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1.
D Schams F Graf J Meyer B Graule M Mauthner C Wollny 《Journal of animal science》1991,69(4):1583-1592
Twelve second-lactation Deutsches Fleckvieh cows, (FV, a dual-purpose breed) and 12 German Black and White (BW, a dairy breed) were used to evaluate similarities and differences in the response to a prolonged-release formulation of sometribove (N-methionyl bovine somatotropin, bST). Cows were milked twice daily and fed a basic diet (70% corn silage, 30% alfalfa hay) ad libitum plus 1 kg of concentrate. Additionally, concentrates and supplements were offered at the rate of 1 kg for each 22 kg of milk produced above 12 kg/d. Six cows of each breed were treated s.c. with 500 mg of sometribove at 14-d intervals from wk 9 to 29 postpartum (pp). Blood was collected by jugular vein puncture once weekly from wk 7 to 33 pp and daily for 14 d after the first and last (11th) injection of bST. Somatotropin (ST), insulin-like growth factor I (IGF-I), insulin, thyroid hormones, nonesterified fatty acids (NEFA), liver enzymes, and blood metabolites were evaluated. During bST treatment, plasma ST increased significantly on d 7 in both breeds and then decreased on d 14 after injection. Plasma IGF-I was positively correlated with ST. Plasma NEFA were high on d 7 and decreased on d 14. In response to bST, the average milk yield increased for FV and BW cows by 5.1 kg/d (29.7%) and 5.0 kg/d (28%), respectively, and 4% fat-corrected milk (FCM) increased by 5.0 kg/d (28%) and 5.3 kg/d (19.9%), respectively. Milk content of fat, protein, lactose, number of somatic cells, and body weight were similar across treatments.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
2.
To be successful, initiatives to improve smallholder’s goat production should directly address the needs and objectives of
the keepers while promoting rational use of local genetic resources. This paper identifies the objectives, constraints and
needs of goat farmers in southern Benin and discusses their relevance to the development of improvement programmes. Between
November and December 2005, structured questionnaires, focus group discussions and participant observation were used to collect
information from 38 goat farmers in two selected locations. Goats were kept mainly for sale whenever cash was needed. Traits
related to reproduction, to behaviour, to health and to meat production were considered equally important and were ranked
very highly by goat keepers. Increased net income per flock through increased number of marketable animals is the derived
breeding objective from the trait analysis. Disease outbreaks resulting in high mortality, poor housing, and feed shortages
were, in descending order, the most important problems. It was concluded that the development of initiatives to improve management
practices is an overriding priority. It will lead to increases in productivity in the short term and foster farmers’ participation
in the development of long-term improvement strategies, which should include selection and controlled mating. 相似文献
3.
Local chicken production system in Malawi: Household flock structure,dynamics, management and health 总被引：1，自引：1，他引：0
Household flocks of scavenging chickens were monitored from August 2002 to August 2003 in 27 villages in Lilongwe, Malawi.
The objective was to evaluate the local chicken production system by investigating flock structure, utilization, management
and constraints. Farmers and researchers jointly obtained data on household flocks. Mean flock size was 12.9, with a range
of 1–61 chickens. The flock dynamics of chickens over 8 weeks old constituted 91% migrating out of flocks and 9% into the
flocks. Primary functions based on flock dynamics were, in order of importance, household consumption, participation in socio-cultural
ceremonies, selling, exchanging breeding stock and gifts. Of the flock exits, 43.9% were due to losses from diseases, predation
and theft. Most flocks (85%) were housed in human dwelling units. Scavenging was the main source of feed. The majority (77.6%)
of farmers supplemented their chickens erratically with energy-rich feeds, mostly maize bran. Most supplementation took place
during the cold-dry season. Village chicken production offers diverse functional outputs but faces animal health (diseases,
parasites, predation) and management (feeding) constraints, which require an integrated intervention approach at community
and household level. 相似文献
4.
Choice of breeding stock,preference of production traits and culling criteria of village chickens among Zimbabwe agro-ecological zones 总被引：3，自引：3，他引：0
Muchadeyi FC Wollny CB Eding H Weigend S Simianer H 《Tropical animal health and production》2009,41(3):403-412
Free ranging chickens reared by smallholder farmers represent genetic diversity suited for particular environments and shaped
by the socio-economic and cultural values of the farming systems. This study sought to investigate the existence of chicken
strains and evaluate the breeding goals and strategies used by village chicken farmers in Zimbabwe. A semi-structured questionnaire
was administered to 97, 56, 70, 104 and 37 households randomly selected from five agro-ecological-zones I-V, respectively.
Fifteen chicken strains mostly defined by morphological traits were reported in the five eco-zones. Production criteria such
as body size, and fertility were highly ranked (ranging from 1.3 – 2.6) by farmers across all the eco-zones, while cultural
traits were the least preferred production traits. As a common breeding practice, farmers chose the type of hens and cocks
to retain for breeding purposes and these randomly mixed and mated with others from community flocks. Chicken body size was
ranked the major determinant in choosing breeding animals followed by mothering ability, and fertility. More households culled
chickens associated with poor reproductive performance, poor growth rates and those intolerant to disease pathogens. The focus
on many negatively correlated production traits and the absence of farmer records compromises breeding strategies in these
production systems. 相似文献
5.
6.
Brown SS Ryerson TB Wollny AG Brock CA Peltier R Sullivan AP Weber RJ Dubé WP Trainer M Meagher JF Fehsenfeld FC Ravishankara AR 《Science (New York, N.Y.)》2006,311(5757):67-70
Nitrogen oxides in the lower troposphere catalyze the photochemical production of ozone (O3) pollution during the day but react to form nitric acid, oxidize hydrocarbons, and remove O3 at night. A key nocturnal reaction is the heterogeneous hydrolysis of dinitrogen pentoxide, N2O5. We report aircraft measurements of NO3 and N2O5, which show that the N2O5 uptake coefficient, g(N2O5), on aerosol particles is highly variable and depends strongly on aerosol composition, particularly sulfate content. The results have implications for the quantification of regional-scale O3 production and suggest a stronger interaction between anthropogenic sulfur and nitrogen oxide emissions than previously recognized. 相似文献
7.
Variation in village chicken production systems among agro-ecological zones of Zimbabwe 总被引：1，自引：1，他引：0
Muchadeyi FC Wollny CB Eding H Weigend S Makuza SM Simianer H 《Tropical animal health and production》2007,39(6):453-461
The degree to which village chickens are integrated in the smallholder farming systems differs depending on the socio-economic,
cultural and biological factors within each system. The objective of this study was to characterise the village chicken farming
systems and identify possible threats to, and opportunities for, local chickens in the agro-ecological zones of Zimbabwe.
A pre-tested questionnaire was administered to households randomly selected from five districts, Risitu (n = 97), Hurungwe
(n = 56), Gutu (n = 77), Gokwe-South (n = 104) and Beitbridge (n = 37) in eco-zones I–V, respectively. Age of head of household
averaged 47 years (SD = 14.3). Land holdings per household averaged 4.82 ha (SD = 3.6). Overall, 17.7 percent of the households
ranked livestock as the major source of income compared to 70.8 percent who ranked crops as the main contributor. Chicken
flock size averaged 16.7 (SD = 12.4), and the highest flock sizes were observed in eco-zones I and IV. Households owning cattle,
goats and other livestock assigned less important ranks to chickens. Chickens were used mainly for the provision of meat and
eggs whilst the use of chicken feathers and investment were uncommon practises. Results indicate that more support is necessary
for village chickens in the non-cropping regions of the country. 相似文献
8.
Characterization of local chicken production systems and their potential under different levels of management practice in Jordan 总被引：2，自引：2，他引：0
This study aimed to characterize the local chickens and their production systems and to investigate the opportunities for
improvement. The study was carried out in 18 villages in northern Jordan with the participation of 120 households. Data were
collected by individual interviews and surveys supported with structured questionnaires. A scoring system was developed to
study the effect of different levels of management on chicken performance. The main reasons for keep local chickens were egg
production and generation of income. The main features of the production systems were improper housing and inadequate hygiene.
Newcastle disease, predators, and parasites were the main causes of flock losses. Purchasing rate was controlled by the chickens’
phenotype, sex and age, and by season of year. The average flock size was 41.6 (±32.9) chickens per household, with a hen:cock
ratio of 6.4:1. The average effective population size was 15.35, which indicated a high rate of inbreeding (5.52%). The main
selection criterion adopted by farmers was egg production. There were positive significant correlations (p < 0.001) between management level and chickens’ performance. Hatchability, survivability, flock size, number of clutches,
egg weight and egg mass were the major parameters that improved significantly with improvement in management level. Local
chickens fulfil significant functions in the livelihood of rural smallholders; however, many constraints affected the efficiency
of the production systems. Solutions should start with improving the management practices and establishing an effective breeding
system. 相似文献
9.
M. Faber T. Wollny M. Schlegel K. M. Wanka J. Thiel C. Frank D. Rimek R. G. Ulrich K. Stark 《Zoonoses and public health》2013,60(8):549-554
In 2010, the highest annual number of human Puumala virus (PUUV) infections was reported in Germany since hantavirus surveillance started in 2001. The increase in annual case numbers was especially marked in western Thuringia. We combined results of case‐based hantavirus surveillance in humans and serological and molecular investigations in the rodent reservoir to describe the epidemiological situation and to identify the putative outbreak strain. A 5‐fold increase in notified hantavirus cases compared to the previous annual maximum was observed in western Thuringia in 2010. Disease incidence varied tremendously within a small geographical area with case patients' places of residence clustering around beech‐dominated broad leaf forest patches. Investigations in the rodent reservoir revealed a novel Puumala virus (PUUV) subtype, which is clearly distinct from strains collected in other PUUV endemic regions of Germany. It can be assumed that in regions in western Thuringia where hantavirus cases occurred in 2010 or previous outbreak years, PUUV has been present in the environment for a long time. Further studies are needed to elucidate the population dynamics and hantavirus prevalence of the rodent reservoir and driving ecological factors. 相似文献
10.
We conducted a cross-sectional study from December 2004 to February 2005 and from June 2005 to August 2005. The study aimed to determine the prevalence of gastrointestinal and tracheal helminthes among local chickens in northern Jordan. A total of 208 male and female local scavenging chickens were selected randomly. We examined the trachea and gastrointestinal tract of each bird for the presence of helminthes. We recovered three nematode and eight cestode species. No trematodes were found. One hundred and fifty-two birds (73.1%) (95% CI: 67, 79) were infected. The prevalences of different species were as follows: Ascaridia galli female 28%, male 43%; Capillaria obsignata 0.5%; Heterakis gallinarum 33%; Amoebotaenia cuneata 4.3%; Choanotaenia infundibulum female 23%, male 13%; Davainea proglottina 1.4%; Hymenolepsis cantaniana 11%; Hymenolepsis carioca female 35%, male 24%; Raillietina cesticillius female 5%, male 11%; Raillietina echinobothrida 16%; and Raillietina tetragona 18%. The prevalences of A. galli and R. cesticillus were higher in male than female hosts while those of C. infundibulum and H. carioca were higher in females. The median worm burden was 7 (range 0–168) worms per chicken. 相似文献