Reproductive problems of reptiles. Proceedings of the Association of Reptilian and Amphibian Veterinarians. pp 101-105 TINKLE, D. W. (1959) Additional remarks on extra-uterine egg migration in turtles. Herpetologica 15, 161-162 UNITED STATES DEPARTMENT OF COMMERCE (1997) Endangered Species Act biennial report to Congress on the status of recovery programs,

SummaryNinety-nine lactating British Friesian cows, in their second and subsequent lactations, were divided into two groups receiving ad libitum grass silage. The cows in group A were offered silage individually through Calan Broadbent gates while those in group B were given 24 h/day access to a self-feed silage clamp. The crude protein (CP), acid-detergent fibre (ADF), neutral-detergent fibre (NDF), in vitro digestible organic matter and estimated metabolizable energy (ME) values in the D.M. of the silage were 140, 373, 584, 610g/kg D.M. and 9·7 MJ/kg D.M. respectively. The cows in each group received either 11kg/day fresh weight of concentrate S in which the principal energy source was cereal starch or 9 kg/day fresh weight of concentrate F containing mixed high quality fibre sources plus 2 kg/day fresh weight of concentrate S. The CP, ADF, NDF, starch and sugar concentrations in concentrates S and F were 203, 71, 204, 444, and 44 and 202, 147, 329, 116 and 149g/kg D.M., respectively.The only significant difference produced by method of silage allocation was that groupfed cows gained more live weight (P < 0·01) than those fed individually.Over the whole experimental period the mean silage D.M. intake of cows fed concentrate F in group A was 0–5 kg/day higher than those fed concentrate S. However, in early lactation the benefit to silage intake in favour of concentrate F was 1 kg D.M./day.In group A estimated intakes derived from calculated ME inputs and outputs were markedly lower than the observed intakes, but were similar to correspondingly derived estimates for group B.Although concentrate type did not affect milk yield, concentrate F was associated with a higher fat concentration and yield (P &lt;0–05) but a lower protein concentration (P &lt; 0·001) and a slightly lower yield.The in vivo digestibility coefficients for D.M. and organic matter determined in lactating dairy cows given concentrates S and F respectively were similar (0·724 v. 0·716 and 0·749 v. 0·742) but that for ADF was significantly (P < 0·001) higher (0·565 v. 0·673) in the ration containing concentrate F than in that containing concentrate S.Estimates of the mean efficiency of utilization of the production ME made on a weekly basis were unaffected by concentrate type.

This review provides an assessment of research findings into the current practices and standards and the principles and aspirations for organic dairy production, with respect to the health and welfare of the dairy cow. The relationships between the four main factors: management, environment, genetics and nutrition and their impact on the health and welfare status of organic dairy cows are considered. The concept that good animal health and welfare is more than merely the absence of disease, with behavioural aspects of health and welfare such as physiological and psychological needs, is also discussed. These factors are inter-related and important in all dairy systems, irrespective of whether the system is organic, low-input or intensive. Incidences of individual clinical and sub-clinical diseases that are recorded in conventional dairy systems also occur in organic dairy systems, with infertility, lameness and mastitis being the major problems. However, the magnitude of the incidence of many of these diseases may be either lower or higher in organic systems due to different management practices and the standards defined for organic milk production that, for example, prohibit the routine use of conventional medicines and require the feeding of high-forage diets. In relation to different systems, it is important to note that contrary to a common assumption, good welfare does not necessarily occur with more extensive systems. The type of organic system (self-sufficient, purchased-feed) also has the potential to have a major influence on the incidence of health problems and the reproductive status of organic dairy herds. Health status is also influenced by environmental and welfare factors, including the method of rearing replacement animals, type of housing and the geographical and climatic conditions of individual farms. Overall, this review identifies where conflicts arise between current practice and the organic principles and standards, and aims to provide suggestions to bring about further improvement in organic dairy health and welfare.

One hundred and ninety-four lactating British Friesian cows were used over a 2-year period to determine the effects of mixing diet ingredients on dry-matter (D.M.) intake, animal performance, digestibility coefficients, rumen fermentation and efficiency of food utilization. Four treatments were imposed in both years and were complete diet and separate ingredients at ad libitum and restricted levels of feeding.In Expt 1 a complete diet at ad libitum and restricted levels of feeding was compared with separate ingredients. The diet consisted of 60 % concentrates and 40 % forage and contained 20, 20, 10 and 50 % on a D .M. basis of maize silage, lucerne silage, dried sugarbeet pulp and dairy compound, respectively. Method and level of feeding were the same in Expt 2; however, the diet in the 2nd year consisted of 50 % concentrates (40 % dairy compound, 10% dried sugar-beet pulp) and 50% grass silage.In Expt 1 cows fed the complete diet ad libitum consumed 16-5 kg D.M./day which was significantly more than the 14-3 kg/day consumed by those offered the separate ingredients ad libitum. Intakes in Expt 2 were not significantly affected by method of feeding. Much of the difference in Expt 1 was attributed to the fact that many cows rejected lucerne silage when fed in an unmixed form and therefore to keep the concentrate to forage ratio constant other diet ingredients were reduced proportionately.Mixing diet ingredients did not significantly affect milk yields, which were for the complete diet ad libitum and restricted and the separate ingredients ad libitum and restricted 22-2, 22-2; 22-1 and 20-7 kg/day in Expt 1 and 23-6, 20-8; 24-2 and 21-5 kg/ day in Expt 2, respectively. In Expt 1 when the concentrate to forage ratio was 60:40, cows fed the complete diet ad libitum produced milk with a significantly higher milk fat concentration (39-2 g/kg) than those fed the separate ingredients (31-6 g/kg). Similar effects were not recorded in Expt 2 when the concentrate to forage ratio had been reduced to 50:50. Changes in milk protein concentration were more closely related to changes in intake rather than method of feeding. Mixing diet ingredients tended to decrease live-weight loss in early lactation and accelerate live-weight gain in midlactation.In vivo digestibility coefficients determined in lactating dairy cows showed that in Expt 1 the D.M. and organic-matter digestibility coefficients for the complete diets fed ad libitum (0-689 and 0-713) were lower than those recorded (0-712 and 0-732) for the unmixed diet ad libitum. Although the digestibility coefficient of the acid-detergent fibre of the complete diet was markedly higher at 0-519 compared with 0-478 for the separate ingredients, the difference was not significant. In Expt 2 the only difference in digestibility coefficients was that for nitrogen, which for the complete diet was significantly higher than that of the separate ingredients at both levels of feeding.At an ad libitum level of feoding in Expt 1, the molar proportions of acetate and butyrate were 620 and 11...