Warm weather transport of broiler chickens in Manitoba. I. Farm management factors associated with death loss in transit to slaughter

This observational study was conducted to identify flock of origin level factors associated with mortality during transport to slaughter of 1 090 733 Manitoba broiler chickens in spring and early summer. The death loss in transit was 0.346% (3778 birds). Death loss on the farm of origin during the growing phase of production and bird body weight at slaughter were associated with increased mortality in-transit. Death loss during production significantly exceeded, while crowding of growing birds was significantly less than, European proposed animal welfare standards.     

青南牧区牧户家畜生产及雪灾防治

采用入户访谈方法,对青南牧区典型雪灾地达日县、玛多县和称多县牧户家畜养殖结构、繁殖成活率、出栏量,冷季死亡、掉膘和补饲情况,牧户暖棚建设和收支及对冬春雪灾设计方案效益系统分析。结果表明,研究区户均家畜养殖数为82.5~423.2AU(羊单位,animal unit),家畜年补饲水平为1.2~26.5CNY·AU-1,牧户家畜几乎不出栏,有暖棚设施的牧户占总牧户的1/3,收入主要靠政府补贴,饲草料储备低,占家庭总开支不到5%。牧户应对雪灾能力弱,在大雪灾和中雪灾年份,研究区家畜繁殖成活率分别为41.5%~75.9%和65.0%~86.4%,冷季死亡率分别为13.2%~24.4%和8.2%~12.8%,掉膘率分别为30%~40%和20%~30%。针对牧户家畜管理存在主要问题,本研究提出了一定出栏量+补饲的对策,以减少家畜冬春雪灾死亡损失,提高牧户应对雪灾能力。     

Pre‐slaughter mortality among turkeys related to their transport

Overall mortality among turkeys transported for slaughter in the Czech Republic from 2009 to 2014 was 0.147%. The lowest mortality (0.023%) was found in turkeys transported for distances up to 50 km; longer distances were associated with increasing death rates, with the highest losses (0.543%) recorded for distances from 201 to 300 km. Differences were also found when comparing transport‐related mortality rates according to the season of the year. The highest mortality (0.228%) was associated with transports carried out in summer, whereas the lowest death rates were found in turkeys transported for slaughter in winter (0.105%) and autumn (0.113%). According to the ambient temperatures in which transports associated with the highest death rates among turkeys were carried out (14 to 21°C), it appears that heat stress can be a major factor in the birds’ mortality. However, low ambient temperatures (i.e. below ?2°C) also appear to increase transport‐related mortality, as shown by our results. In addition to shortening the lengths of transport distances, appropriate consideration of prevailing climatic conditions and the sensitivity of turkeys to high and low temperatures during transport may also lead to a reduction in the number of turkeys dying during transport for slaughter.     

Detection and determinants of Escherichia coil O157:H7 in Alberta feedlot pens immediately prior to slaughter.

Food safety risks due to Escherichia coli O157:H7 may be affected by variability in prevalence in or on live cattle at slaughter. Our objectives were to assess the prevalence and risk factors associated with E. coli O157:H7 in feedlot pens immediately prior to slaughter, and assess relationships among methods of monitoring the E. coli O157:H7 status of pre-harvest pens. We studied 84 pens containing a total of nearly 27,000 head of cattle in commercial feedlots in Alberta during 2003 and 2004. Sampling devices (ROPES) prepared from manila ropes were used to detect high prevalence pens. Forty of 84 pens (48%) were classified ROPES-positive. Within pens, fecal prevalence ranged between 0% to 80% (median = 20%) and the hide prevalence ranged between 0% and 30% (median = 0%). Pens that were ROPES-positive had a higher median prevalence for feces (40%) and for hides (3.8%) than those that were ROPES-negative (13.3% and 0%, respectively). The prevalence of E. coli O157:H7 in pens immediately prior to slaughter was found to be quite high or very low even within feedlots and seasons. Factors such as sampling month, temperature, precipitation, pen floor conditions, and water tank cleanliness were associated with E. coli O157:H7 outcome measures, although associated factors were not completely consistent among years and outcome measures. Fecal and hide prevalence are considered primary pre-harvest indicators of potential carcass contamination, but other methods such as ROPES that are associated with these outcomes may provide logistic advantages to efficiently classify pens of cattle as high or low risk to food safety.     

Acute interstitial pneumonia in feedlot cattle: effects of feeding feather meal or vitamin E.

We evaluated the effects of feeding 1.5% cysteine-rich feather meal or 550 IU of vitamin E for 40 d before slaughter on the rates of death and emergency slaughter due to acute interstitial pneumonia (AIP) in commercial feedlots. Blood and lung tissue were collected at slaughter from 83 animals clinically diagnosed with AIP, 40 asymptomatic penmates, and 40 heifers receiving either feather meal (20) or vitamin E (20); the left lung was subsampled for histologic examination. Blood and lung tissue were analyzed for thiol adducts of 3-methyleneindolenine (3ME) and reduced glutathione. Supplementation with feather meal or vitamin E had no effect on the rates of death and emergency slaughter attributable to AIP and did not influence the levels of 3ME or reduced glutathione in blood or lung tissue. Although supplementation with greater amounts of feather meal or vitamin E may have been necessary to significantly affect factors related to feedlot AIP, increased supplementation would be uneconomical for commercial feedlots, given the relatively low incidence of AIP.     

Effects of undernutrition and refeeding on weights of body parts and chemical components of growing Moroccan lambs.

Forty-four intact, male lambs (20 Timahdit and 24 D'man) were used to assess the effects of 22% (from approximately 25 to approximately 20 kg) and 31% (from approximately 25 to approximately 17 kg) live weight loss and the subsequent refeeding to initial BW on changes in body components. Body composition was determined using a serial slaughter technique at 17, 20, and 25 kg live weight during normal growth, weight loss, and refeeding phases. Reduction in live weight from 25 to 20 kg was associated with greater loss of visceral organs (30%) and internal fat (75%) than carcass loss (19%). Further body weight loss (from 20 to 17 kg) involved carcasses to a greater extent than internal organs. The composition of BW loss consisted of 53% water, 28% fat, and 15% protein. Refeeding was associated with a rapid increase in organ weights and less fat regeneration. Although total internal organs recovered only 90% of their original weight, liver and kidneys regained all their weight. At the same slaughter weight, carcass and noncarcass components of refed lambs were leaner because of lower fat content in these components.     

Epidemiological associations between Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae antibody titers and lung lesions in Prince Edward Island swine herds.

A survey of anteroventral (AV) lung lesions, pleuritis and serology for Mycoplasma hyopneumoniae (MH) and Actinobacillus pleuropneumoniae (AP) was conducted on a minimum of 25 slaughter hogs from each of 18 randomly sampled Prince Edward Island farms (producing over 1,000 market hogs per year). The data were analyzed to evaluate the potential role of these two agents as risk factors for the two conditions, using crude and multivariable techniques, as well as individual and herd data. Anteroventral lung lesions were present in 50.5% of hogs at slaughter, and pleuritis was present in 15.4% of the hogs. Least squares multivariable regression was used to analyze the simultaneous ability of MH, AP and MH/AP interaction to predict the herd prevalence of AV lung lesions. Only MH was associated with AV lung lesions (p = 0.035). In spite of this statistical significance, MH accounted for only 53% of the herd variation in prevalence of lung lesions (R2 = 0.529). As well, some herds maintained very low levels of lung lesions despite moderate (up to 30%) prevalence of MH. Discrepancies between the analytic techniques suggested herd-level factors play an important role in the development of lung lesions. Pleuritis did not appear to be associated with either of the agents studied (p = 0.478).     

Economic effect of pneumonia and pleurisy in lambs in New Zealand

AIM: To estimate the cost of pneumonia and pleurisy in lambs to the sheep industry in New Zealand, in order to provide a reference for future cost-benefit calculations for control programmes to reduce the incidence of pneumonia. METHODS: An estimate of the economic cost of pneumonia and pleurisy in lambs was based on: cohort studies of the association between growth rate and the extent of pneumonic lesions at slaughter (n=14 flocks), the prevalence of moderate to severe (MS) pneumonia (> or =10% lung surface area affected) and pleurisy (n=1,719 flocks), the correlation between the prevalence of MS pneumonia and economic loss at the flock level, and data on annual slaughter statistics and carcass value in New Zealand. A stochastic spreadsheet model was developed and run with 1,000 iterations. Input variables represented by probability distributions were growth rate, average cost of loss according to the prevalence of pneumonia per month, carcass value, prevalence of pleurisy, and carcasses downgraded for pleurisy, and annual national slaughter statistics. The output was a posterior distribution of the annual cost of disease. RESULTS: The cost of pneumonia only included the loss associated with reduced growth rate, while mortality due to pneumonia was assumed to be low and was ignored. The cost of pleurisy included the loss associated with downgraded or condemned carcasses. Thus, the simulated annual average cost of pneumonia was NZ$28.1 (95% CI=NZ$15.0-42.0) million, and that of pleurisy NZ$25.1 (95% CI=NZ$10.2-48.1) million. The combined cost of pneumonia and pleurisy averaged NZ$53.2 (95% CI=NZ$32.4-78.9) million. The parameters with the greatest impact on the combined cost of pneumonia and pleurisy were prevalence of pleurisy between March and May, and cost of reduced growth due to pneumonia for lambs slaughtered in June. CONCLUSIONS: The average cost of pneumonia and pleurisy to the sheep industry in New Zealand due to reduced lamb growth and decreased carcass value is likely to be between NZ$32.4 and $78.9 million. This is a conservative estimate, omitting mortalities, indicating that pneumonia and pleurisy have substantial economic impact on sheep farming in New Zealand. Considering that 23,833,000 lambs were slaughtered in 2003/2004 (average value $65.56/lamb), this cost would equate to NZ$1.36-3.31 per lamb. CLINICAL RELEVANCE: Pneumonia and pleurisy are common diseases in lambs in New Zealand, leading to substantial economic loss to producers.     

A three year herd health and management program on thirty Dutch dairy farms. II. Culling strategy and losses caused by forced replacement of dairy cows

Cows are culled at a relatively low age, which causes considerable economic loss. The annual culling rate in the Netherlands has increased from 18.8 per cent in 1951 to 25-30 per cent of the average number of cows in more recent years. The productive life is now about 3.5 years. On the thirty farms of the program group and thirty-one farms of the control group, the main reasons for culling were reproductive failure followed by mastitis and teat injuries. About 60 per cent of culling was due to health problems, the other 40 per cent to low productive capacity, old age, poor workability etc. The annual culling rate varied per farm per year but also per month. The moment of culling in the current lactation, the slaughter value and the age differed per reason. The calculated loss of forced replacement consists of reduction in both production prior to culling and slaughter value. Additionally, there is an idle production period due to lack of an immediate replacement. The biggest loss is caused by lost future income. There was a considerable difference per farm in the loss caused by culling for health problems. A low culling rate due to health problems was associated with longer longevity and a relatively lower loss. Tangible effects due to changes in the farm culling policy may not be evident for some years. The reduction in loss of culling in the program farms compared with the controls was small because the duration (2 1/2 years) of the herd health and management program was too short.(ABSTRACT TRUNCATED AT 250 WORDS)     

Campylobacter spp. in Irish feedlot cattle: a longitudinal study involving pre-harvest and harvest phases of the food chain

The aim of this study was to investigate faecal shedding and transmission of Campylobacter spp. in cohorts of cattle within a feedlot, to assess subsequent contamination of carcasses with this pathogen and to identify risk factors associated with faecal shedding of Campylobacter spp. A cohort of 133 heifers housed in four adjacent pens was examined over a five and a half month period, from entering the feedlot to slaughter. A parallel investigation of individual rectal faecal samples and pen environmental samples were taken at monthly intervals from November to February. The entire outer and inner surfaces of a carcass side of each animal were swabbed immediately following slaughter. Campylobacter spp. were isolated from 322 (54%) of the 600 rectal faecal samples. Campylobacter jejuni and C. coli accounted for 69 and 29.7% of the isolate recovered, respectively. A total of 159 environmental samples were examined, of these Campylobacter spp. was isolated from 46 samples (29%). Campylobacter jejuni and C. coli accounted for 35 and 59% of these isolates, respectively. Campylobacter spp. was not isolated from any of the dressed carcasses. Logistic regression indicated prevalence of Campylobacter spp. faecal shedding within pens was positively correlated to the pen, the month of sampling and the Campylobacter spp. contamination status of the pen dividing bars and the water trough surface. Campylobacter spp. should be considered as a pathogen shed in the faeces of a substantial proportion of feedlot cattle. However, with good hygienic practice during harvest, a very low level of this pathogen can be achieved on dressed carcasses.     

Effect of slaughter on the spontaneous and evoked activity of the brain

The principal blood vessels in the neck which are severed at slaughter in commercial poultry processing plants are described. Mechanical slaughtering methods often severed the spinal cord without cutting the carotid arteries. The manual method of slaughter cut one carotid artery plus one jugular vein. The effects of 9 different slaughtering methods on spontaneous and evoked electrical activity in the brain were examined in anaesthetised chickens and ducks. Severing the spinal cord without cutting the carotid arteries was found to result in death from asphyxia, and cutting one carotid artery plus one jugular vein was one of the slowest methods of killing the birds. Inducing a cardiac arrest at electrical stunning was the quickest method of inducing death. Spontaneous activity in the brain was lost before visual evoked activity. The times before loss of spontaneous activity varied between 23 and 233 s according to the method of slaughter and loss of evoked activity ranged between 90 and 349 s after slaughter.     

Risk factors for death and unwanted early slaughter in Swiss veal calves kept at a specific animal welfare standard

Calf losses (CL, mortality and unwanted early slaughter) in veal production are of great economic importance and an indicator of welfare. The objective of the present study was to evaluate CL and the causes of death on farms with a specific animal welfare standard (SAW) which exceeds the Swiss statutory regulations. Risk factors for CL were identified based on information about management, housing, feeding, and medication. In total, 74 production cohorts (2783 calves) of 15 farms were investigated. CL was 3.6%, the main causes of death were digestive disorders (52%), followed by respiratory diseases (28%). Factors significantly associated with an increased risk for CL were a higher number of individual daily doses of antibiotics (DDA), insufficient wind deflection in winter, and male gender. For administration of antibiotics to all calves of the cohort, a DDA of 14-21 was associated with a decreased risk for CL compared to a DDA of 7-13 days.     

Prevalence of Salmonella spp in cull (market) dairy cows at slaughter.

OBJECTIVE: To determine the prevalence of Salmonella spp in the cecal-colon contents of cull (market) dairy cows at slaughter because of potential public health ramifications. DESIGN: Survey study. SAMPLE POPULATION: Cecal-colon contents collected from 5,087 cull (market) dairy cows at slaughter at 5 slaughter establishments across the United States. PROCEDURE: During 2 periods of the year, winter (January and February) and summer (July through September), 5 cull (market) cow slaughter establishments in the United States--west (WE), southeast (SEE), central (CE), north central (NCE), and south central (SCE)--establishments were visited, and cecal-colon contents of cull dairy cows were obtained at the time of slaughter. Samples were examined by microbiologic culture at a single laboratory for Salmonella spp. RESULTS: Salmonella spp were detected in 23.1% of cecal-colon content samples from cull dairy cows across the 5 slaughter establishments. The highest site prevalence (54.5%) was detected at the WE during the summer period, whereas the lowest was found at the CE during the summer (4.3%) and at the NCE during the winter (4.5%). Considerable variation in the daily prevalence of Salmonella spp was found, particularly at the WE and the SCE. Salmonella spp were isolated from 93% of cecal-colon contents collected on a summer day at the WE. CONCLUSIONS AND CLINICAL RELEVANCE: Results strongly suggest that there is a high prevalence of Salmonella spp in cull dairy cows at slaughter, which could burden Hazard Analysis Critical Control Point programs implemented in slaughter establishments. Procedures to reduce Salmonella load at the dairy farm and during transport to slaughter could reduce the risk of spread during the slaughter process.     

A region on bovine chromosome 15 influences beef longissimus tenderness in steers.

A genome scan was conducted using 196 microsatellite DNA markers spanning 29 autosomal bovine chromosomes and Warner-Bratzler shear force collected at d 2 and 14 postmortem on steaks from the longissimus muscle of 294 progeny from one Brahman x Hereford bull mated to Bos taurus cows to identify QTL for beef tenderness. One QTL was identified and located 28 cM (95% confidence interval is 17 to 40 cM) from the most centromeric marker on BTA15. The QTL interacted significantly with slaughter group. The difference in shear force of steaks aged 14 d postmortem between progeny with the Brahman paternally inherited allele vs those with Hereford was 1.19 phenotypic standard deviations (explained 26% of phenotypic variance) for one slaughter group and was not significant for three other slaughter groups. Apparently, unknown environmental factors present for three of the four slaughter groups were capable of masking the effect of this QTL. The sensitivity of the QTL effect to environmental factors may complicate utilization of markers for genetic improvement. Future research to elucidate the cause of the QTL x slaughter group interaction may lead to improved strategies for controlling variation in meat tenderness via marker-assisted selection, postmortem processing, or live animal management.     

Tryptamine alkaloid toxicosis in feedlot sheep

Tryptamine alkaloid toxicosis (Phalaris staggers) was diagnosed in feedlot sheep. Clinical signs of toxicosis, which were exacerbated by excitement, included gait abnormalities, muscular tremors, nystagmus, and convulsions. An estimated 8% of the most severely affected lambs had clinical signs of toxicosis. Gross lesions detected in the brain of affected lambs consisted of focal gray-green discoloration in the brain stem and thalamus; these areas had microscopic evidence of intraneuronal pigment accumulation. Brain specimens obtained at slaughter indicated that 60% of the lambs had lesions consistent with tryptamine alkaloid toxicosis. Tryptamine alkaloids were found in low concentrations in the feed. Lambs exposed to these feeds had higher death losses than those that were not exposed to the feeds. Cobalt concentration in the feed was higher than that previously reported to be associated with Phalaris staggers.     

Factors related to the risk of neonatal mortality,birth-weight and serum immunoglobulin concentration in lambs in the UK

Neonatal-lamb mortality represents an economic loss and welfare concern. Two factors often associated with the risk of mortality are birth-weight and serum immunoglobulin concentration. We used data from two studies to investigate risk factors for mortality between 2 and 14 days of age and factors affecting birth-weight and serum immunoglobulin concentration at 48 h of age. Dataset 1 included 1339 lambs born on eight farms during the 1995 spring lambing season; dataset 2 included 3172 lambs on seven farms during the 1991 spring lambing season. To account for some of the potential clustering within the data, multilevel models were used. Most (>75%) of the variation in the risk of mortality was at the lamb level. In dataset 1, factors significantly associated with increased odds of lamb mortality included low birth-weight and low serum immunoglobulin concentration. In dataset 2, significant risk factors for mortality included low birth-weight, ewe body-condition score, being born late in the season (relative to other lambs on the farm) and being born in multiple litters. There was a significant interaction between the effects of litter size and birth-weight. (Serum immunoglobulin concentration was not available for dataset 2.) More than half of the variation in birth-weight was at the ewe level, 27% at the lamb level, and 18% at the farm level (dataset 1). Single birth and being male were associated with increased birth-weight in both datasets. In dataset 2 only, increasing ewe condition score and birth early in the study period were also associated with increased birth-weight. Fifty-six percent of the variation in immunoglobulin concentration was at the lamb level, 36% at the ewe level and only 7% at the farm level. Factors associated with reduced serum immunoglobulin concentration included early or late birth in the lambing season, being born later than 14 days after the first lamb born on the farm, multiple-birth litters and maternal mastitis.     

The role of the vertebral arteries in maintaining spontaneous electrocortical activity after electrical stunning and slaughter in calves

This paper examines the role of the vertebral arteries of calves in determining the time to loss of spontaneous electrocortical activity after slaughter by a throat-cut severing the soft tissues of the neck ventral to the spinal column. Four calves with the vertebral arteries ligated took 43 +/- 1.3 s to lose cortical activity after the throat was cut. Four similar animals with intact vertebral arteries and the rostral end of the common carotid arteries clamped immediately after slaughter, to ensure that vertebral blood passed to the brain, took 51 +/-25 s to lose cortical activity. It was concluded that factors other than blood flow from the vertebral arteries contribute to the prolonged time to loss of electrocortical activity after slaughter that has been observed in some calves.     

Onset of insensibility at slaughter in calves: effects of electroplectic seizure and exsanguination on spontaneous electrocortical activity and indices of cerebral metabolism.

Cerebral venous and femoral arterial blood samples were collected from 21 young calves either during electrical stunning and recovery or electrical stunning and slaughter by carotid severance or slaughter without stunning. The blood samples were analysed for PO2, PCO2, pH, glucose and lactate. The results were compared with simultaneous recordings of spontaneous electrocortical (ECOG) activity. Calves subjected to head-only electrical stunning and slaughter became permanently insensible at the time of the stun. The six calves slaughtered without stunning lost sensibility within 10 seconds. One calf, in which a clot formed in the carotid arteries inhibiting bleeding, maintained some evidence of cortical activity beyond 52 seconds; this was high amplitude low frequency activity and analysis by Fast Fourier Transform showed sensibility was not regained. In the remaining calves the ECOG activity was lost on average within 49 +/- 3.5 (SEM) seconds after slaughter. The cerebral extraction of metabolites increased after carotid severance, indicating inadequacy of cerebral bloodflow after slaughter. No correlations were found between indices of cerebral metabolism and the time of loss of cortical function.     

The relationship between infectious and non-infectious herd factors with pneumonia at slaughter and productive parameters in fattening pigs

This paper explores the relationship between infectious and non-infectious herd factors with the occurrence of pneumonia at slaughter and productive parameters in fattening pigs on 39 fattening herds. A questionnaire was used to obtain environmental and management factors (non-infectious factors). Blood samples and lungs were obtained from 35 pigs in each herd at slaughter. Serological testing was performed for antibodies against three respiratory pathogens (infectious factors): porcine reproductive and respiratory syndrome virus (PRRSV), Mycoplasma hyopneumoniae (Mh) and Aujeszky's disease Virus-gE protein (ADV-gE). Lung lesion classifications were catarrhal-purulent bronchopneumonia (CPBP), pleuropneumonia (PLP) and pleuritis. A mean lesion value (MLV) was calculated for each lesion. ANOVA and logistic regression assessed statistical associations among MLV, average daily gain (ADG) and feed conversion ratio (FCR) (dependent variables) with infectious and non-infectious factors (independent variables). Mh vaccination was associated with a significant decrease in CPBP; high Mh seroprevalences was associated with an increased level of CPBP. FCR was negatively related with high seroprevalences for ADV-gE and Mh. No significant associations were seen for ADG.     

Levels of mortality in hens by end of lay on farm and in transit to slaughter in Great Britain

The average mortality for end of lay hens dead on arrival (DOA) was 0.27 per cent (median 0.15 per cent) in a survey of 13.3 million hens transported during 2009. A statistical model of the data indicated main risk factors for DOA to be slaughter plant, distance travelled and external air temperature, with longer journeys and low external air temperatures increasing the risk. Other highly significant risk factors (P<0.001) related to the condition of the birds on farm, where an increased risk of DOA was positively associated with poor feather cover, lower body weight, cumulative mortality of the flock and poor health (indicated by a high proportion of the load rejected at the plant for traumatic injury and disease state). However, the data indicate that by taking risk factors into consideration it is possible to transport hens up to 960 km with low losses in temperate conditions. Mean levels of on-farm mortality, during the laying period, for a total of 1486 flocks were significantly lower in cages (5.39 per cent) than in barn (8.55 per cent), free-range (9.52 per cent) or organic flocks (8.68 per cent) according to producer records a median of seven days before depopulation, with considerable variation between flocks in all systems.