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971.
The anatomy of the neck and forelimb of Chrysochloris asiatica is described and illustrated. The sequence of events during digging and modifications for fossorial action are described. Modifications include the appearance of a third bone in the forearm; the shortening and fusion of bones in the manus; enlarged processes on the scapula, humerus and ulna for greater muscle attachment; enlarged neck muscles and a dip in the spine in the cervical region to accommodate these and the enlarged shoulder muscles; an enlarged occiput for insertion of the powerful neck muscles; a greatly enlarged triceps and movement of the shoulder girdle to a position anterior to that normal in mammals. The possibility of the third forearm bone being the ossified tendon of a flexor muscle is discussed, without any conclusion being reached as to its true origin.  相似文献   
972.
The journal     
Extract

At the Annual General Meeting of the New Zealand Veterinary Association in 1951 a motion was carried “that this meeting recommend that a journal be started, and ask Council to investigate the matter from all aspects, and to report to the next Annual General Meeting.” To implement the wishes of the meeting, Council appointed a subcommittee which reported to the Annual General Meeting of 1952. The report, after dealing with costs and publishable material, recommended as follows:—  相似文献   
973.

Four cow routing treatments related to fully automatic milking were compared consecutively in one group of 24 Holstein Friesian cows. The objective of the experiment was to investigate how cow traffic towards the automatic milking system (AMS) should be routed and whether a preselection or a waiting area in front of the AMS should be used. The treatments were (1) free routing with selection of cows in the AMS (FREE); (2) free routing with a preselection system in front of the AMS (FREE_SS); (3) free routing with a preselection system and a waiting area in front of the AMS (FREE_WA); and (4) one-way gates resulting in forced routing with preselection and a waiting area in front of the AMS (FORCED_WA). Evaluation of the treatments revealed that FREE may be questionable with regard to the cows' visiting frequency to the AMS and that the use of a waiting area in combination with free routing (FREE_WA) may slow down the passing through the AMS. FORCED_WA may be the best option in relation to the cows' use of the AMS, but this traffic system seems to postpone or even thwart the feeding. The treatment that appears to give the best results is FREE_SS. The type of AMS visit appeared to have a marked influence on the cows' subsequent behaviour. Cows returned to the AMS sooner after non-milking visits and failed attachments (P<0.01). This increases the occupation rate of the AMS and may induce some extra unrest in the herd.  相似文献   
974.
Abstract

This study investigated the effectiveness of the proprietary laser methane detector (LMD) in enteric methane monitoring from individual dairy cows and sheep. Three experiments were carried out. First, the relationship between LMD and indirect open-circuit respiration calorimetric chamber measurements was tested. Sensitivity and specificity for cows were 95.4% and 96.5%. For sheep, sensitivity was 93.8% and specificity was 78.7%. Second, the effect of cow's activity on enteric methane emissions was investigated. During drinking and feeding, cows produced significantly more (p<0.001) methane emissions than when idle. Third, effect of different micrometeorological factors on LMD measurements under outdoor grazing conditions was investigated. Wind speed, relative humidity, pressure and wind direction relative to methane point-source had significant effect on methane measurements (p<0.001) under outdoor conditions. With further validation, the LMD has potential to provide reliable estimates from ruminants and hence provide a useful technique for on-farm monitoring and decision support for greenhouse gas mitigation strategies.  相似文献   
975.
Abstract

Rainfall variability is a major determinant of system dynamics and profitability of livestock enterprises in arid and semi‐arid environments. Range managers consequently require detailed information on the financial and ecological implications of various stocking strategies in order to formulate viable management systems. Data collected over seven seasons (1986–1993), from a series of extensive grazing trials in the semi‐arid savanna of KwaZulu‐Natal with cattle stocked at three rates (0.17, 0.23 and 0.30 LSU ha?1) were used to develop a bioeconomic stocking model (LOWBEEF). The model comprised two biological sub‐models (BEEF and GRASS), and an integrated economic component. The BEEF sub‐model related seasonal live mass gain to stocking rate and rainfall. The GRASS sub‐model related residual herbage at the end of summer to summer stocking intensity, range condition (indexed as the sum of proportions of three key forage species, Themeda triandra, Panicum maximum and P. coloratum) and rainfall. The period over which supplementary feeding would be required to maintain cattle mass was related to residual summer herbage mass. The biological sub‐models were linked to an economic component model (ECON) to reflect the influence of various environmental and economic parameters on profitability.  相似文献   
976.
Extract

First let me express my appreciation of being the recipient of a Fulbright Fellowship for research in New Zealand and also for the privilege of discussing brucellosis before the New Zealand Veterinary Association.  相似文献   
977.
978.
Extract

Whenever disease is discussed in terms of beef production, in New Zealand it is certain to include infertility (brucellosis, vibriosis), metabolic diseases (bloat, staggers) and possibly exotic diseases and their prevention. On the rare occasion that parasitism is considered it tends somehow to find itself, along with selenium and other deficiency diseases, under a general heading of nutrition or management. This is probably because, while parasitism is still recognized as an infectious disease with clear clinical signs in severe cases, the tendency is to ignore its presence unless nutritional or management changes force a confrontation.  相似文献   
979.
980.
Sir, — In recent years, much research effort has been directed towards identifying the cause of Ryegrass staggers (RGS). Many promising leads have been investigated, including studies of fungi in soil, ryegrass leaves, and dead leaf litter that could produce tremorgenic mycotoxins(3). Several groups of fungi produce tremorgens(4) which, when injected into sheep, produce symptoms similar to those in field outbreaks of RGS. However, under field conditions, populations of these fungi have not been shown to differ significantly between toxic and non-toxic pasture(7) (McKenzie &; Byford, unpublished data).  相似文献   
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