a risk of dehydration. At lower temperatures, especially combined with wind and rain, an increased metabolic rate may be required to fuel heat production so that endogenous body reserves may not last as long during times of food-deprivation.
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    The significance of "navel ill" and other lesions at post-mortem inspection of bobby calves : a thesis presented in partial fulfilment (70%) of the requirements for the degree of Master of Veterinary Science, Massey University, New Zealand
    (Massey University, 1990) Biss, Monique Elizabeth
    Calves slaughtered for bobby veal in New Zealand are considered a public health risk if "acute inflammation of the umbilicus" is present at slaughter, because it is believed that the consumption of veal derived from these calves may subsequently "cause food-poisoning" as a result of bacterial dissemination throughout the carcass. This belief, however, has not been fully validated. During the 1989 season, 54 calves were condemned for "navel ill" (0.465% of the total slaughtered) at Waitaki International's Feilding export slaughterhouse. Carcasses from these calves, along with 31 normal carcasses, were examined for the presence of septicaemia (Part I). The study involved the detailed gross examination of the carcass and viscera, together with microbiological examination of umbilical vein, liver and muscle, and histopathological examination of the umbilical vein, liver, and kidney. The working definition of septicaemia for the purposes of this study was the presence of large numbers of bacteria in the general circulation, involving slight or absent clinical signs and with or without gross evidence of early systemic infection in the carcass. Bacteraemia was defined as the presence of smaller numbers of bacteria in the general circulation, with or without gross evidence of localisation in the carcass. Although differing from the several definitions, particularly of septicaemia, in the literature, these were proposed as appropriate definitions in the context of the slaughterhouse. The presence or absence of septicaemia was determined on the basis of the combined gross lesions in the carcass, histopathological lesions in the liver and kidney, and microbial isolates from the liver and carcass musculature. The presence of infection extending from the umbilicus was determined by histopathological and microbiological examination of the umbilical vein near the liver. "Navel ill" could be sub-classified into three categories: (1) Umbilical vessel infection and carcass lesions indicative of systemic spread, with or without umbilical infection. (2) Umbilical vessel infection, with or without umbilical infection. (3) Umbilical infection alone. Three carcasses condemned for "navel ill" had no abnormalities of the umbilicus or umbilical vessels. Of the remaining 51 carcasses, one (2%) had gross, histological and microbiological evidence of septicaemia, and seventeen (33%) had lesions indicative of bacteraemia or septicaemia. The proportion of condemned carcasses which were bacteraemic decreased as the condemnation criteria expanded to include all three categories of "navel ill". There was a significant risk of bacteraemia in carcasses from ail sub-categories of "navel ill", except category (3), when compared with normal carcasses. Insufficient data were generated to allow assessment of the risk of septicaemia being present in carcasses from calves with "navel ill". A second study was undertaken later in the 1989 season, and involved the detailed gross examination and description of 371 calves condemned for any reason at six export slaughterhouses; five in the North Island and one in the South Island. The major disease entities found in calves of this age and resulting in carcass condemnations were "navel ill" (197 (0.50%) carcasses), pneumonia (75 (0.19%) carcasses), arthritis (31 (0.08%) carcasses, and "white spotted kidneys" (30 (0.08%) carcasses). Peritonitis, jaundice, hepatic abscesses and "fever" occurred at very low rates (< 0.03%), while other lesions occurred sporadically. The current inspection system in New Zealand requires calves with "acute inflammatory lesions" to be condemned. In this study, this requirement resulted in the condemnation of virtually all diseased calves, whether the disease was acute, chronic, generalised, localised or non-infectious in nature. There was, however, considerable variation found in the severity, age and likely pathogenesis of the lesions in each disease category. Because this "blanket" approach to disease in the bobby calf leads to unnecessary condemnation and wastage, it is suggested that more appropriate judgement criteria such as the trimming of localised infectious and traumatic lesions should be considered.