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1.
The objective of the study was to estimate the losses associated with subclinical mastitis (SCM) in crossbred dairy cows in the Central Highlands of Ethiopia. A split udder investigation was performed with 30 cows to determine production losses associated with SCM. Each quarter of the study cows was examined using the California Mastitis Test (CMT) and quarter milk production was measured over a period of 8 days. Production losses were determined for different CMT scores by comparing production of quarters with CMT score 0 to quarters with CMT scores trace, 1, 2 and 3, respectively. Using data from a recently published study, economic losses were determined for different farm sizes and production subsystems by multiplying the prevalence of the respective CMT scores with the production losses associated with these CMT scores. Mean quarter milk production was 0.82 + 0.40 kg per milking in the split udder trial. Milk production was reduced by 1.2%, 6.3%, and 33% in quarters with CMT scores 1+, 2+, and 3+, respectively. Using data from the published study, a quarter with SCM lost an average of 17.2% of its milk production. Production losses associated with SCM were estimated at 5.6% for the Addis Ababa Milk Shed. Stratified losses were highest (9.3%) in urban dairy farms (UDF) and small-scale farms (6.3%). The estimates of the financial losses ranged from US$29.1 in dairy herds in secondary towns (DHIST) to US$66.6 in UDF. A total loss of US$38 was estimated for each cow per lactation. Reducing mastitis in UDF (highest prevalence) to the level of DHIST (lowest prevalence) could reduce the loss by US$35. As this does not include costs associated with treatment or culling of diseased cows, this figure probably underestimates the possible benefits of control measures.  相似文献   

2.
The prevalence, stages and causes of foetal and calf wastage were determined in Brahman (1/2 B, 3/4 B) and Sahiwal (1/2 Sah, 3/4 Sah) and high grade Sahiwal (HGSah) genotypes over a 12-year period. The mean total loss from pregnancy being first diagnosed to weaning was 13.5% (range 9.4 to 19.0%) and was not influenced by cow age. Across all age groups total losses were significantly lower in 1/2 B (11.8%) and 3/4 B (11.7%) than in 1/2 Sah (16.3%) and 3/4 Sah (19.4%) which were in turn significantly lower than in HG Sah (26.5%). Mean prenatal, perinatal and postnatal losses were 3.5%, 4.4% and 5.6%, respectively. For prenatal losses, 42.4% occurred in early-, 34.8% in mid- and 23.0% in late gestation, the prevalence being influenced only by year effects. Perinatal losses were lowest in 3/4 B (2.9%) and highest in 3/4 Sah (8.3%) with other genotypes intermediate. Postnatal losses were lowest in 1/2 B (4.1%) and 3/4 B (5.0%), intermediate for 1/2 Sah (7.2%) and 3/4 Sah (6.2%) and highest in HG Sah (15.5%). In Brahmans, important causes of perinatal and postnatal losses were from unknown causes, and in Sahiwals from bottle teats, unknown causes and factors influenced by the cow. Bottle teats were mostly in cows older than 2 years with the majority being in Sahiwals. A high proportion (44%) of the postnatal losses occurred by 14 days after birth.  相似文献   

3.
The objective of this study was to estimate the annual losses from Mycobacterium avium subspecies paratuberculosis (MAP) for an average, MAP-seropositive, Canadian dairy herd. A partial-budget simulation model was developed with 4 components of direct production losses (decreased milk production, premature voluntary culling, mortality, and reproductive losses). Input values were obtained primarily from a national seroprevalence survey of 373 Canadian dairy farms in 8 of 10 provinces. The model took into account the variability and uncertainty of the required input values; consequently, it produced probability distributions of the estimated losses. For an average Canadian dairy herd with 12.7% of 61 cows seropositive for MAP, the mean loss was $2992 (95% C.I., $143 to $9741) annually, or $49 per cow per year. Additional culling, decreased milk production, mortality, and reproductive losses accounted for 46%, 9%, 16%, and 29% of the losses, respectively. Canadian dairy producers should use best management practices to reduce these substantial annual losses.  相似文献   

4.
The progress in our understanding of the endogenous protein concept over the past century is reviewed. Nondietary proteins found in the digesta at the terminal ileum of poultry, known as endogenous protein loss, are comprised of digestive secretions, mucus and sloughed gut epithelial cells. The measurement of this loss is of fundamental importance because it is an indicator of gut metabolism and is essential to adjust apparent estimates of ileal amino acid digestibility. The ileal endogenous amino acid losses comprise of two components, namely basal and specific losses. The basal losses are fixed and associated with feed dry matter intake, whereas the specific losses are variable and induced by the presence of dietary components such as fibre and anti-nutrients. Currently there is no methodology available to directly measure the specific endogenous losses and these losses are calculated by determining the basal and total(basal plus specific) losses and, then subtracting the basal losses from total losses.The seminal features, specific applications and shortcomings of available methodologies are briefly outlined as well as the practical challenges faced in using the published endogenous amino acid loss values for true digestibility corrections. The relevance of taurine as a component of endogenous protein flow in poultry is identified for the first time.  相似文献   

5.
Perinatal mortality is affected by a variety of management factors and disease processes that create significant losses for the sheep industry. Annual production losses prior to weaning include roughly 15% to 20% of the lamb crop. The majority of these perinatal losses occur during the prenatal, natal, and early postnatal periods, with the predominant wave of mortality occurring during the first several days following birth. Causes of perinatal mortality may vary between flocks and between geographic areas; however, four dominant categories of lamb loss consistently surface: (1) abortions; (2) hypothermia, starvation, and exposure; (3) pneumonia; and (4) stillbirth and dystocia. They account for roughly 50% to 75% of all documented perinatal losses. Veterinarians and producers need to work together to document the type of losses that occur in a given flock and then design economic prevention programs that address these problems. In most cases, traditional prevention programs will need to be replaced by a comprehensive management scheme addressing nutrition, genetics, housing, marketing, lambing husbandry, and labor.  相似文献   

6.
7.
SUMMARY The extent and causes of sheep losses in the semi-arid Mallee region of north-western Victoria were assessed by interviewing the owners of 79 randomly selected farms running 241 flocks in 1987/88 and 245 flocks in 1988/89. Mean annual losses were higher in ram flocks (21%) than in ewe flocks (7%), in flocks of non-Merino sheep (rams 24%, ewes 11%, weaners 5%) than in Merino (rams 11%, ewes 6%, wethers 4%, weaners 4%) and in ewe flocks 3 or more years old (10%) than in young ewe flocks (3.5%). In flocks where losses exceeded 5%, the causes most often reported by farmers were blowfly strike (especially in Merino sheep and weaners), ewe losses in autumn close to lambing, and heliotrope (Heliotropium europaeum) poisoning. Heliotrope poisoning was considered by the authors to be the main reason for the higher losses in old ewes than in young ewes and in non-Merino sheep than in Merino sheep. Losses of ewes associated with pregnancy and lambing were considered by the authors to be often predisposed by liver damage caused by heliotrope poisoning, and high losses in non-Merino ram flocks were attributed to both heliotrope poisoning and their ability to escape through boundary fences. Reasons for continuing high losses due to enterotoxaemia are discussed. Losses due to gastro-intestinal parasites, footrot and foot abscess were low.  相似文献   

8.
The aim of this study was to estimate the production losses due to cystic echinococcosis (CE) in cattle, sheep and goats in Turkey. For this purpose, official records and previously published data in the literature were used. The weighted mean prevalence rates of the disease were calculated to be 7.4% in cattle, 46.3% in sheep and 10.9% in goats. The financial losses were estimated in US$ at 2008 current prices under expected (mean value), optimistic (mean value lowered by 10%), and pessimistic (mean value increased by 10%) scenarios. The production losses in an infected ruminant were estimated as US$ 139.2 (125.3–153.2, under optimistic–pessimistic scenarios) for cattle, US$ 13.7 (12.3–15.1) for sheep, and US$ 13.9 (12.5–15.3) for goats. The nation-wide annual losses due to CE were estimated as US$ 32.4 million (26.2–39.1) for cattle, US$ 54.1 million (43.8–65.5) for sheep and US$ 2.7 million (2.2–3.3) for goats. The nation-wide production losses due to CE in Turkey in 2008 were calculated as US$ 89.2 million (72.2–107.9). The results of this study may provide information to assist decisions of the policy makers in prioritising the allocation of scarce resources in controlling animal diseases in Turkey. However, alternative disease control-eradication programmes and cost-benefit analyses of them are needed for the future studies of this kind to provide better decision support in this area.  相似文献   

9.
Tropical Animal Health and Production - Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis. It causes significant economic losses associated with losses due to slaughter...  相似文献   

10.
The objective of this study was to estimate the direct economic losses due to the condemnation of the liver and large intestine because of internal diseases (multifocal necrosis in the liver (MNL) and inflammation of the large intestine (ILI)), and the indirect losses because of reductions in carcass performance from MNL, bovine abdominal fat necrosis (BFN) and ILI using data from 5383 Japanese Black cattle. Direct losses were estimated by multiplying the price of the condemned part by the frequency of its occurrence owing to the disease. Similarly, indirect losses were estimated as the product of unit carcass price and reduction in carcass weight (CW) due to the disease. The direct impact on the beef cattle industry from MNL and ILI was estimated at around $1.29 million (US$1 = ¥120) per year. A least‐squares analysis showed that MNL had no influence on any carcass trait, whereas BFN and ILI significantly reduced CW, rib eye area and darkened the beef. ILI also reduced rib thickness. The indirect losses from BFN and ILI were estimated as a maximum of $131.7 and $256.4 per animal and around $6.26 million and $4.03 million for the industry, respectively, mostly because of the reduction in CW.  相似文献   

11.
OBJECTIVE: To quantify total fluid loss in sweat of Thoroughbreds during >3 hours of low-intensity exercise in controlled conditions and to calculate and compare estimated ion losses in sweat, according to 3 methods. ANIMALS: 6 exercise-trained Thoroughbreds. PROCEDURE: Fluid and ion losses in sweat were measured in 6 horses exercising at 40% of the speed that elicited maximum oxygen consumption for 45 km. Horses were given a 15-minute rest period at the end of three 15-km exercise phases. Horses completed 2 exercise trials. Ion losses in sweat were calculated, using measurements of local sweating rate and sweat ion composition (SWT), change in net exchangeable cation content (CAT), and change in extracellular ion content (PLAS) derived from plasma total solids and ion concentrations. RESULTS: Measurement of SWT revealed a mean (+/- SEM) fluid loss in sweat during 45 km of exercise of 27.5 +/- 1.6 L. Total ion loss in sweat was approximately 241 g or 7.8 mol with higher sodium losses in the second and third phases of exercise compared with the first phase. Losses of sodium and potassium calculated by SWT or CAT were not significantly different from each other, whereas losses of these ions as determined by PLAS were significantly lower. CONCLUSIONS AND CLINICAL RELEVANCE: Calculation of ion losses from a mean whole body sweating rate extrapolated from either local sweating rate and sweat ion composition or from change in net exchangeable cation content provide similar results, whereas ion losses determined by changes in extracellular ion content derived from plasma total solids and ion concentration results in underestimation of actual losses.  相似文献   

12.
OBJECTIVE: To describe a significant outbreak of foetal infection and subsequent losses due to bovine pestivirus on a 5200 ha beef breeding and fattening property in central Queensland. DESCRIPTION OF THE HERD: The affected herd consisted of 656 cows, including 269 recently purchased cows, and 221 heifers that were joined in December/January 1995/96. There were approximately 2500 cattle on the property. INVESTIGATION: Following the purchase of 269 cows in October 1995, which were mingled with the existing cow herd, losses were experienced due to foetal infection with bovine pestivirus. These losses were recorded between 1996 and 1999 as: reduced pregnancy rates, losses between pregnancy testing (midpregnancy) and branding (calves averaged 3 months-of-age), losses due to pneumonia and ill-thrift between branding and approximately 12 months-of-age, and losses due to ill-thrift and the chronic wasting form of mucosal disease thereafter. All surviving calves were tested for bovine pestivirus in 1997 at an average of 10 months. Fifty-three calves were identified as persistently infected with bovine pestivirus. A further 110 calf losses could reasonably be attributed to bovine pestivirus infection. Persistently infected cattle were always unthrifty compared to their virus negative counterparts. Only one persistently infected calf was identified, on the basis of severe ill thrift, in the 1997 birth cohort and none in 1998. CONCLUSIONS: This outbreak of foetal infection with bovine pestivirus resulted in significant production losses. These losses were recorded over the three years subsequent to the outbreak. Significant numbers of persistently infected calves were not evident among calves born in the two years after this outbreak.  相似文献   

13.
Measures of ileal digestibility (ID) are used routinely as estimates of amino acid (AA) bio-availability in pig feed ingredients. Values for ID may be expressed as apparent (AID), standardized (SID), or true (TID). Values for AID are calculated by deducting the total ileal outflow of AA (the sum of endogenous losses (IAAend) and non-digested dietary AA) from dietary AA intake. The IAAend may be separated into basal losses, which are not influenced by feed ingredient composition, and specific losses induced by feed ingredient characteristics such as anti-nutritional factors and dietary fiber. If the AID values are corrected for total IAAend, then values for TID are calculated. Lack of additivity of AID values in feed formulation may be overcome by correcting AID values for basal IAAend only, which yields SID values. Until reliable procedures for the routine measurement of specific IAAend become available, it is suggested that SID values are used for feed formulation. It is advisable that basal IAAend are measured in digestibility experiments and that these losses are reported with SID values.  相似文献   

14.
In this review, the terminology that is used to describe the bioavailability and ileal digestibility of AA in pig feed ingredients is defined. Aspects of the methodology to establish bioavailability and ileal digestibility values also are discussed, and recommendations about the use of these values are provided. Two main factors can contribute to differences between bioavailability and ileal digestibility of AA. First, some AA, such as Lys, may be absorbed in chemical complexes that preclude their use for metabolism. Second, fermentation in the upper gut may result in a net loss or gain of AA to the animal. In addition, dietary effects on the efficiency of using bioavailable AA intake for tissue growth or milk production should be considered and may be attributed to endogenous AA losses in the hindgut and the metabolic costs associated with endogenous gut protein synthesis and losses. Ileal digestibility values may be expressed as apparent ileal digestibility (AID), standardized ileal digestibility (SID), or true ileal digestibility (TID). These terms are used to specify how ileal endogenous AA losses are reflected in digestibility values. Ileal endogenous AA losses may be separated into basal losses, which are not influenced by feed ingredient composition, and specific losses, which are induced by feed ingredient characteristics such as levels and types of fiber and antinutritional factors. Values for AID are established when total ileal outflow of AA (i.e., the sum of endogenous losses and nondigested dietary AA) is related to dietary AA intake. A concern with the use of AID values is that these are not additive in mixtures of feed ingredients. This concern may be overcome by correcting AID values for defined basal endogenous losses of AA, which yields SID values. Furthermore, if the AID values are corrected for basal and specific endogenous losses, then values for TID are calculated. However, reliable procedures to routinely measure specific endogenous losses are not yet available. It is recommended that basal ileal endogenous losses of AA should be measured in digestibility experiments using a defined protein-free diet and that these losses are reported with observed AID and SID values. It is suggested that SID values should be used for feed formulation, at least until more information on TID values becomes available.  相似文献   

15.
The development of a metabolizable energy (ME) system for horses is described. Predictive equations for gross energy and digestible energy (DE) are revisited. The relationship between feed protein content and renal energy losses and the relationship between feed fibre content and methane energy losses were analysed in a literature review to develop predictive equations for ME. In horses, renal energy losses are much higher than losses by methane energy. Renal energy losses were correlated more strictly to protein intake than to digestible protein intake. The reason probably is that per gram of digestible crude protein energy losses are higher for roughage than for concentrates presumably because phenolic acids of forage cell walls contribute to higher urinary energy losses. However, digestibility of protein is lower in forages than in concentrates. The net result is a rather constant urinary energy loss of 0.008 MJ/g of crude protein in the feed. Methane losses in horses are smaller than in ruminants, presumably because of reductive acidogenesis in hind gut fermentation. Methane energy losses in equines are closely related to crude fibre intake. The mean methane energy losses amount to 0.002 MJ ME/g of crude fibre which can be used to correct for methane losses. Both corrections can be made for any predictive equation for DE. Metabolizable energy is then calculated as follows: ME MJ/kg = DE MJ/kg – 0.008 MJ/g crude protein – 0.002 MJ/g crude fibre. The equation of Zeyner and Kienzle (2002) to predict DE was adapted as mentioned above to predict ME: ME (MJ/kg dry matter) = ?3.54 + 0.0129 crude protein+0.0420 crude fat?0.0019 crude fibre+0.0185 N‐free extract (crude nutrients in g/kg dry matter).  相似文献   

16.
RNA viruses that affect honeybees have been involved in colony losses reported around the world. The aim of the present work was to evaluate the prevalence and distribution of honeybee viruses during 2006-2007 in Spanish professional apiaries, and their association with colony losses. Four hundred and fifty-six samples from apiaries located in different geographic regions of Spain were analyzed. Thirty-seven percent of the samples had viral presence. Most (80%) had one virus and 20% two different viruses. All the analyzed viruses, Deformed Wing Virus (DWV), Israeli Acute Paralysis Virus (IAPV), Black Queen Cell Virus (BQCV), Sacbrood Virus (SBV) and Kashmir Bee Virus (KBV) were detected, but detection rates were lower than expected. According to these results and considering the high prevalence of other honeybee pathogens in Spain, the role of viruses in colony losses in Spain may be discussed.  相似文献   

17.
An experiment was carried out to determine the effects of feeding level, body weight, and time after surgery on basal ileal endogenous amino acid (AA) and N losses in growing pigs. Three pairs of littermate pigs were surgically prepared with ileo-rectal anastomoses. One pig in each pair was anastomosed at 38 kg BW, and the remaining pigs were anastomosed at 67 kg BW. Each pig received at different periods 50, 70, or 90 g of dry matter per kilogram of BW.75 of a protein-free diet according to a Latin square design involving three pigs starting at 45 kg BW and involving six pigs starting at 77 kg BW. For most AA, the time after surgery x feeding level interaction was significant. The basal endogenous losses (in g/d) increased linearly with feeding level at both BW. At the higher BW, the basal endogenous losses (in g/kg DMI) were constant regardless of feeding level, whereas at the lower BW they responded quadratically. At the low feeding level, the endogenous losses were higher than at the medium or high feeding level. We concluded that the basal endogenous losses are proportional to DMI when the feeding level is higher than 70 g/kg BW.75. The AA profile was not influenced by these three variables, but there was a large animal effect. These results suggest that, in digestibility trials, an assessment of the basal ileal endogenous AA losses must be performed on each pig to correct the apparent ileal AA digestibility data.  相似文献   

18.
In-transit losses and stage of transport when deaths occurred were determined for 4 760 213 market-weight pigs produced in 2001 by 4159 Ontario producers and marketed through 117 transport companies to 33 packers located in Canada (96%) and the United States. Approximately 73% and 21% of producers marketed < 2000 pigs and < 500 pigs, respectively. In-transit loss was 0.017%, with 75% of producers losing ≤ 5 pigs annually. Approximately half of in-transit losses occurred on the truck, with 14% of the other deaths occurring at the assembly yards, 4% on the producers’ trucks, and 24% at the abattoir. Fifteen percent of in-transit deaths, representing 1212 pigs, occurred in pigs that were previously identified as abnormal by the transporter or personnel working at the assembly yard or abattoir. Average losses were higher for producers marketing < 2000 pigs, and in-transit loss ratio (ITLR) was highest among those marketing < 100 pigs. Pigs from small farms traveled greater distances than those from larger operations. In-transit losses increased sharply between 590 and 720 km traveled, and decreased at distances > 980 km. Environmental temperatures reached ≥ 31°C for 4.2% of pigs shipped in June, July, and August, with median and mean temperatures of 20.6°C and 20.3°C, respectively, for these months. Twenty percent of all in-transit losses (1617 pigs) occurred in August.  相似文献   

19.
Especially in older pet birds, an unnecessary overconsumption of protein--presumably occurring in human custody--should be avoided in view of a potential decrease in the excretory organs' (liver, kidney) efficiency. Inevitable nitrogen (N)-losses enable the estimation of protein requirement for maintenance, because these losses have at least to be replaced to maintain N equilibrium. To determine the inevitable N losses in excreta of adult amazons (Amazona spp.), a frugivor-granivorous avian species from South America, adult amazons (n = 8) were fed a synthetic nearly N-free diet (in dry matter; DM: 37.8% starch, 26.6% sugar, 11.0% fat) for 9 days. Throughout the trial, feed and water intake were recorded, the amounts of excreta were measured and analysed for DM and ash content, N (Dumas analysis) and uric acid (enzymatic-photometric analysis) content. Effects of the N-free diet on body weight (BW) and protein-related blood parameters were quantified and compared with data collected during a previous 4-day period in which a commercial seed mixture was offered to the birds. After feeding an almost N-free diet for 9 days, under the conditions of a DM intake (20.1 g DM/bird/day) as in seeds and digestibility of organic matter comparable with those when fed seeds (82% and 76% respectively), it was possible to quantify the inevitable N losses via excrements to be 87.2 mg/bird/day or 172.5 mg/kg BW(0.75)/day. Assuming a utilization coefficient of 0.57 this leads to an estimated protein need of approximately 1.9 g/kg BW(0.75)/day (this value does not consider further N losses via feathers and desquamated cells; with the prerequisite that there is a balanced amino acid pattern).  相似文献   

20.
Three finishing trials were conducted to determine the effects of dietary manipulation and management on N losses from open feedlots. In each experiment, 96 steers were assigned randomly to 12 nutrient balance pens. In Trial 1, calves were fed for 180 d during the winter/spring months; in Trial 2, yearlings were fed for 132 d in the summer. In Trials 1 and 2, N losses from pens were compared directly by adding OM to the pen surface or indirectly by feeding digestible ingredients designed to increase OM excretion. The dietary treatment (BRAN) included 30% corn bran (DM basis) replacing dry-rolled corn. Pens where OM was directly added received sawdust applications (SAWDUST) at a rate to match OM excretion from the BRAN diet. These two treatments were compared with a conventional, 75% dry-rolled corn diet (CON). Because CON and SAWDUST diets were identical, performance for both treatments was similar during Trials 1 and 2. The BRAN diet decreased (P < 0.10) gain efficiency during Trials 1 and 2 by 9.5% relative to CON. Fecal N excretion was greater (P < 0.01) for calves and yearlings when BRAN was fed compared with CON. Adding OM to the pen surface increased (P < 0.01) the amount of N in manure removed from pens and reduced (P < 0.10) N losses in Trial 1. Nitrogen losses were not significantly different among treatments in Trial 2. In Trial 3, calves were fed for 166 d during the winter/spring months. A 2 x 2 factorial design was used to evaluate pen cleaning frequency and diets similar to CON and BRAN. Pens were either cleaned monthly or once at the end of the feeding period. Daily DMI was greater (P = 0.01) and ADG was lower (P < 0.01) when cattle were fed BRAN compared with CON. Responses from all three trials indicate a negative effect of BRAN on gain efficiency. Dietary treatment and cleaning frequency interacted for N balance in the feedlot. Nitrogen losses decreased and manure N increased (P < 0.10) for cattle fed BRAN compared with CON when pens were cleaned monthly. Feeding BRAN did not affect total manure N, but resulted in higher N losses when pens were cleaned only once. For all trials, BRAN increased the amount of N remaining in composted manure. Adding OM to pen surfaces and/or cleaning pens more frequently may decrease N losses from open feedlot pens and from compost, although responses seem influenced by ambient temperature or season.  相似文献   

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