Feeding dairy calves and replacement heifers in South-western Sweden: a survey

Daily feed rations, their nutrient contents and live weight gains were recorded for calves and replacement heifers from birth to calving in 122 Swedish dairy herds. Preweaned calves were fed whole milk (45% of the herds), milk replacer alone or milk replacer combined with whole milk. Calf starters were the most frequently used concentrates for preweaned calves, whereas grain dominated for weaned calves and heifers. Grain was supplemented with protein concentrates until 6 months of age and at calving. Grass/clover hay was the dominant forage for preweaned calves, whereas grass/clover silage alone or in combination with hay was the most common forage for calves and replacement heifers from 6 months of age. Heifers grazed semi-natural grasslands, leys or a combination of semi-natural grasslands and leys in 33, 15 and 52% of the herds, respectively. According to Swedish recommendations, calves in a majority of the herds were fed too low concentrations of crude protein from weaning to 6 months of age and calves were fed too low a metabolizable energy content inadequate for a daily weight gain of 700 g at weaning. Median live weight gain from birth to calving was only 567 g per day. Correct feed ration formulations and strategic grazing management could be means to increase weight gain and hence to decrease rearing costs of calves and replacement heifers in Swedish dairy herds.     

Health of cows,calves and young stock on 26 organic dairy herds in Sweden

The health and housing of the stock on 26 organic dairy herds in four counties in eastern Sweden were studied for one year. The herds ranged in size from 12 to 64 cows, and their milk production from 3772 to 10,334 kg per cow per year. A large-animal practitioner visited the farms three times during the year, and a random sample of a third of the cows in each herd were examined. The calves and young stock and their housing were also studied. The calves were in good condition in all but four herds; their serum immunoglobulins varied from almost none to high levels. The young stock were in good condition and in good housing in 20 herds. No cows with clinical signs of metabolic disorders were found. Body condition scores were adequate or good except in two herds. Acetone was analysed in milk samples from individual cows three to six weeks postpartum, and only sporadic cases with high levels were found. The incidence of diseases treated by a veterinarian was lower in the organic herds than the average for the conventional herds in the local dairy association. The findings at the farm visits supported these data, and it is evident that a good standard of health and welfare can be achieved in organic dairy herds.     

A survey on the prevalence of internal parasites of equines in macedonia and Thessalia-Greece

A 3-year survey was conducted to determine the incidence of endoparasitic infection of equines in several regions of Macedonia and Thessalia, Greece. Three hundred fecal and 252 blood samples were examined. Fecal examination was carried out using. Teleman and Faust techniques while blood was examined according to the modified Knott technique. The Graham test was also performed. The prevalence of infection found was 62.4% for horses, 75.7% for donkeys and 89.2% for mules. Strongyles (large and small) were the most common parasitic species found, with a corresponding prevalence of 42.5% and 45.6% for horses, 73.0% and 37.8% for donkeys, and 89.2% for mules. Other parasites found were: Eimeria leuckarti (2.6% in horses and 8.1% in donkeys), Anoplocephala perfoliata (0.4% in horses), Parascaris equorum (1.7% in horses), Oxyuris equi (4.1% in horses and 8.7% in mules), Strongyloides westeri (2.2% in horses, 5.4% in donkeys and 10.8% in mules), Dictyocaulus arnfieldi (0.9% in horses and 2.7% in donkeys) and Setaria equina (2.2% in horses and 2.7% in donkeys).     

Prevalence of Salmonella spp on conventional and organic dairy farms

OBJECTIVE: To describe the occurrence of fecal shedding, persistence of shedding over time, and serogroup classification of Salmonella spp on a large number of dairy farms of various sizes. DESIGN: Longitudinal study. SAMPLE POPULATION: 22,417 fecal samples from cattle and 4,570 samples from the farm environment on 110 organic and conventional dairy farms in Minnesota, Wisconsin, Michigan, and NewYork. PROCEDURE: 5 visits were made to each farm at 2-month intervals from August 2000 to October 2001. Fecal samples from healthy cows, calves, and other targeted cattle groups and samples from bulk tank milk, milk line filters, water, feed sources, and pen floors were collected at each visit. Bacterial culture was performed at 1 laboratory. RESULTS: Salmonella spp were isolated from 4.8% of fecal samples and 5.9% of environmental samples; 92.7% of farms had at least 1 Salmonella-positive sample. The 75th percentile for median within-herd prevalence of Salmonella spp in cattle for 5 sampling visits to a given farm was 2.0% and for maximum within-herd prevalence of Salmonella spp was 13.6%. Farms with a median within-herd prevalence of Salmonella spp of > or = 2.0% accounted for 76.3% of Salmonella-positive samples. There was no significant difference in the prevalence of Salmonella spp between conventional and organic farms. Seasonal differences in Salmonella shedding were observed. More farms had at least 1 serogroup B isolate than any other serogroup, whereas serogroup E1 was the most common among all Salmonella-positive samples. More than 1 serogroup was isolated on 76.4% of Salmonella-positive farms. CONCLUSIONS AND CLINICAL RELEVANCE: Salmonella spp were isolated from > 90% of dairy farms; however, 25% of farms accounted for > 75% of Salmonella-positive samples. This information is critical for the direction of intervention strategies to decrease the prevalence of Salmonella spp on dairy farms.     

A survey to identify economic opportunities for smallholder dairy farms in Bangladesh

Identified economic opportunities for planning interventions greatly increase farmers’ compliance with an extension programme. We investigated opportunities for interventions to increase dairy farmers’ income in four areas of Bangladesh, including the districts of Mymensingh, Khulna-Satkhira, Sirajgonj-Pabna and Chittagong. The data were collected from 1440 dairy farms at a one-day visit and were summarized as the difference between management targets and each herd’s calculated management indices. The average number of lactating cows, feed cost as a percentage of income from milk, milk sold as percentage of milk produced, lactating cows as a percentage of mature cows, and lactating cows as a percentage of total cattle varied from 1.5 to 3.4, from 52.5% to 92.1%, from 78.7% to 92.6%, from 81.9% to 86.7% and from 34.3% to 37.7%, respectively. The average age at first calving, calf production interval, lactation length, and milk production were 35.0–44.3 months, 14.0–17.6 months, 249–286 days and 3.5–7.2 litres, respectively, depending on the locality. The average cost for producing 100 litres of milk was 18.9–35.1 US dollars. The production cost increased when daily milk production per cow decreased (r² = 0.43–0.55). Management improvements directed towards increasing average milk production per cow per day, increasing lactation length, decreasing age to first calving, and decreasing calf production interval could expect to yield an average income increase up to a range of 676.3–1730.6 US dollars depending on the milk-producing area.     

An epidemiological study of selected calf pathogens on Holstein dairy farms in southwestern Ontario.

Fecal samples from calves on 78 randomly selected Holstein dairy farms in southwestern Ontario were screened for Salmonella, Campylobacter jejuni/coli, enteropathogenic Escherichia coli, rotavirus and coronavirus. Based on the observed prevalence, 22% of farms had calves infected with Salmonella, 13% with Campylobacter jejuni/coli, 41% with enteropathogenic E. coli, 19% with rotavirus and 5% with coronavirus. These estimates can be modified, using a method developed by Mullen and Prost (1983) for the World Health Organization, to account for the nature of the laboratory test used. If the test is assumed to have no false positives (that is, if an organism is detected it must be there), then the observed prevalence estimates seen on this study may greatly underestimate the true prevalence of infected premises. The use of nipple feeders for calves was associated with an increased probability of farms having calves shedding detectable fecal levels of Salmonella, E. coli, or one of the two viruses. The use of group pens was associated with an increased odds of finding C. jejuni. Calves with diarrhea on these farms tended to have increased odds of shedding rotavirus, and E. coli with the K99 antigen. However, at the farm level, none of the organisms was associated with above median levels of morbidity. Farms positive for one or other of the viruses had increased odds of experiencing calf mortality relative to virus-negative farms, and farms positive for C. jejuni/coli had decreased odds of mortality.(ABSTRACT TRUNCATED AT 250 WORDS)     

An economic opportunity survey of small dairy farms in Paraguay

Participatory rural appraisal (PRA) in 15 small farms and an economic opportunity survey (EOS) in 13 were carried out in the Cordillera basin of Paraguay to identify production constraints and the best ways to achieve economic gain. PRA showed farmers’ perception was that nutrition was the main constraint. The EOS showed that over 70% of the milk produced was sold in the neighbourhood. The average number of adult cows (lactating and dry cows) per farm ranged from 15 to 120, of which 62.2% to 80% were lactating cows. Milk production per cow on one day ranged from 8.5 to 18.2 litres and average lactation length was more than 300 days. Average age at first calving varied from 31 to 39 months. The highest economic opportunity was observed for increased milk production. Age at first calving and calf production interval were also found to be important constraints. Ultrasonography survey of the ovaries 20 maiden heifers over six months showed inadequate activity. Partially budgeted interventions were instituted to improve nutrition and management of maiden heifers, in-calf cows and those in early lactation. More forages were grown. PRA and EOS were shown to be useful tools in identifying production constraints.     

Effect of nematode infections on growth performance of calves after stabling on commercial dairy farms

Growth performance of calves was assessed on 32 farms during winter housing. Nematode infection was measured by antibody titres, pepsinogen values, and faecal examinations. Half of each herd was treated with ivermectin after stabling. Treatment significantly increased growth rate by an average of +0.059 kg day-1 (P less than 0.01). The effect of treatment varied among herds from -0.078 to +0.210 kg day-1. Only a few of the infection parameters correlated weakly, but positively, to the effect of treatment on growth performance per herd. Untreated control groups showed very different growth rates among herds, ranging from 0.250 to 0.936 kg day-1. This was strongly correlated to several infection parameters. Groups with the highest values for the infection parameters gained approximately 50 kg less over a 4-month period during winter housing than groups with the lowest values for those infection parameters.     

Effect of nematode infections on growth performance of calves during winter housing on dairy farms

Growth performance of calves was estimated by means of heart girth measurements on 48 farms during winter housing (from December to the end of March). Level of exposure to nematode infection was measured by antibody titres, pepsinogen values, and faecal examinations. Half of each herd was treated with albendazole after housing. All infection parameters measured in March were significantly lower in the treated groups than in the untreated control groups. Treatment increased growth rate by an average of +0.007 cm day-1 (N.S.), i.e. +0.036 kg day-1. Effect of treatment varied from -0.075 to +0.100 cm day-1 among herds. This effect of treatment on the growth performance was significantly correlated positively to pepsinogen value (r = 0.321, P less than 0.05 measured in October; r = 0.265, P less than 0.10 measured in December). Control groups showed very different growth rates among herds, ranging from 0.023 to 0.170 cm day-1, i.e. 0.112-0.874 kg day-1. This variation was strongly related to several infection parameters, particularly those measured in October. The most pronounced correlation was found between the average daily gain of the control groups and the mean herd antibody titre against Ostertagia spp. measured in October (r = -0.413, P less than 0.01). These results were consistent with those of a similar study conducted on commercial dairy farms a year earlier.     

Influence of colostral quality on serum proteins in dairy calves raised in smallholder farms in Thailand

The objective of this study was to analyze the influence of colostral quality on serum proteins in calves. Samples were collected from visited farms in Kasetsart University Veterinary Teaching Hospital at Kamphaeng Saen and Nong Pho Animal Hospital. In total, 35 dairy farms contributed 80 dams and calves’ samples. Colostrum samples from 80 dairy cows and blood samples from their calves were taken to evaluate colostral immunoglobulins (Ig) and immunoglobulin G (IgG), and calf serum protein and IgG. Total colostral Ig, colostral and serum IgG, and serum protein were measured by a colostrometer, single radial immunodiffusion, and refractrometer, respectively. Immunoglobulin G and serum protein concentrations increased in the 1st day after birth, and maximum concentrations were seen in the 2nd day and then decreased in the 7th and 14th days. Average?±?SD total colostral IgG concentrations at calving date and at 1 and 2 days after calving were 93.85?±?33.89, 37.11?±?23.51, and 17.23?±?9.4 mg/mL, respectively. The profile of total Ig and IgG concentrations in colostrum had a similar pattern, with the maximum concentrations obtained in calving date and rapidly decreased thereafter. Low IgG concentrations were seen in the 7th and 14th day after calving. The calves that were fed with high quality colostrum had higher serum protein at 1 day of age, 7.49?±?1.01 g/dL, than calves fed with low quality colostrum, 6.40?±?0.86 g/dL (P?<?0.01). The increase in serum protein after first colostrum feeding of high and low quality colostrum was 1.55?±?1.07 and 0.81?±?0.69 g/dL, respectively (P?=?0.02).     

Paratuberculosis on small ruminant dairy farms in Ontario,Canada: A survey of management practices

A cross-sectional study was undertaken (October 2010 to August 2011) to determine the risk factors for dairy goat herds and dairy sheep flocks testing positive for paratuberculosis (PTB) in Ontario, Canada. A questionnaire was administered to 50 producers during a farm visit in which concurrently, 20 randomly selected, lactating animals over the age of 2 years underwent sampling for paratuberculosis testing. Only 1 of 50 farms (2.0%) was closed to animal movement, whereas 96.6% of dairy goat farms and 94.1% of sheep farms purchased livestock from other producers. Only 10.3% of dairy goat, and no dairy sheep farms used artificial insemination. Manure was spread on grazing pastures by 65.5% and 70.6% of dairy goat and dairy sheep farms, respectively. Because of the high true-prevalence of paratuberculosis infection detected, no risk factor analysis could be performed. This study demonstrates that biosecurity practices conducive to transmission of PTB are highly prevalent in Ontario small ruminant dairy farms.     

Baseline survey of health prophylaxis and management practices on Swiss dairy farms

Health prophylaxis management practices have acquired a major role in the success of dairy herd health programs, however, little is known about the scope and level of implementation on Swiss dairy farms. The main objective of this study was therefore to provide a general overview of the most important preventive measures which are currently being used on these farms. In March 2011, an online survey with 75 questions was sent to 2'285 randomly selected Swiss dairy farmers. Response rate by question ranged from 35 to 53 %. Within this study, answers were compared between dairy farms with a tie-stall (n = 739) and farms with a free-stall (n = 458). Homeopathic treatments were used by 51 % of the dairy farmers and antibiotic dry cow treatments by 94 %. Farmers with a tie-stall tended to carry out more prophylactic treatments against external parasites, vaccinated their cows more frequently against Clostridium chauvoei and Moraxella bovis, and carried out claw trimming more frequently than dairy farmers with a free-stall. A higher proportion of dairy farmers with a free-stall had a written feeding plan, carried out regular feed analysis, wore an apron and rubber gloves during milking, and carried out post milking teat disinfection more frequently than dairy farmers with a tie-stall. The data collected in this survey could assist in improving future dairy health communication campaigns in Switzerland.     

Reversal of xylazine-induced sedation in dairy calves with atipamezole: A field trial

Dairy calves immobilized with xylazine (XYL) were given atipamezole-HCl (ATI) at different XYL:ATI dose ratios (w/w) for reversal and the antagonistic effect of xylazine was evaluated. Control animals received saline for comparison. Intramuscular administration of xylazine (0.139–0.357 mg/kg) induced sedation with complete immobilization in all animals (n=195) and there were no spontaneous recoveries before injection of atipamezole or saline. Atipamezole was given 10–81 min and saline 25 min after xylazine administration. Intramuscular administration of atipamezole at XYL:ATI dose ratios of 5:2 (n=11), 10:3 (n=21), 4:1 (n=21) and 5:1 (n=25) effectively antagonized the xylazine-induced immobilization and sedation. The mean times (standard deviation) from injection of atipamezole until the animals were standing for these dose ratio groups were 6.09 (3.12), 5.15 (2.87), 6.35 (2.54) and 7.86 (3.11) min, respectively. The mean time to standing for control animals (n=11) was 94.1 (3.0) min. Intravenous administration of atipamezole at XYL:ATI dose ratios of 10:3 (n=7), 4:1 (n=33), 5:1 (n=16), 8:1 (n=27) and 10:1 (n=9) rapidly reversed the xylazine-induced immobilization and sedation. The mean times (standard deviation) from injection of atipamezole until the animals were standing for these dose ratio groups were 0.98 (0.22), 1.32 (0.48), 1.09 (0.34), 1.39 (0.52) and 1.60 (0.69) min, respectively. The mean time to standing for control animals (n=14) was 88.1 (13.1) min.Animals given high doses of atipamezole (dose ratio groups 5:2 intramuscularly, 10:3 intravenously and 4:1 intravenously) showed signs of excitement while in animals given low doses of atipamezole (dose ratio groups 5:1 intramuscularly and 10:1 intravenously) resedation and relapse into recumbency occurred. Medium doses of atipamezole (dose ratio groups 10:3 intramuscularly, 4:1 intramuscularly, 5:1 intravenously and 8:1 intravenously) did not cause any undesirable side-effects or resedation, and can be recommended for reversal of xylazine-induced sedation in dairy calvesAbbreviations ATI atipamezole-HCl - BW body weight - IM intramuscular - IV intravenous - SD standard deviation - XYL xylazine