Effect of season and environmental control on mortality and feed conversion of pigs

Data (including 97 piggeries and 534 fattening periods from 1978 to 1982) originated from contract farming and were put at our disposal by the Belgian Farmers' Association (Belgische Boerenbond). Within the limitations of our material, the expected favourable effect of heating on feed conversion ratio of growing pigs, but not on mortality rate, could be shown. The feed conversion ratio in mechanically ventilated piggeries was higher than that obtained using natural ventilation.     

Effect of ascorbic acid on the mortality of Leghorn-type chickens due to overheating

Leghorn-type chickens in a relatively low-stress environment were fed diets containing 0 to 1100 mg of ascorbic acid (AA)/kg for 1 day before they were subjected to overheating. As the dose of AA increased from 0 to 330 mg/kg, there was decreasing mortality from 40% to 0%. As the dose of AA was increased further, there was an increase in mortality.     

高温季节保持猪高繁殖性能几项措施

近年来,随着全球气候变暖,辽宁省大部分地区夏季出现持续高温天气,对一些工厂化猪场猪的繁殖性能带来了很大的影响。笔者对营口市盖州、大石桥、老边几个万头工厂化猪场2000年至2004年夏季（6-8月）猪的繁殖成绩资料进行了调查统计,结果表明,在7、8两月接受交配的母猪中未能分娩的比例比10月至来年5月交配母猪的不分娩率（15％-10％）高出10％。在此期间母猪产后产道感染引起的高烧无乳发病率明显增多。     

Conception of female rats and litter mortality due to Mn-deficiency

Sexually mature, female rats were fed an Mn-deficient (1.0 ppm) diet on saccharose/casein basis and studied for their reproductive behaviour. Cycle disorders as sometimes described of females depleted over a longer period, were not observed in any case. Although the experimental animals showed a normal estrus, only 50% of the rats conceived. The rats that had become pregnant produced litters of 2 to 11 animals born alive. However, their mortality was 80%. They died either immediately after birth or during the first days post partum.     

高温季节要加强防治＂白口仔＂蚕病

阴雨季节刚刚结束,强烈的阳光普照南粤大地,又到了高温多湿的养蚕季节。笔者最近在阳春合水、岗尾等镇的调查发现,很多蚕农反映养蚕过程中出现大小蚕,实际上是一种俗称“白口仔”的病毒病。     

Urban cats: characteristics and estimation of mortality due to motor vehicles

The present study was undertaken to characterize and estimate cat mortality caused by motor vehicles in Baltimore, Md. Analysis of Municipal Animal Shelter records revealed that the number of dead cats annually removed from Baltimore streets averaged 2,721 over 3 years. The number of cats removed per year was notably constant (range 2,621 to 2,917), with a consistently greater number of animals being picked up during summer months. A map of the location of 634 dead cats removed from city streets showed that areas of highest cat mortality were associated with areas of highest human population density. This map was used to stratify Baltimore into areas of high, medium, and low cat mortality for subsequent stratified random placement of tagged dead cats for the mark-recapture study. One hundred fifteen tagged dead cats were placed on city streets during the course of 1 year, and 50.5% were retrieved by the Municipal Animal Shelter. We estimate over 5,000 free-ranging cats are killed by automobiles/year in Baltimore. Analysis of 212 dead cats removed from city streets showed that the majority were male (63%) and that most animals were sexually intact (90%). At least 20% of the dead animals was previously owned, and few kittens or juvenile cats were found in the sample.     

Effect of density and season on stress and behaviour in broiler breeder hens

1. We examined the effect of density (5, 7, 9 and 11 birds/m2) and season (summerand winter; different hens each season) on stress and behaviour in two flocks of 64 broiler breeder females divided among 8 pens. 2. The hens, approximately the same age and body mass in each season, were maintained on hard-packed ground, without litter, in an open-sided chicken house and were offered the same amount of food each season. 3. Mean house max/min temperatures varied between 18 and 33 degrees C in summer and 7 and 17 degrees C in winter. Mean relative humidity in summer varied between 68% at 08:00 h and 42% at 14:00 h and in winter was 64% at 08:00 h and 47% at 14:00 h. 4. No difference was found in heterophil:lymphocyte ratios among densities and between seasons; however, basophil numbers were higher in winter than in summer indicating prolonged stress in winter. 5. Stereotyped pecking increased with an increase in density and was higher in winter than in summer. Pecking on the ground was higher in winter, but was not affected by density. 6. In summer the hens spent more time lying and eating than in winter, whereas in winter the hens spent more time walking, preening and drinking than in summer. They spent the same amount of time standing in both seasons. None of these behaviours was density dependent. 7. We conclude that season had more of an effect than density on stress and behaviour in broiler breeder hens under the conditions of our study.     

Observations on the patterns of embryonic mortality over the laying season of pheasants.

1. Embryonic mortality of domestic pheasant (Phasianus colchinus) eggs was recorded for a 10-week laying season for two groups of laying hens maintained under mating ratios of 8:1 and 12:1 (females:males). 2. Mating ratio had no significant effect on embryonic mortality between 1 and 4 or 5 and 20 d but values for these categories doubled as the laying season progressed, both rising to 8% to 9% of fertile eggs. 3. Higher embryonic mortality was observed between 21 and 25 d for the eggs from the 8:1 mating ratio (14.5% of fertile eggs compared with 12.1%) but this was unaffected by week of setting. 4. Reasons for these patterns of embryonic mortality were not clear and further research is needed to determine the factors affecting embryonic mortality in pheasants.     

Ranavirus-associated mass mortality in wild amphibians, the Netherlands, 2010: a first report

In 2010, a mass die-off of over 1000 wild water frogs (Pelophylax spp.) and at least 10 common newts (Lissotriton vulgaris) occurred in a pond in The Netherlands. Haemorrhagic disease with hepatomegaly and splenomegaly was evident. Microscopically, multiple organs presented cells with multifocal intracytoplasmic inclusion bodies, in which ranavirus-like particles were demonstrated ultrastructurally. All specimens examined tested positive for ranavirus by PCR. The sequence obtained showed a 100% identity with the one deposited for common midwife toad virus (CMTV). This is the first report of ranavirus-associated mortality in wild amphibian populations in The Netherlands. It is also the first time CMTV or a CMTV-like virus has been reported in these two species in the adult stage and outside of Spain.     

Effects of season and lower ambient temperature on the structure of the sweat glands in anhidrotic horses

Histological studies of the sweat glands of anhidrotic horses in the Hong Kong summer and under conditions of reduced thermal stress, both natural and controlled, were undertaken to determine if glandular regeneration occurs. Clinical data were collected for comparison with the histological results in each instance. Horses were assigned to one of three categories on the basis of the resulting change in the number of thin glandular profiles in a cooler environment. Group 1, which was classed as normal, had a low initial value, which was maintained. Group 2, typical of mild and moderately affected animals, had a high initial value, which fell markedly after as little as six weeks in the cool environment. Animals in Group 3, classed as severely affected, had a high initial value which remained high even after prolonged exposure to the cool environment. Light microscopical examination of the sweat glands in the heat, and after six weeks in a cool environment, provided a means of predicting the degree of anhidrotic severity and the potential for recovery in a cool climate. This was superior to clinical observation, although a diagnostic test based on glandular function is still required.     

Effect of breeder age and breeding season on egg production and incubation in farmed ostriches

(1) This research was carried out to investigate changes in egg production and hatchability as influenced by age and breeding season of 10 trios (two females, one male) of ostrich (Struthio camellus) during 1998 to 2002. (2) Breeding season affected number of eggs laid per female per season, average egg weight, length of laying period and clutch sequence. (3) The number of eggs laid per female per season was 25 in the first breeding season and 57 by the fifth breeding season. The laying period lasted 169 d in the first season whereas it was 210 d by the fifth season. The breeding season became longer year by year. (4) The number of clutches was two in the first season, three in the second and 4 in the later breeding seasons: the mean interval between cycles was 9 to 10.6 d and the mean number of eggs in one cycle varied from 12 to 14.4. (5) The breeding season affected the hatchability of fertile eggs, chick weight at hatching, hatchability of total eggs, fertility, malpositioned embryos, deformed chicks and assisted chicks during hatching. The first 4 variables increased and the last three decreased, with each breeding season. (6) Weight loss of eggs and length of incubation were unaffected by the breeding season. Hatchability which was 64.3% in the first season increased progressively and reached 73.1% in the fifth breeding season.     

温度对蜂蜜淀粉酶值和羟甲基糠醛相关指标的影响

淀粉酶值和羟甲基糠醛是判断蜂蜜质量的重要指标,淀粉酶值和羟甲基糠醛随着温度的升高时间的延长会发生一些较大的变化。淀粉酶值随着加热温度的升高、时间的延长呈下降的趋势,而羟甲基糠醛则随着加热温度的升高、时间的延长呈上升趋势,而且温度越高,上升速率越大。国家标准GB18796—2005规定淀粉酶值小于4和羟甲基糠醛含量大于40mg／kg的蜂蜜属于不合格产品,因此在生产加工和储存的过程中都应控制好温度及时间,以保证产品的质量,温度应控制在80℃以下。     

Effect of dry season supplementation of Sanga cattle in Zambia

Supplementation of lactating Sanga cows in central Zambia with low cost crop residues and urea-mineral licks resulted in significant increases in milk offtake (79%), total daily milk (86%), and daily liveweight gain of their calves (86%). At 1988 market prices the value of the additional milk (ZK54.00) and of liveweight of both cow and calf (ZK189.00) over the 13 weeks exceeded the estimated costs of inputs by ZK180.00.