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Pre-weaning animals exit a flock through death induced by various reasons, causing significant economic losses to the goat producers. In this study, we investigated the survival from birth to weaning of Sirohi goat kids within framework of the survival analysis. Kid records were accessed from 1997 to 2017, with the information on 4417 pre-weaning animals of farmed Sirohi goat native to the Rajasthan State of India. A multivariable Cox regression was fitted to the data after checking the assumptions of regression. The explanatory variables were sex, type of birth, season of birth, birthweight, doe weight at kidding and year of birth. Model selection eliminated doe weight from the model, and sex, type of birth, season of birth, birthweight and year of birth were retained in the model. With model calibration also, these five covariates were retained in the model. The mortality on the first day after birth was 0.3%, constituting 3.5% of all pre-weaning mortality. The mortality until the end of weaning period was 7.8%. Regression analysis revealed that the higher birthweight at kidding was associated with reduced hazard of death among the kids. Male kids had higher hazards of death compared with female kids. The single-born kids had lower risks of death compared with twin-born kids after accounting for heterogeneity. The winter season had a very high adverse effect on the survival of the kids. With each passing year, risks of death decreased. The results of this study indicate that better survival of kids can be achieved by controlling both environmental and animal-related factors.  相似文献   

3.
《Small Ruminant Research》2003,47(2):133-143
This study attempts to describe the semi-extensive goat farming sector in Andalusia (south of Spain) and to establish characteristics. Eighty-nine goat farmers were surveyed in three areas of this region. The survey examined all aspects of the systems, from socio-economy to management. A multivariate analysis (multiple correspondence and cluster) was used to determine the different farm characteristics. Most of the goat farms studied are single-worker or family managed. The farmers lack training and are elderly, so that continuity of the activity is not assured, although newcomers are usually young. All the farms have some area in ownership, although the farms most specialized in dairy goat products are the smallest in both ownership and total area. The roads are generally in good condition, except on farms with little land, situated in areas of the sierra. Machine-milking installations, closely related to the presence of infrastructures and of goats with a dairy tendency, are generally lacking, (this aspect is improving day by day). Artificial nursing is less generalized than machine-milking. Farms specializing in milk production, whose main activity is dairy goat farming, have dairy specialized breed or crossbred (milk and meat) goats. Feeding depends largely on grazing, with little area being cultivated to produce feed for the goats. Little distinction is made for the production level. Olive or acorn tree branches (Quercus ilex spp.) are used as feedstuff, depending on the types of tree predominating in the area. Five farm types were established, the differences depending on 14 variables of socio-economic aspects, level of production, infrastructure and installations, and feeding. Generated information from this study entails an advance into knowledge of goat farming systems in the Mediterranean area (where little information is generated). The relevance of this study is important since Andalusia has 40% of goats in Spain that produce more than half of the total goat milk in the country, which points out the socio-economical importance for most depressed areas in the region. This work supposes previous steps for improving the semi-extensive goat farming sector. From a methodological point of view, the discussion on variable types and utility establishes farm type characteristics.  相似文献   

4.
A study was undertaken to look into the reproductive performance of female Dwarf goats reared under traditional conditions at NIAB Farm, Faisalabad, Pakistan. The serum progesterone profile was used to monitor various reproductive parameters (length of postpartum period, resumption of cyclicity, gestation period, prepartum period, parturition) in two lots of goats. Litter size, birth weight of kids and kidding interval were also observed. Most of the animals conceived within 15-59 days of postpartum period. All the does conceived at first or second estrus. During gestation period, higher levels of progesterone were maintained with wide variations falling in the range of 3-13 ng ml(-1). However, a few days before parturition a decline was noticed at 6+/-0.9 days and it reached to the basal level of 0.1 ng ml(-1) after the completion of parturition process. The length of gestation period was found to be 145.8+/-5 days in the first lot and 145.2+/-4 days in the second lot. A very short kidding interval (203.7+/-46 days) and considerably bigger litter size (1.8+/-0.8) was observed. All the parturitions were normal and a considerable weight gain (8.2+/-0.3 kg) of mothers was recorded during pregnancy. The initial birth weight of kids was averaged as 2.1+/-0.5 kg in the first and 1.6+/-0.2 kg in the second lot. It was concluded that Dwarf goat has short gestation length, postpartum period and kidding interval along with multiple births being common. Due to these factors, its reproductive efficiency can be exploited for efficient goat meat production.  相似文献   

5.
The energy supplied by the high-forage diets used in organic farming may be insufficient to meet the requirements of dairy cattle. However, few studies have considered this problem. The present study aimed to analyze the composition of the diets and the nutritional status (focusing on the energy–protein balance of the diets) of dairy cattle reared on organic farms in northern Spain, which are similar to other organic farming systems in temperate regions. Exhaustive information about diets was obtained from organic (ORG) and representative conventional grazing (GRZ) and conventional no-grazing (CNG) farms. Samples of feed from the respective farms were analyzed to determine the composition. Overall, the diets used on the ORG farms were very different from those used on the CNG farms, although the difference was not as evident for GRZ. The CNG farms were characterized by a higher total dry matter intake with a high proportion of concentrate feed, maize silage and forage silage. By contrast, on ORG and GRZ farms, the forage, pasture and fibre intake were the most important variables. The ration used on ORG farms contained a significantly higher percentage of ADF and lower organic matter (OM) content than the rations used in both of the conventional farming systems, indicating that the diets in the former were less digestible. Although the protein concentration in the diets used on the grazing farms (ORG and GRZ) was higher than those used on CNG farms, the protein intake was similar. The results indicated an imbalance between energy and protein due to the low level of energy provided by the ORG diets, suggesting that more microbial protein could be synthesized from the available rumen-degraded dietary nitrogen if rumen-fermentable OM was not limiting. The imbalance between energy and protein led to a reduced amount of total digestible protein reaching the intestine and a lower milk yield per kilogram of CP intake on the ORG farms. In order to improve the protein use efficiency and consequently to reduce the loss of nitrogen to the environment, organic farming should aim to increase the energy content of cattle diets by improving forage quality and formulating rations with more balanced combinations of forage and grain.  相似文献   

6.
Organic farming conserves natural resources, promotes biodiversity, guarantees animal welfare and obtains healthy products from raw materials through natural processes. In order to evaluate possibilities of increasing organic animal production, this study proposes a farm-scale multicriteria method for assessing the conversion of dairy goat systems to the organic model. In addition, a case study in the Northern Sierra of Seville, southern Spain, is analysed. A consensus of expert opinions and a field survey are used to validate a list of potential indicators and issues for assessing the conversion, which consider not only the European Community regulations for organic livestock farming, but also agroecological principles. As a result, the method includes 56 variables integrated in nine indicators: Nutritional management, Sustainable pasture management, Soil fertility and contamination, Weed and pest control, Disease prevention, Breeds and reproduction, Animal welfare, Food safety and Marketing and management. The nine indicators are finally integrated in a global index named OLPI (Organic Livestock Proximity Index). Application of the method to a case study with 24 goat farms reveals an OLPI value of 46.5% for dairy goat farms located in mountain areas of southern Spain. The aspects that differ most from the agroecological model include soil management, animal nutrition and product marketing. Results of the case study indicate that the proposed method is easy to implement and is useful for quantifying the approximation of conventional farms to an organic model.  相似文献   

7.
Maternal behavior in the goat appears at the time of parturition, partly under the activating influence of vaginocervical stimulation. Mothers actively lick their neonate and rapidly establish a selective bond with their kid through olfactory recognition. They also develop visual and acoustic recognition of the kid within 4 h following birth. Acoustic recognition is present at 48 h. The establishment of maternal recognition can be impaired by underfeeding during the second half of pregnancy. There is no indication that the mechanisms controlling the onset of maternal behavior and bonding are different from those reported in sheep, despite the fact that lambs start to follow their mother within a few hours after birth and kids hide for about a week. During lactation, the cues provided by the kid are necessary for the maintenance of maternal responsiveness, but suckling itself does not appear of primary importance. The presence of the kid also modulates the hormonal response to udder stimulation and influences recovery of postpartum sexual activity when kidding (i.e. birthing) takes place in autumn. Finally, the rapid establishment of mutual attachment between mother goats (does) and their kids offers the possibility to investigate an aspect of mother-young affiliation that is not present in many laboratory species.  相似文献   

8.
Studies aimed to assess up to what extent farming and transport previous to slaughtering might affect physiology and meat quality in young goat kids are needed, with the ultimate purpose of promoting practices that minimize stress in these animals. In this regard the effects of on-farm management and transport duration on some physiological responses and meat quality parameters in goat kids were assessed. Two farms representing ‘high’ and ‘low’ welfare-friendly management practices were selected. In total, 32 suckling kids were withdrawn from each farm, transported by road for 2 or 6 h, and then slaughtered. Blood samples were collected both on-farm and in the slaughterhouse, and biochemistry, cell counts and haematocrit were determined. After slaughtering, carcass quality parameters were measured. Longissimus dorsi muscle was dissected and pH, colour parameters, water holding capacity and shear force were measured throughout 8-day ageing period. Results indicate that, regardless its duration, transport caused significant effects on some blood parameters suggesting stress in live animals, like glucose, cortisol or creatine kinase. Despite the marked stress status in animals, this condition was not decisively reflected on L. dorsi quality parameters, but some effects were observed regarding fat cover in carcasses and colour parameters. The results suggest that postmortem changes throughout ageing were more decisive in terms of meat quality than stressful management either on-farm or during transport.  相似文献   

9.
The aim of this study was to analyze the economic viability of producing dairy goat kids fed liquid diets in alternative of goat milk and slaughtered at two different ages. Forty-eight male newborn Saanen and Alpine kids were selected and allocated to four groups using a completely randomized factorial design: goat milk (GM), cow milk (CM), commercial milk replacer (CMR) and fermented cow colostrum (FC). Each group was then divided into two groups: slaughter at 60 and 90 days of age. The animals received Tifton hay and concentrate ad libitum. The values of total costs of liquid and solid feed plus labor, income and average gross margin were calculated. The data were then analyzed using the Monte Carlo techniques with the @Risk 5.5 software, with 1000 iterations of the variables being studied through the model. The kids fed GM and CMR generated negative profitability values when slaughtered at 60 days (US$ −16.4 and US$ −2.17, respectively) and also at 90 days (US$ −30.8 and US$ −0.18, respectively). The risk analysis showed that there is a 98% probability that profitability would be negative when GM is used. In this regard, CM and FC presented low risk when the kids were slaughtered at 60 days (8.5% and 21.2%, respectively) and an even lower risk when animals were slaughtered at 90 days (5.2% and 3.8%, respectively). The kids fed CM and slaughtered at 90 days presented the highest average gross income (US$ 67.88) and also average gross margin (US$ 18.43/animal). For the 60-day rearing regime to be economically viable, the CMR cost should not exceed 11.47% of the animal-selling price. This implies that the replacer cannot cost more than US$ 0.39 and 0.43/kg for the 60- and 90-day feeding regimes, respectively. The sensitivity analysis showed that the variables with the greatest impact on the final model’s results were animal selling price, liquid diet cost, final weight at slaughter and labor. In conclusion, the production of male dairy goat kids can be economically viable when the kids diet consists mainly of either cow milk or fermented colostrum, especially when kids are slaughtered at 90 days of age.  相似文献   

10.
The seasonal workload combined with increased dairy herd sizes and a declining workforce have created social sustainability challenges for pasture-based dairy farms. Effective work organisation can build productive capacity that may have a positive impact on this scenario. Our objective was to develop a framework to characterise and examine the effect of work organisation on the working situations of the people involved in a sample of 55 pasture-based dairy farms in Ireland. We conceptualised that effective work organisation on a dairy farm could be considered as a system that is efficient from a labour input perspective, resulting in a profitable farming system with outcomes of good operator well-being, health and safety, and quality of life. A literature review established efficiency & productivity, flexibility and standardisation as our three characteristics of work organisation. Using data from an existing labour time-use study completed from the 1st February to 30th June 2019, we aimed to test the veracity of these work organisation characteristics in the Irish pasture-based dairy system. Two proxy indicators were selected to represent each of the three work organisation characteristics, and each of the 55 farms were categorised into quartiles based on their ranking for these six indicators (1 = most effective quartile to 4 = least effective quartile). The most and least effective quartiles of farms for work organisation showed similar levels of farm labour input and labour efficiency. Farmers in the most effective work organisation quartile were working 51.2 h/week from February to June compared with 70.0 h/week for farmers in the least effective quartile, which was attributed to later start times, earlier finish times, and more time at non-farm activity. Farms achieving effective work organisation had a labour-efficient system with relatively low farmer working hours. Extension of the work organisation concept to other farms could improve their labour situation and aid in alleviating some of the key quality of life challenges faced by dairy farmers.  相似文献   

11.
Supernumerary Teat Removal Can Be Avoided in Dairy Sheep   总被引:2,自引:0,他引:2  
The aim of this work was to determine whether the removal of supernumerary teats from dairy sheep when they are born is a useful procedure in the farming routine. Ewes were divided into 3 groups according to the number of teats at milking: ewes who were born with 2 teats; ewes who were born with 4 teats and had the 2 supernumerary nipples cut just after birth; and ewes who were born with 4 teats and did not have nipple amputation performed. Removal of supernumerary teats at lambing produced a significant reduction in milk production during the 2 first milking periods (p < .01). There were no differences between ewes with 2 or 4 teats, which suggests that this procedure is not necessary on dairy sheep farms. Because the presence of supernumerary teats is highly heritable, the elimination of this trait could be accomplished through selection methods.  相似文献   

12.
This study analysed the effect of level of nutrition and date of birth (age) on the onset of puberty in Payoya she-kids born in autumn (November) or in winter (February). Two experiments were conducted to examine pubertal events at the onset of puberty. For each date of birth (age), two experimental groups were used, differing on the level of nutrition. Groups were balanced for live weight (LW) and body condition score (BCS). For the first experiment (goat kids born in autumn), 27 Payoya she-kids were used: high-nutrition group (H1, n = 13) and control group (C1, n = 14). For the second experiment (goat kids born in winter), 25 Payoya she-kids were used: high-nutrition group (H2, n = 13) and control group (C2, n = 12). In both experiments, the level of feeding was adjusted weekly according to LW so that the animals would gain about 50 and 100 g per day for C and H groups, respectively. Oestrus was tested daily using young aproned bucks. Ovulation rate was assessed by laparoscopy 7 days after identification of oestrus. Plasma samples were obtained weekly for progesterone assay. LW and BCS were recorded weekly. No effect of nutrition level or birth date (Experiment 1 v. 2) on the date of the first ovarian activity or the first detected oestrus was observed. No effect of nutrition on LW or BCS at the first detected oestrus was observed. Birth date influenced significantly the LW of the animals at the onset of ovarian activity or first oestrus (P < 0.001). Irregular sexual activity was frequently observed before the first oestrus (74.7% and 48.0% of the first reproductive activity was irregular for Experiments 1 and 2, respectively). No effect of nutrition level or birth date on ovulation rate was observed. Ovulation rate at first oestrus was influenced by LW in November-born goat kids (1.06 ± 0.06 v. 1.67 ± 0.21 corpora lutea for LW < 30 and 30 kg, respectively, P < 0.01). These results demonstrate that the age at puberty was very dependent upon the season of birth in Payoya goat kids, and that there could be some benefit in breeding November-born goat kids at a higher LW to obtain a higher prolificacy at the first kidding as a consequence of a higher ovulation rate at puberty.  相似文献   

13.
Water scarcity is among the main challenges making vulnerable the livestock farming systems in drylands. The water footprint (WF) indicator was proposed as a metric to measure the impacts of livestock production on freshwater resources. Therefore, this study aimed to assess water use in five different Tunisian sheep production systems using the Water Footprint Network methodology. The primary data were obtained from 1050 sheep farms located in 13 Tunisian provinces. A multivariate analysis was performed to characterize the different farming systems. A validation step of the WF modeled values of sheep meat was conducted in 12 sheep farms belonging to two different farming systems. This was done through year-round monitoring of on-farm practices using water metres and recording equipment’s taking into account the direct and indirect water use. The typology analysis came up with five sheep farming systems that are the mixed sheep-cereal (MSC), the agro-sylvo-pastoral (ASP), the agro-pastoral (AP), the extensive agro-pastoral (EAP) and the mixed sheep-olive tree farming systems. The WF of sheep meat produced under the target farming systems ranged from 8654 to 13 056 l/kg live weight. The evaluation of WF of five different sheep production systems figured out that sheep raised under the EAP farming system had the greatest WF per ton of live animal. However, the ASP farming system exhibited the lowest WF. Water used to grow feedstuffs for sheep production accounts for 98% of the total WF of sheep. The green WF accounts for more than 92% of the total WF in all farming systems. Results of monitoring water use at farm scale show that the modeled values of WF are overestimated by an average of 23.3% and 24.1% for the selected farms assigned to the MSC and AP farming systems, respectively. Water use for sheep production is high in most of the Tunisian farms. Therefore, the general assumption that ‘meat production is a driver of water scarcity’ is supported and should be considered as an important focal point in agricultural and water policies. Particular attention should be given to forage crops with low WFs and high contribution to dry matter to provide ration with low WF. The efficient use of green water along the meat value chain is essential to minimize the depletion of blue water resources and to reduce the economic dependency on virtual water through the import of feedstuffs.  相似文献   

14.
A stock of 148 Cryptosporidium parvum DNA extracts from lambs and goat kids selected from a previous study examining the occurrence of Cryptosporidium species and GP60 subtypes in diarrheic lambs and goat kids in northeastern Spain was further characterized by a multilocus fragment typing approach with six mini- and microsatellite loci. Various degrees of polymorphism were seen at all but the MS5 locus, although all markers exhibited two major alleles accounting for more than 75% of isolates. A total of 56 multilocus subtypes (MLTs) from lambs (48 MLTs) and goat kids (11 MLTs) were identified. Individual isolates with mixed MLTs were detected on more than 25% of the farms, but most MLTs (33) were distinctive for individual farms, revealing the endemicity of cryptosporidial infections on sheep and goat farms. Comparison with a previous study in calves in northern Spain using the same six-locus subtyping scheme showed the presence of host-associated alleles, differences in the identity of major alleles, and very little overlap in MLTs between C. parvum isolates from lambs and those from calves (1 MLT) or isolates from lambs and those from goat kids (3 MLTs). The Hunter-Gaston index of the multilocus technique was 0.976 (95% confidence interval [CI], 0.970 to 0.982), which supports its high discriminatory power for strain typing and epidemiological tracking. Population analyses revealed the presence of two host-associated subpopulations showing epidemic clonality among the C. parvum isolates infecting calves and lambs/goat kids, respectively, although evidence of genetic flow between the two subpopulations was also detected.  相似文献   

15.
《Small Ruminant Research》2010,90(2-3):102-109
Organic goat production can be a rewarding livelihood and is gaining popularity. Global organic production has increased significantly annually over the past decade. Industry analysts forecast that demand in many markets will continue to grow at 10–30% per year, with the international organic market expected to grow to a volume of US$ 100 billion in the next decade. Organic dairy has shown stronger growth rates than organic meat production. In certain regions, the rise in organic milk production has increased the range of processed value-added organic milk and dairy products, and demand is out-stripping supply. The basic principles of organic goat production include care, ecology, fairness, and health as stated by the International Federation of Organic Agriculture Movement (IFOAM). Organic goat production can improve animal welfare, protect the environment, and sustain rewarding rural live styles. There are challenges when dealing with organic goat production, especially when one hopes to control intestinal parasites and to achieve adequate nutritional management. Exploring nutritional technology and disease prevention and treatment will eventually improve the production efficiency. There are various regulations in different countries that apply to certify organic foods, and the number of regulations is growing. One of the leading federations in international organic farming is IFOAM. The standards can be certified under IFOAM then can be recognized in many counties around the world. These regulations serve as branding effort, not only to protect the “organic” brand but also to promote it. Future of organic goat production will have to rely on continue search for alternatives in nutrition and disease prevention and control that are environmentally friendly, human health conscientious and animal considerate. Understanding organic goat farming from economic, ecological, and animal welfare perspectives will increase the likelihood of success.  相似文献   

16.
Improving feed efficiency in dairy cattle could result in more profitable and environmentally sustainable dairy production through lowering feed costs and emissions from dairy farming. In addition, beef production based on dairy herds generates fewer greenhouse gas emissions per unit of meat output than beef production from suckler cow systems. Different scenarios were used to assess the profitability of adding traits, excluded from the current selection index for Finnish Ayrshire, to the breeding goal for combined dairy and beef production systems. The additional breeding goal traits were growth traits (average daily gain of animals in the fattening and rearing periods), carcass traits (fat covering, fleshiness and dressing percentage), mature live weight (LW) of cows and residual feed intake (RFI) traits. A breeding scheme was modeled for Finnish Ayrshire under the current market situation in Finland using the deterministic simulation software ZPLAN+. With the economic values derived for the current production system, the inclusion of growth and carcass traits, while preventing LW increase generated the highest improvement in the discounted profit of the breeding program (3.7%), followed by the scenario where all additional traits were included simultaneously (5.1%). The use of a selection index that included growth and carcass traits excluding LW, increased the profit (0.8%), but reduced the benefits resulted from breeding for beef traits together with LW. A moderate decrease in the profit of the breeding program was obtained when adding only LW to the breeding goal (−3.1%), whereas, adding only RFI traits to the breeding goal resulted in a minor increase in the profit (1.4%). Including beef traits with LW in the breeding goal showed to be the most potential option to improve the profitability of the combined dairy and beef production systems and would also enable a higher rate of self-sufficiency in beef. When considering feed efficiency related traits, the inclusion of LW traits in the breeding goal that includes growth and carcass traits could be more profitable than the inclusion of RFI, because the marginal costs of measuring LW can be expected to be lower than for RFI and it is readily available for selection. In addition, before RFI can be implemented as a breeding objective, the genetic correlations between RFI and other breeding goal traits estimated for the studied population as well as information on the most suitable indicator traits for RFI are needed to assess more carefully the consequences of selecting for RFI.  相似文献   

17.
The resistance of gastro-intestinal nematodes of small ruminants (sheep and goat) to benzimidazole anthelmintic drugs seems to be linked primarily to a single mutation in the isotype 1 beta-tubulin gene. This study was carried out to investigate the origin and diversity of benzimidazole-resistance alleles in trichostrongylid nematodes. We sequenced a 550 bp fragment of the isotype 1 beta-tubulin gene from several benzimidazole-resistant Teladorsagia circumcincta populations isolated from dairy goat farms in the central and south-western France. We also sequenced the same beta-tubulin fragment from Trichostrongylus colubriformis and Haemonchus contortus populations in south-western France. We found eight benzimidazole-resistance alleles in all T. circumcincta populations studied, six in H. contortus populations, and only one in T. colubriformis populations. In most cases, only one benzimidazole-resistance allele was present in T. circumcincta and H. contortus populations, but two alleles were found in a fewer number of them. Some T. circumcincta populations shared the same benzimidazole-resistance allele whereas some others had a specific benzimidazole-resistance allele. Similar findings were obtained for H. contortus. As no parasites are introduced once the flock of dairy goat farms has been constituted, these data indicate for the three studied species that rare pre-existing benzimidazole-resistance alleles already present before the isolation of populations had been selected. On the other hand, the fact that some benzimidazole-resistance alleles were specific to one population of T. circumcincta or H. contortus, seems to be in agreement with the hypothesis of the selection of spontaneous mutations. Thus, the origin of benzimidazole-resistance alleles in trichostrongylid nematodes seems to involve primarily the selection of rare alleles and possibly of spontaneous mutations.  相似文献   

18.
The calving interval (CI) can potentially impact the economic results of dairy farms. This study highlighted the most profitable CI and innovated by describing this optimum as a function of the feeding system of the farm. On-farm data were used to represent real farm conditions. A total of 1832 accounts of farms recorded from 2007 to 2014 provided economic, technical and feeding information per herd and per year. A multiple correspondence analysis created four feeding groups: extensive, low intensive, intensive and very intensive herds. The gross margin and some of its components were corrected to account for the effect of factors external to the farm, such as the market, biological status, etc. Then the corrected gross margin (cGMc) and its components were modelled by CI parameters in each feeding system by use of GLM. The relationship between cGMc and the proportion of cows with CI<380 days in each feeding group showed that keeping most of the cows in the herd with CI near to 1 year was not profitable for most farms (for the very intensive farms there was no effect of the proportion). Moreover, a low proportion of cows (0% to 20%) with a near-to-1-year CI was not profitable for the extensive and low intensive farms. Extending the proportion of cows with CI beyond 459 days until 635 days (i.e. data limitation) caused no significant economic loss for the extensive and low intensive farms, but was not profitable for the intensive and very intensive farms. Variations of the milk and feeding components explained mainly these significant differences of gross margin. A link between the feeding system and persistency, perceptible in the milk production and CI shown by the herd, could explain the different relationships observed between the extent of CI and the economic results in the feeding groups. This herd-level study tended to show different economic optima of CI as a function of the feeding system. A cow-level study would specify these tendencies to give CI objectives to dairy breeders as a function of their farm characteristics.  相似文献   

19.
Intensification and specialisation of agriculture in developed countries enabled productivity to be improved but had detrimental impacts on the environment and threatened the economic viability of a huge number of farms. The combination of livestock and crops, which was very common in the past, is assumed to be a viable alternative to specialised livestock or cropping systems. Mixed crop-livestock systems can improve nutrient cycling while reducing chemical inputs and generate economies of scope at farm level. Most assumptions underlying these views are based on theoretical and experimental evidence. Very few assessments of their environmental and economic advantages have nevertheless been undertaken in real-world farming conditions. In this paper, we present a comparative assessment of the environmental and economic performances of mixed crop-livestock farms v. specialised farms among the farm population of the French ‘Coteaux de Gascogne’. In this hilly region, half of the farms currently use a mixed crop-livestock system including beef cattle and cash crops, the remaining farms being specialised in either crops or cattle. Data were collected through an exhaustive survey of farms located in our study area. The economic performances of farming systems were assessed on 48 farms on the basis of (i) overall gross margin, (ii) production costs and (iii) analysis of the sensitivity of gross margins to fluctuations in the price of inputs and outputs. The environmental dimension was analysed through (i) characterisation of farmers’ crop management practices, (ii) analysis of farm land use diversity and (iii) nitrogen farm-gate balance. Local mixed crop-livestock farms did not have significantly higher overall gross margins than specialised farms but were less sensitive than dairy and crop farms to fluctuations in the price of inputs and outputs considered. Mixed crop-livestock farms had lower costs than crop farms, while beef farms had the lowest costs as they are grass-based systems. Concerning crop management practices, our results revealed an intensification gradient from low to high input farming systems. Beyond some general trends, a wide range of management practices and levels of intensification were observed among farms with a similar production system. Mixed crop-livestock farms were very heterogeneous with respect to the use of inputs. Nevertheless, our study revealed a lower potential for nitrogen pollution in mixed crop-livestock and beef production systems than in dairy and crop farming systems. Even if a wide variability exists within system, mixed crop-livestock systems appear to be a way for an environmental and economical sustainable agriculture.  相似文献   

20.
A total of 587 kidding records of West African Dwarf (WAD) goats over 10 years (1982–1991) were used. Mean kidding interval and litter size at birth were 275.68 ± 6.08 days and 1.79 ± 0.05 kids, respectively. Effects of parity, season and year of birth were significant (P < 0.05) for kidding interval. Parity also had significant effect (P < 0.05) on litter size at birth. Heritability estimates of 0.35 ± 0.05 and 0.32 ± 0.07 were obtained from sire and sire-dam groups, respectively, for litter size at birth. Heritability estimate for kidding interval was 0.03 ± 0.01 from sire-dam group. Repeatability estimates of 0.38 ± 0.05 and 0.33 ± 0.03 were obtained for litter size at birth while 0.06 ± 0.04 and 0.04 ± 0.02 were obtained for kidding interval from dam and sire-dam group, respectively. Selection for multiple birth is likely to result in larger litter size while culling of does for long kidding interval should be based on more than two records.  相似文献   

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