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1.
    
The aim of this paper was to validate an alternative multi-criteria evaluation system to assess animal welfare on farms based on the Welfare Quality® (WQ) project, using an example of welfare assessment of growing pigs. This alternative methodology aimed to be more transparent for stakeholders and more flexible than the methodology proposed by WQ. The WQ assessment protocol for growing pigs was implemented to collect data in different farms in Schleswig-Holstein, Germany. In total, 44 observations were carried out. The aggregation system proposed in the WQ protocol follows a three-step aggregation process. Measures are aggregated into criteria, criteria into principles and principles into an overall assessment. This study focussed on the first two steps of the aggregation. Multi-attribute utility theory (MAUT) was used to produce a value of welfare for each criterion and principle. The utility functions and the aggregation function were constructed in two separated steps. The MACBETH (Measuring Attractiveness by a Categorical-Based Evaluation Technique) method was used for utility function determination and the Choquet integral (CI) was used as an aggregation operator. The WQ decision-makers’ preferences were fitted in order to construct the utility functions and to determine the CI parameters. The validation of the MAUT model was divided into two steps, first, the results of the model were compared with the results of the WQ project at criteria and principle level, and second, a sensitivity analysis of our model was carried out to demonstrate the relative importance of welfare measures in the different steps of the multi-criteria aggregation process. Using the MAUT, similar results were obtained to those obtained when applying the WQ protocol aggregation methods, both at criteria and principle level. Thus, this model could be implemented to produce an overall assessment of animal welfare in the context of the WQ protocol for growing pigs. Furthermore, this methodology could also be used as a framework in order to produce an overall assessment of welfare for other livestock species. Two main findings are obtained from the sensitivity analysis, first, a limited number of measures had a strong influence on improving or worsening the level of welfare at criteria level and second, the MAUT model was not very sensitive to an improvement in or a worsening of single welfare measures at principle level. The use of weighted sums and the conversion of disease measures into ordinal scores should be reconsidered.  相似文献   

2.
    
The aim of this paper was to present an alternative multi-criteria evaluation model to assess animal welfare on farms based on the Welfare Quality® (WQ) project, using an example of welfare assessment of growing pigs. The WQ assessment protocol follows a three-step aggregation process. Measures are aggregated into criteria, criteria into principles and principles into an overall assessment. This study focussed on the first step of the aggregation. Multi-attribute utility theory (MAUT) was used to produce a value of welfare for each criterion. The utility functions and the aggregation function were constructed in two separated steps. The Measuring Attractiveness by a Categorical Based Evaluation Technique (MACBETH) method was used for utility function determination and the Choquet Integral (CI) was used as an aggregation operator. The WQ decision-makers’ preferences were fitted in order to construct the utility functions and to determine the CI parameters. The methods were tested with generated data sets for farms of growing pigs. Using the MAUT, similar results were obtained to the ones obtained applying the WQ protocol aggregation methods. It can be concluded that due to the use of an interactive approach such as MACBETH, this alternative methodology is more transparent and more flexible than the methodology proposed by WQ, which allows the possibility to modify the model according, for instance, to new scientific knowledge.  相似文献   

3.
There is a large demand for holistic welfare assessment systems that result in a singular balanced summary of welfare. The Welfare Quality® (WQ) broiler protocol summarizes 18 welfare measures into four principles (‘good feeding’, ‘good housing’, ‘good health’ and ‘appropriate behaviour’), which are then integrated into one overall category (‘excellent’, ‘enhanced’, ‘acceptable’ or ‘not classified’). But the protocol is time consuming which hampers implementation. Furthermore, WQ’s aim to assess animal welfare in a wide range of husbandry systems may decrease its ability to discriminate between flocks from the same system. We applied the protocol in the context of intensive indoor rearing to assess whether it discriminated sufficiently between flocks, could be shortened without losing essential information, and provided a balanced summary of welfare. The vast majority of the flocks (88%) received the same overall classification (acceptable) whilst all other flocks received an adjacent classification (enhanced), suggesting poor discriminative capacity. For 95% of the flocks overall classification was explained by two measures only (‘drinker space’ and ‘stocking density’). A system based on these two measures would reduce assessment time from 3.5 h to a few minutes. However, both measures’ validity can be questioned as they are risk factors for poor welfare rather than animal-based outcome measures and they suffer from methodological weaknesses. Furthermore, the possibility for such an extreme simplification raises doubts on whether the overall classification reflects a balanced summary of different welfare aspects. In line with this, overall classification was not affected by replacing single measures within the ‘good health’ and ‘appropriate behaviour’ principles with realistically attainable minima or maxima for intensively reared flocks. Even replacing either of these two principles entirely with their realistically obtainable minimum or maximum did not affect classification. Such insensitivity to change may discourage attempts to improve the welfare of intensively reared flocks when assessments are made based on the overall classification. This calls for an adjustment of the classification system, which is currently being developed by the Welfare Quality Network.  相似文献   

4.
Animal welfare has become an important subject of public and political debate, leading to the necessity of an objective evaluation system for on-farm use. As welfare is a multi-dimensional concept, it makes sense to use a multi-criteria aggregation system to obtain an overall welfare score. Such an aggregation system is provided by the Welfare Quality® Network. The present paper focusses on the assessment of the multi-criteria evaluation model included in the Welfare Quality® protocol for growing pigs in order to aggregate the animal-based indicators first to criteria, then to principles and finally to an overall welfare score. Specifically, the importance of the indicators on the overall assessment of growing pig farms is analysed in a given population which consisted of a total of 198 protocol assessments carried out on a sample of 24 farms in Germany. By means of partial least squares modelling, the influence of measures in the calculation procedure is estimated by calculation and interpretation of Variable Importance for Projection (VIP) scores. Variable Importance for Projection scores revealed some meaningful, unexpected influences as the multi-criteria evaluation model of Welfare Quality® aimed at avoiding interferences and double-counting. Some of these influences led to the assumption that some measures might have potential as iceberg indicators, whereas others showed lesser importance. Thus, feasibility can be gained by the deletion and special weighting of indicators according to their importance. Altogether, the study is an essential contribution to the further development of the Welfare Quality® protocols as well as the application of multi-criteria decision systems in the field of animal welfare science in general.  相似文献   

5.
Evaporative cooling for Holstein dairy cows under grazing conditions   总被引：1，自引：0，他引：1  
Twenty-four grazing Holstein cows in mid and late lactation were randomly assigned to two treatment groups: control and cooled. The trial was performed at the Experimental Dairy Unit, Rafaela Agricultural Experimental Station (INTA), Argentina. The objective was to evaluate the effects of sprinkler and fan cooling before milkings on milk production and composition. The effects of the cooling system on rectal temperature and respiration rate were also evaluated. Cooled cows showed higher milk production (1.04 l cow–1 day–1). The concentration and yield of milk fat and protein increased in response to cooling treatment. The cooling system also reduced rectal temperature and respiration rate. No effects were observed on body condition. It was concluded that evaporative cooling, which is efficient for housed animals, is also appropriate to improve yields and animal well-being under grazing systems. These results are impressive since the cooling system was utilized only before milkings, in a system where environmental control is very difficult to achieve. This trial was performed during a mild summer. The results would probably be magnified during hotter weather.  相似文献   

6.
    
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.  相似文献   

7.
    
It is well-established that altering the proportion of starch and fibre in ruminant diets can alter ruminal and post-ruminal digestion, although quantitative evidence that this reduces enteric methane (CH4) production in dairy cattle is lacking. The objective of this study was to examine the effect of varying grass-to-maize silage ratio (70 : 30 and 30 : 70 DM basis), offered ad libitum, with either a concentrate that was high in starch or fibre, on CH4 production, intake, performance and milk composition of dairy cows. A total of 20 cows were allocated to one of the four experimental diets in a two-by-two factorial design run as a Latin square with each period lasting 28 days. Measurements were conducted during the final 7 days of each period. Cows offered the high maize silage ration had a higher dry matter intake (DMI), milk yield, milk energy output and lower CH4 emissions when expressed per kg DMI and per unit of ingested gross energy, but there was no difference in total CH4 production. Several of the milk long-chain fatty acids (FA) were affected by forage treatment with the most notable being an increase in 18:0, 18:1 c9, 18:2 c9 c12 and total mono unsaturated FA, observed in cows offered the higher inclusion of maize silage, and an increase in 18:3 c9 c12 c15 when offered the higher grass silage ration. Varying the composition of the concentrate had no effect on DMI or milk production; however, when the high-starch concentrate was fed, milk protein concentration and milk FAs, 10:0, 14:1, 15:0, 16:1, increased and 18:0 decreased. Interactions were observed for milk fat concentration, being lower in cows offered high-grass silage and high-fibre concentrates compared with the high-starch concentrate, and FA 17:0, which was the highest in milk from cows fed the high-grass silage diet supplemented with the high-starch concentrate. In conclusion, increasing the proportion of maize silage in the diets of dairy cows increased intake and performance, and reduced CH4 production, but only when expressed on a DM or energy intake basis, whereas starch-to-fibre ratio in the concentrate had little effect on performance or CH4 production.  相似文献   

8.
Behavior and performance changes when tied dairy cows were moved to a loose housing system in a cubicle system were investigated. Behavioral observations were made for 3 consecutive days in 3 periods after transition. The cows (n = 105) were observed on 18 sampling occasions for 1 month. Recordings were made of body positions and general and social behaviors. Monthly milk records were collected 1 year before and 1 year after transition. Cows walked more during the 1st observation period than during the other periods (p < .05). Walking activity also differed between days when nested to period (p < .05). During the 1st period, cows ruminated while standing more than during the 3rd period (p < .05). Cows ate and groomed less and vocalized more during the 1st period (p < .05). It was concluded that after transition from a tied to a cubicle system, several behaviors were affected during the 1st days, and milk production of multiparous cows was negatively affected, although this effect was not long-term.  相似文献   

9.
    
The effect of rate of substitution of processed, urea-treated whole-crop wheat (pWCW) for grass silage on intake, performance and whole-tract digestibility was evaluated using 44 dairy cows. Cows received 10.5 kg of concentrates per day and one of the following forage mixtures (dry matter (DM) basis): grass silage alone (W-0); 0.75 grass silage, 0.25 pWCW (W-25); 0.5 grass silage, 0.5 pWCW (W-50) or 0.25 grass silage, 0.75 pWCW (W-75). Forage DM intake increased linearly with inclusion rate of pWCW from 9.7 kg DM per day in cows fed W-0 to 14.6 kg DM per day in W-75. By contrast, milk and protein yield (kg/day) were higher (P < 0.05) in cows receiving W-25 compared with W-0, but there was no effect (P>0.05) of treatment on fat yield (kg/day). From week 11 of the experiment onwards, body condition score increased with rate of inclusion of pWCW (P < 0.05). Whole-tract apparent digestibility of organic matter (OM) and fibre (kg/kg), decreased linearly with rate of inclusion of pWCW. Assuming a constant digestibility of starch in the other diet components, the apparent digestibility of starch in pWCW was 0.95 kg/kg and was not affected by rate of inclusion (P>0.05). Four continuous culture vessels were used to determine the effect of rate of inclusion of pWCW on ruminal metabolism in four periods, each of 14 d duration with sampling conducted on days 9 to 14. Vessel ammonia concentration increased linearly (P < 0.05) with rate of inclusion of pWCW whilst mean pH tended (P = 0.06) to decrease. The ratio of acetate to propionate increased from 2.5 in vessels receiving W-0 to 3.2 in those receiving W-75 (P < 0.001). There was no effect (P>0.05) of treatment on digestibility (g/g) of OM, fibre or starch or microbial protein flow (g/day). It is concluded that forage DM intake increased linearly with rate of inclusion of pWCW, but there was no further improvement in milk yield from inclusion rates above 0.25 of the forage DM, with body condition score increasing instead. Increasing the inclusion rate of pWCW resulted in a more ketogenic volatile fatty acid profile but did not affect the efficiency of microbial protein synthesis when determined in vitro.  相似文献   

10.
    
This review deals with the behaviour of river buffaloes (Bubalus bubalis), in confinement and in extensive conditions, also focusing on the effects of different housing and rearing conditions on their welfare. The behavioural repertoire expressed by buffaloes in extensive and intensive conditions is similar to those displayed by other domestic ruminants. However, through natural selection, buffaloes have also acquired several morphological, physiological and behavioural (i.e. wallowing) adaptations to hot climatic conditions. Buffaloes kept in intensive conditions and having no access to pasture and water for wallowing extend their periods of idling and are less often involved in investigative activities. Confinement is also associated with a reduction of space; however, no specific studies have been carried out to determine the specific requirements of this species. Space restriction can adversely affect various aspects of buffalo welfare, such as health (increased levels of lesions and injuries), social behaviour (increased number of agonistic interactions) and heat dissipation. The buffaloes, originating from tropical areas, are well adapted to large variations in food availability and quality, and to dietetic unbalances. As to human animal relationship, it has been observed that the incidence of stepping and kicking behaviour of buffaloes in the milking parlour is positively correlated with the frequency of oxytocin injections, whereas the frequency of positive stockperson interactions with the animals such as talking quietly, petting and gentle touching are negatively correlated with the number of kicks during milking. Data from farms where both dairy cattle and buffaloes are present show that avoidance distance measured in the pen is lower in buffaloes than in cattle. This may be attributed to the fact that buffaloes are generally recognised to be curious animals. Finally, the effects of different farming practices on animal-related indicators are described. However, these measures should be integrated into a monitoring protocol, such as the Welfare Quality® scheme, to reliably assess buffalo welfare in the current intensive farming conditions.  相似文献   

11.
    
Increased economic, societal and environmental challenges facing agriculture are leading to a greater focus on effective way to combine grazing and automatic milking systems (AMS). One of the fundamental aspects of robotic milking is cows’ traffic to the AMS. Numerous studies have identified feed provided, either as fresh grass or concentrate supplement, as the main incentive for cows to return to the robot. The aim of this study was to determine the effect of concentrate allocation on voluntary cow traffic from pasture to the robot during the grazing period, to highlight the interactions between grazed pasture and concentrate allocation in terms of substitution rate and the subsequent effect on average milk yield and composition. Thus, 29 grazing cows, milked by a mobile robot, were monitored for the grazing period (4 months). They were assigned to two groups: a low concentrate (LC) group (15 cows) and a high concentrate (HC) group (14 cows) receiving 2 and 4 kg concentrate/cow per day, respectively; two allocations per day of fresh pasture were provided at 0700 and 1600 h. The cows had to go through the AMS to receive the fresh pasture allocation. The effect of concentrate level on robot visitation was calculated by summing milkings, refusals and failed milkings/cow per day. The impact on average daily milk yield and composition was also determined. The interaction between lactation number and month was used as an indicator of pasture availability. Concentrate allocation increased significantly robot visitations in HC (3.60±0.07 visitations/cow per day in HC and 3.10±0.07 visitations/cow per day in LC; P<0.001) while milkings/cow per day were similar in both groups (LC: 2.37±0.02/day and HC: 2.39±0.02/day; Ns). The average daily milk yield over the grazing period was enhanced in HC (22.39±0.22 kg/cow per day in HC and 21.33±0.22 kg/cow per day in LC; P<0.001). However the gain in milk due to higher concentrate supply was limited with regards to the amount of provided concentrates. Milking frequency in HC primiparous compared with LC was increased. In the context of this study, considering high concentrate levels as an incentive for robot visitation might be questioned, as it had no impact on milking frequency and limited impact on average milk yield and composition. By contrast, increased concentrate supply could be targeted specifically to primiparous cows.  相似文献   

12.
    
Two experiments were conducted to examine the effects of depriving dairy cows of the ability to feed and lie down for short periods, on behaviour and production. In experiment 1, cows were deprived by confining them in pairs in a pen for 2 or 4 h, and they more frequently exhibited behaviour likely to suggest discomfort - leg stamping, repositioning themselves, shifting their weight between legs and butting. After deprivation, the cows deprived for 2 h made up their lost feeding time within 24 h, but cows deprived for 4 h did not restore their feeding time within the 41-h period of observation. Lying time was not restored in either treatment within the 41-h period. Milk yield was not affected by the treatment. However, in experiment 2, when cows were deprived of feeding and lying for 4 h, during which time their hooves were trimmed (which is likely to be a painful and stressful procedure and result in some discomfort for a period post-trimming) the evidence suggested that milk yield was reduced by approximately 2 l/day for 3 days, with corresponding increases during the subsequent 2 days. Walking speed on returning to the herd was the same as before the treatment. In summary, temporary deprivation of feeding and lying for 2 and 4 h/day induced behaviours that were indicative of discomfort and frustration but had no negative effect on milk production, except when 4 h of deprivation was accompanied by foot trimming.  相似文献   

13.
Emulsifiable concentrate and microencapsulated formulations of permethrin were evaluated for residual activity against stable flies on lactating dairy cows. Cows were treated in the field with each formulation and hair was clipped from the leg and shoulder area, and bioassayed at 1, 2, 3, 4, 7 and 14 days after treatment. Significantly more stable flies died when exposed to hair sampled 3, 4 and 7 days after treatment from the shoulder than from the lower leg. Analysis with gas chromatography of hair samples showed no detectable permethrin residues on shoulder or leg hair 72 h after treatment with the emulsifiable concentrate formulation. Microencapsulated permethrin was still detectable on hair sampled from both locations 7 days after treatment. The permethrin concentration on the leg hair was approximately 50% of the shoulder hair concentration after 3 days, with the leg hair residue dropping to 31% of shoulder level after 7 days.  相似文献   

14.
嗜中性粒细胞是防止病原入侵的第一道防线,且已有研究表明嗜中性粒细胞在奶牛乳腺免疫中发挥着关键作用。文章运用双向凝胶电泳方法对临床型乳房炎奶牛与健康奶牛嗜中性粒细胞差异表达蛋白质组进行分析,成功获得分辨率较高、重复性较好的奶牛嗜中性粒细胞双向电泳凝胶图谱,并通过MALDI-TOF MS鉴定获得差异表达的蛋白质7种,主要涉及细胞代谢、氧化应激、炎症反应等相关蛋白通路。实验获得的临床型乳房炎奶牛与健康奶牛嗜中性粒细胞差异表达蛋白有望为今后奶牛乳房炎的抗病育种研究提供理论依据。  相似文献   

15.
    
Milk production data from Holstein × Zebu cows in small farms (2.4 cows per farm on average) in Maharashtra, India, followed by Bharatiya Agro Industries Foundation (BAIF), an Indian non-governmental organisation, were analysed to evaluate the impact of simplified milk-recording systems. The aim was to investigate, in developing tropical areas, less-costly protocols compared with the one currently implemented at BAIF, used as a reference. The latter can be considered an 'AT2' protocol with the recording made by specialised technicians at 2-week intervals. The simplified protocols were simulated from an initial data file by sampling test days according to each protocol. Bias and accuracy on the 305-day cow milk production and on the resulting reliability of the estimated breeding value of bulls were the criteria used in the comparison with the reference protocol. One type of simplified protocol considered an increase in the interval between two tests to at least 4 and up to 8 weeks. Another alternative studied corresponded to the situation where milk yield information measured by the farmer is collected by the artificial insemination technicians themselves when visiting a farm. This could be an option in the case of very small herd sizes (two or three cows). The results suggest that simplifying the current milk-recording protocol leads to a clear decrease in accuracy of estimating 305-day cow production but it has a limited effect on the reliability of bull proofs. No economic comparison was carried out, but the results strongly suggest that properly managed simplified milk-recording schemes could permit a substantial decrease of costs of milk recording per cow without damaging the efficiency of progeny testing in tropical areas with small herd size. Moreover, with the proposed simplified milk-recording protocols, up to three to four times more bulls could be tested with the same number of records.  相似文献   

16.
    
Data were collected on reproductive, health and production events in 45 dairy herds in southwestern and eastern Ontario, Canada, from July 1990 to July 1993. Mean and median days in milk at first estrus, at first service, and at conception were 85.1 and 83.9, 94.0 and 88.9, and 126.3 and 115.5 d, respectively. The mean estrus detection rate was 48.3%, with a minimum of 28.4% and a maximum of 64.2%. The mean overall conception rate was 46.7%, with a minimum of 29.8% and a maximum of 70.7%. The most commonly used used therapeutic agents were GnRH (11.5% lactational incidence risk) and PG (13.1% lactational incidence risk). Estrus management accounted for the largest portion of PG use in the herds studied (69.4%). Results of a two sample t-test indicated no significant difference in reproductive performance among herds housed in free-stall compared with those housed in tie-stall barns. Multivariate linear regression models of 3 reproductive performance measures indicated that cows with ovarian cysts and/or increased peak milk production had significantly longer calving-to-first estrus and calving-to-conception intervals as well as lower conception rates than average producing cows without cysts. Cows with metritis were found to have significantly shorter calving-to-conception intervals but no detectable difference in conception rate or calving-to-first estrus interval than their herdmates. As lactation number increased reproductive performance improved. Cows that were observed in estrus earlier conceived earlier. Animals receiving uterine infusions had significantly longer calving-to-conception intervals and lower conception rates than their herdmates. There was no detectable difference in reproductive performance for cows treated with GnRH or PG compared with the nontreated cows. An increased estrus detection rate was associated with shorter calving-to-conception intervals and lower conception rates. Based on the range of performance in the study herds, the factors with the greatest potential influence on calving-to-conception interval in the average herd were the estrus detection rate and conception rate.  相似文献   

17.
Relationships between genetic merit for milk production and animal parameters and various parameters of reproductive performance were examined using multilevel binary response analysis in a study of 19 dairy herds for three successive years, representing approximately 2500 cows per year. The proportion of cows intended for rebreeding that were back in-calf again within 100 days of calving (ICR-100) and the proportion of cows that reappeared again with 365 (RR-365) and 400 days (RR-400) of a previous calving were considered in addition to the traditional measures of reproductive performance. Each 100-kg increase in genetic merit for milk yield was associated with an increased interval to first service (IFS) and calving index (CI) of 1.4 ( P < 0.001) and 1.8 days ( P < 0.001), respectively, a 0.5% increase ( P < 0.05) in calving rate to first insemination (CR-1) and 0.8% increase in RR-400. Each £10 increase in £PIN (the economically weighted yield selection index used in the UK that takes account of butterfat and protein yields) was associated with an increased IFS and CI of 1.5 ( P < 0.001) and 3.0 days ( P < 0.001), respectively. Cows with increased genetic merit for milk yield and £PIN were more likely to re-calve (RR-overall; P < 0.001). Each 1000-kg increase in 305-day milk yield was associated with an increased IFS and CI of 3.2 ( P < 0.001) and 7.8 days ( P < 0.001), respectively, and a 13.6 ( P < 0.001), 22.4 ( P < 0.001), 19.9 ( P < 0.001) and 19.0% ( P < 0.001) decrease in CR-1, ICR-100, RR-365 and RR-400, respectively. A 10-kg increase in maximum yield was associated with a 6.6-day increase in CI ( P < 0.001) and a 14.9 ( P < 0.001), 18.3 ( P < 0.001), 9.6 ( P < 0.05) and 14.2% ( P < 0.001) decrease in CR-1, ICR-100, RR-365 and RR-400, respectively. Fertility performance was also associated with season of calving, lactation number and dystocia score. Level of production had a larger effect on fertility performance than genetic merit for milk production suggesting that infertility at an individual cow level is more likely to be associated with increased production and an inability to meet the nutritional requirements of the cow.  相似文献   

18.
    
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19.
    
This pilot study considers space use and behavior patterns for nine chimpanzee mother-offspring pairs. Observations were conducted using instantaneous scan sampling, four times daily, five days a week, for four weeks. Mother-offspring use of vertical space and horizontal space and mother-offspring proximity were observed and analyzed using a Chi Square test. Results suggest mother-offspring pairs use levels above the enclosure floor, spending a majority of time in areas near horizontal bench substrates placed 1.2–2.5 m above the floor. Findings provide information that will assist managers in providing appropriate housing for chimpanzee (Pan troglodytes) mothers and their offspring. © 1994 Wiley-Liss, Inc.  相似文献   

20.
    
Bovine placental lactogen (bPL) is structurally related to prolactin (PRL) and growth hormone (GH). In synergism with steroid and thyroid hormones, bPL is crucial in stimulating the development of the mammary gland, mammary cell differentiation and function. To further explore whether bPL gene is associated with milk production traits, we herein analyzed single-nucleotide polymorphisms (SNPs) within eight regions of bPL gene, which are potentially associated with five milk production traits on 1028 Chinese Holstein cows. Among these, two SNPs, NT7409(T-C) and Nt11246(G-A), were identified. The former is within exon 2; it induces an alteration of amino acid from Val to Ala. The later is within exon 4. It is a synonymous mutation. We found that there were significant associations between NT7409(T-C) and milk and protein yield. Cows of the AA genotype yielded less milk (P = 0.001) and less protein (P = 0.003) than those of genotypes AB and BB. However, on the NT11246(G-A) locus, no significant association was observed in the five milk production traits studied. In addition, bPL has been localized near markers RM185 and CC549051 with a distance of 23.2 cR on BTA 23. It is at the same position as the region including quantitative trait loci (QTLs) affecting milk and protein yields by previous linkage analysis. In summary, our findings demonstrated that the SNP within exon 2 of bPL (NT7409(T-C)) is associated with two milk production traits, and this provided further evidence that bPL could be a major gene-controlling milk production trait in Holstein dairy cattle.  相似文献   

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