[Reflection on the KKM (milk quality) and PBB (periodic visitations): are there perspectives?].
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Animal Welfare↗
Biomedical subjects
J P Noordhuizen
Publications and source records attributed to J P Noordhuizen.
Epidemiology of Cryptosporidium spp. and Giardia duodenalis on a dairy farm.
Prevalences of Cryptosporidium spp. and Giardia duodenalis in relation to age and season were investigated on a dairy farm in The Netherlands over the course of 1year. The whole herd was sampled five times, whereas calves younger than about 2 months were sampled every 2-3 weeks. Associations between diarrhoea and presence of one or more pathogens (Cryptosporidium spp., G. duodenalis, rotavirus) were investigated. Potential transmission routes of Cryptosporidium spp. were evaluated and positive samples of Cryptosporidium spp. and G. duodenalis were identified to genotype level by PCR microsatellite identification and fingerprinting. Shedding of Cryptosporidium spp. was found in all age categories but peaked in calves 1-3 weeks old (39.1%). Herd prevalence of shedding for Cryptosporidium spp. varied from 2.4% in June to 22.2% in December. Shedding of G. duodenalis was found in all age categories but peaked in animals 4-5 months old (54.5%). Herd prevalence of shedding for G. duodenalis varied from 0.8% in June to 15.5% in February. Cryptosporidium spp. and rotavirus appeared to be significantly associated with diarrhoea in calves. Microsatellite analysis showed two different subtypes (C3 and C1) of Cryptosporidium parvum calf strains. Two genotypes of G. duodenalis were found, one positive by A lineage specific PCR and thus closely related to human genotypes and one genotype, which was negative by A and B lineage specific PCR. The results indicate that cow-to-calf and indirect calf-to-calf transmission both are important routes for acquiring infection with Cryptosporidium spp.
Age Factors↗
[From veterinary companionship to veterinary consultation about dairy farms (by way of changing strategies in cattle practice)].
Dairy herd health and production management programmes are used by veterinary practices as a daily routine. However, the potential of this increasingly important source of income is probably not realized completely. The activities of dairy herd health and production management programmes were assessed by both veterinarians and dairy farmers. Subsequently, plans were developed to make herd health and production management programmes beneficial to both parties. For this purpose it is necessary to change the former dairy herd health and production management programme into a more professionally oriented veterinary consultancy. This article describes how this change can be made. Defining the consultancy programme and working in a structured way are essential to gain profit from veterinary consultancy.
Animals↗
[Veterinary herd health consultancy on dairy farms: guidelines for starters].
This paper presents a guideline which can be used when setting up a professional veterinary herd health and production management advisory programme for dairy farms. Earlier research showed that dairy farmers prefer a structured professional programme and ask their veterinary surgeons to provide an optimal veterinary advisory programme for their dairy farms with a clear structure and contents, and well-planned activities. The guideline presented here should aid in providing the farmers with that clarity, structure, and planning. This should ultimately lead to a more professional implementation of veterinary advisory programmes.
Animals↗
WIN EPISCOPE 2.0: improved epidemiological software for veterinary medicine.
Recent changes in veterinary medicine have required quantitative epidemiological techniques for designing field surveys, identifying risk factors for multifactorial diseases, and assessing diagnostic tests. Several relevant techniques are brought together in the package of veterinary epidemiological computer software, WIN EPISCOPE 2.0, described in this paper. It is based on Microsoft Windows and includes modules for the design and analysis of field surveys, control campaigns and observational studies, and a simple mathematical model. It provides comprehensive 'Help' screens and should therefore be useful not only in field investigations but also for teaching veterinary epidemiology.
Animal Diseases↗
[Recognition of cattle veterinarians: what should we do with it??].
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Animals↗
[Chronic wasting: what can we learn from it?].
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Animal Husbandry↗
Variability of acetone in milk in a large low-production dairy herd: a longitudinal case study.
The objective of this study was to relate acetone in milk with cow and management factors in one low producing dairy herd (5260 kg milk per 305-day lactation). Milk acetone was measured in regular monthly milk samples one to three times within 100 days of lactation in 4433 lactations (2639 cows, 7800 measurements) from one herd over a period of 32 months (1988-91). Associations between milk acetone and cow factors and surrogate measures of management were evaluated by variance components of multiple fixed effect models. Lactation stage, calendar month of study, production groups and milk yield were strong, and percentage milk fat and parity were weak predictors of milk acetone. There was a trend of increasing body weight loss from the first to the second month of lactation with increasing milk acetone level. A substantial increase in milk production in 1991 was accompanied by an almost twofold rise in milk acetone. It was concluded that environmental parameters had strong relationships with milk acetone even in this low-producing herd.
Acetone↗
Developments in veterinary herd health programmes on dairy farms: a review.
This review article addresses some major developments in herd health programmes for dairy farms over the last decades. It focuses particularly on herd health and production management programmes that use protocols and monitoring activities. The article further emphasizes the need for merging herd health programmes with quantitative epidemiological principles and methods. Subsequently, this article points to the latest developments regarding quality assurance in the dairy sector and some quality management methods. Quality should be regarded in its broadest sense. The importance of integrating veterinary herd health programmes and quality (risk) management support at a dairy farm level is stressed. Examples are provided.
Animal Husbandry↗
The effect of litter size before weaning on subsequent body development, feed intake, and reproductive performance of young rabbit does.
An experiment was performed to study the effect of litter size before weaning on subsequent body development and composition, feed intake, and reproductive performance of young rabbit does with the objective to improve reproductive performance. Litter size (LS) before weaning (treatment) was 6, 9, or 12 kits. After weaning (30 d), 58 female kits per treatment (in two successive replicates) were reared and fed for ad libitum intake to 14.5 wk of age (end of rearing). At 14.5 wk of age, receptive does were inseminated. Nonreceptive and nonpregnant does were inseminated at 17.5 wk of age. The experiment ended when the second litter was weaned. Part of the animals was slaughtered to determine body composition at the end of the experiment (replicate one) and at the end of rearing (replicate two). At weaning, BW differed among treatments (P < 0.05; 855, 773, and 664 +/- 15 g for LS6, 9, and 12, respectively). Compensatory growth was observed. At the end of rearing, LS12 does were smaller (P < 0.05) than LS9 and LS6 does (3,524, 3,778, and 3,850 +/- 48 g, respectively). After first lactation, no difference in BW among treatments was found. Compared with LS6, empty body weight (BW minus gut, bladder, and uterus content) of LS12 contained more (P < 0.05) nitrogen (32.5 vs 31.1 +/- 0.3 g/kg), more (P < 0.05) ash (30.7 vs 28.3 +/- 0.6 g/kg), and less (P < 0.05) fat (168.6 vs 200.2 +/- 8.6 g/kg). No differences in body composition among treatments were found at the end of the experiment. During rearing, LS12 had the lowest (P < 0.05) daily feed intake (152, 164, and 169 +/- 2 g/d for LS12, 9, and 6, respectively). During the reproductive period, no differences in feed intake among treatments were found. Kindling rate (the number of kindlings per number of inseminations) was not influenced by treatment. In the first parity, total litter size (number of alive and stillborn kits) was lower (P < 0.10) for LS12 than for LS9 (6.4 vs 8.6 +/- 0.5, respectively). When first mating was delayed by 3 wk, an increased (P < 0.05) total litter size was found regardless of treatment (7.5 and 9.4 +/- 0.3 for 14.5, and 17.5 wk, respectively). Decreasing litter size before weaning from nine to six kits did not alter future reproductive performance. Based on results of this study, it seems advisable to perform a limited standardization level (at nine kits) after kindling and postpone first mating to an older age (17.5 wk) to improve reproductive performance.
Animal Husbandry↗
Determination of acetone in cow milk by Fourier transform infrared spectroscopy for the detection of subclinical ketosis.
Fourier transform infrared analysis (FTIR) was used in combination with partial least squares regression (PLS) to predict the concentration of acetone in milk. FTIR spectra were compared with results of a gas-chromatographic head space method. Principal component analysis of whole spectra (3000 to 1000 cm(-1)) suggested to reduce the spectrum of analysis for acetone to 1450 to 1200 cm(-1). A second derivative was applied to the spectra to remove baseline effects and further enhance the spectral features. Full cross-validation was used to compare the reference with predicted acetone concentrations of samples not included in model development. PLS applied to the full spectral range resulted in a complex 19-factor model with a cross-validation error of 0.22 mM. After reducing the spectrum and taking the second derivative, we obtained a model with seven factors that yielded a cross-validation error of 0.21 mM. This compares favorably with a previously reported model with 20 factors and an error of 0.25 mM. Using PLS predictions to identify cows with subclinical ketosis resulted in 95 to 100% sensitivity and 96 to 100% specificity when the threshold for subclinical ketosis was 0.4 to 1.0 mM. The corresponding positive predictive values were > or = 76% and the negative predictive values > 98% throughout an assumed range of subclinical ketosis prevalence of 10 to 30%.
Acetone↗
Effect of monensin on blood ketone bodies, incidence and recurrence of disease and fertility in dairy cows.
Twelve trials designed to test the effect of monensin on milk production were carried out at eight different research farms. Data from these studies were evaluated for effects of monensin on health and reproduction. Monensin was added to the concentrate starting either 2 wk before (293 cows) or 5 wk after calving (601 cows) for periods ranging 16 to 37 wk. Applied after calving, the incidence of clinical mastitis was reduced in the monensin-treated animals. Monensin decreased the rate of intramammary infection (approximated by a change from below to above 250,000 somatic cells in milk) in first lactation heifers by 13%. Indicated by an adjusted incidence rate ratio of 0.58 (P = 0.03), the case incidence of noninfectious lameness decreased from 31% in control cows to 18% in cows receiving monensin before calving. The time from calving to first service was shorter for cows fed monensin before calving. Monensin reduced calving to conception intervals in cows with endometritis during the pretreatment period. No significant effects of monensin were observed for the duration of intra mammory infection (somatic cells in milk above 250,000), infectious lameness, endometritis, cystic ovarian disease, a summary category of 'other diseases,' times from calving to first observed estrus, and from first service to conception.
Animals↗
Relationship between teat-end callosity and occurrence of clinical mastitis.
A longitudinal study in 15 herds, with a total of 2157 cows, was conducted to examine the relationship between teat-end callosity (TEC) and the incidence of clinical mastitis. During the 1.5-yr study period, clinical mastitis was diagnosed by the farmers based on clinical signs. Teat-end callosity was scored every month according to a teat-end callosity classification system, which discriminates between teat-end callosity thickness (TECT) and roughness (TECR). Differences in TECT between healthy and clinical mastitis quarters within infected cows were small but significant 3 mo before (0.13 higher), in the month during which the clinical mastitis occurred (0.08 higher), and in the following 2 mo (0.06 and 0.05 higher). To compare TECT and TECR between cows with and without clinical mastitis, 199 cows with clinical mastitis were paired with control cows based on herd, days in milk, and parity. Clinical mastitis cows had more TEC than their healthy herd mates, particularly when clinical mastitis occurred between the second and fifth months of lactation. Clinical Escherichia coli mastitis in the second or third month of lactation occurred in cows with less TEC than in cows with clinical mastitis caused by other pathogens. Clinical culture-negative, yeast, Klebsiella pneumoniae, and Enterobacter aerogenes mastitis cows had more TECT and TECR than other cows with clinical mastitis in the same month of lactation. Pointed teat ends had higher TECT and TECR than flat or inverted teat ends. Teat-end callosity thickness increased with a higher milk yield at peak production.
Animals↗
Effect of superovulation induction on embryonic development on day 5 and subsequent development and survival after nonsurgical embryo transfer in pigs.
To evaluate the effects of eCG dosage on recovery and quality of Day 5 embryos and on subsequent development and survival after embryo transfer, batches of 5 to 10 donor sows were treated with 1000 or 1500 IU eCG. Recipients from the same batch were synchronously treated with 800 IU eCG. Ovulation was induced with 750 IU hCG (72 h after eCG) in donors and recipients. Donors were inseminated and embryos were collected at 162 h after hCG (120 h after ovulation). Ovulation rate was lower using 1000 IU eCG (28.5+/-11.7; n=48) than 1500 IU eCG (45.7+/-20.3; n=32; P<0.0001). Embryo recovery rate (82.9+/-16.9%) and percentage expanded blastocysts (56.2+/-31.4%) were similar (P>0.05). Expanded blastocysts from each group of sows were pooled into 2 groups within eCG treatment, containing embryos from normally ovulating sows (< or = 25 corpora lutea [CL]) or from superovulated sows (> 25 CL). Average diameter and number of cells of a random sample of the expanded blastocysts per pool were recorded. The average diameter of blastocysts (160.5+/-11.5 microm) was not affected by eCG dosage or ovulation rate (P>0.10). The average number of cells per embryo was higher in the 1000 IU eCG group (84.3+/-15.3) than in the 1500 IU eCG group (70.2+/-1.9; P<0.05) but was similar for normal and superovulated donors within each eCG group (P>0.10). Of the 4 groups, litters of 28 to 30 blastocysts were nonsurgically transferred to 27 synchronous recipients. Pregnant recipients were slaughtered on Day 37 after hCG treatment to evaluate embryonic development and survival. Pregnancy rate for the 1000 and 1500 IU eCG donor groups was 71% (10/14) and 46% (6/13; P>0.10), respectively. The number of implantations and fetuses for the 1000 IU eCG groups was 12.9+/-3.0 and 11.1+/-2.7, and 14.2+/-7.0 and 10.5+/-4.6, respectively, for the 1500 IU eCG groups (P>0.10). After post-priory categorizing the litters of blastocysts to below or above the average diameter (158 microm) of the transferred embryos, irrespective of eCG dosage or ovulation rate, the pregnancy rate was 43% (6/14) and 77% (10/13; P<0.10), respectively. Post-priory categorizing the transferred litters to below or above the average number of cells per embryo litter, irrespective of eCG dosage or ovulation rate, showed no differences in pregnancy rates or number of implantations and fetuses (P>0.10). It was concluded that eCG dosage affects embryonic development at Day 7 after hCG, and this effect was not due to ovulation rate. Embryonic survival after nonsurgical transfer was not related to eCG dosage but tended to be related to the diameter of the blastocysts.
Animals↗
Interaction between ambient temperature and supplementation of synthetic amino acids on performance and carcass parameters in commercial male turkeys.
An experiment with male turkeys was conducted to test the hypothesis that turkey production performance responds positively to extra crystalline amino acid supplementation (lysine, methionine, and threonine) when subjected to a high ambient temperature regimen (HT) in the grower period. Two diets were formulated to provide lysine, methionine, and threonine concentrations that either 1) met the breeder recommendations or 2) contained 10% higher lysine and methionine concentrations from 22 to 134 d of age and 10% higher threonine concentration from 22 to 68 d of age. Both diets were fed at two temperatures (15 or 25 C) from 42 d of age onward. At 134 d of age, turkeys on the HT had generally lower BW than those on the low temperature regimen (LT). Up to 68 d of age and from 106 to 134 d of age, feed intake of turkeys on the HT was significantly lower than that of turkeys on the LT. Up to 42 d of age, feed conversion ratio (FCR) of turkeys on the HT were significantly lower than those of turkeys on the LT. Significant treatment interactions were observed from 22 to 41 d of age. Turkeys fed the amino acid-supplemented diets on the LT had significantly reduced FCR, whereas those on the HT did not respond. From 69 to 105 d of age, turkeys on the HT that were fed the supplemented diets had significantly increased FCR, but there were no dietary effects among turkeys on the LT. There were no consistent diet effects on growth performance or carcass yields. Breast meat yields of turkeys on the LT were higher (33.5 vs 32.1%), and drum yields were lower (12.7 vs 13.0%), than those of turkeys on the HT. There were no significant amino acid balance x ambient temperature effects on processing yields. The hypothesis of this experiment could be rejected as production performance did not respond positively to extra supplementation of lysine, methionine, and threonine when subjected to an HT.
Aging↗
Effects of ambient temperature, arginine-to-lysine ratio, and electrolyte balance on performance, carcass, and blood parameters in commercial male turkeys.
The effects of ambient temperature (T; 15 C vs. 30 C from 6 wk of age onwards), dietary Arg:Lys ratio (Arg:Lys ratio; 1.00 vs. 1.25), dietary electrolyte balance (DEB: 164 vs. 254 meq/kg), and their interactions on growth performance and carcass yields of male turkeys were studied. The experiment was designed as a split plot, including T x DEB as the main plot and Arg:Lys ratio as the sub-plot, with 24 pens containing 35 male turkeys each. Feed consumption, BW gain, mortality, and processing yields were measured. Temperature had a clear effect on performance during all age periods. Feed intake was significantly lower for the high T group compared with the low T group (322.7 vs. 432.3 g/bird per day; P < 0.001). Consequently, BW gain during the experimental period (28 to 140 d of age) was significantly lower for the high T group compared with the low T group (14.54 vs. 18.74 kg; P < 0.001). Feed:gain during the period of 28 to 140 d of age was significantly lower for the high T group compared with the low T group (2.51 vs. 2.61; P < 0.001). The high dietary Arg:Lys ratio increased feed intake significantly until 56 d of age (200.6 vs. 197.6; P < or = 0.034). A high Arg:Lys ratio resulted in significantly higher BW gain until 98 d of age (10.03 vs. 9.84 kg; P < or = 0.024). The Arg:Lys ratio did not affect feed:gain throughout the experiment. Dietary electrolyte balance did not affect performance parameters. No consistent two- or three-way interactions were observed. Processing yields were only affected significantly by T, and not by Arg:Lys ratio or DEB main effects. High T resulted in lower cold carcass (73.2 vs. 74.9%) and breast meat yields (33.5 vs. 36.0%), and higher thigh (18.9 vs. 18.1%), drumstick (14.5 vs. 13.2%), and wing yields (11.7 vs. 10.6%) compared with low T. We concluded that growth performance is compromised by higher T, and altering the Arg:Lys ratio or DEB does not alleviate this impaired performance. Dietary Arg levels seem to be important when dietary Lys is marginal relative to the requirement.
Animal Feed↗
Classification and longitudinal examination of callused teat ends in dairy cows.
To examine the development of teat end callosity thickness and roughness in early lactation and to quantify cow factors of interest, a system to classify teat end condition was developed. A distinction was made between rough and smooth rings around the teat orifice. In addition, a classification of the degree of callosity was developed. Kappa coefficients for the repeatability of scoring by this classification system by different workers were 0.71 for teat end callosity thickness and 0.86 for teat end callosity roughness. The teat end callosity classification system was used for a longitudinal study with 40 cows during the first 14 wk of lactation. Models were built to predict teat end callosity thickness and roughness, machine-on time, and milk yield. For the response variables, teat end callosity thickness, machine-on time, and milk yield, the consecutive measurements appeared to follow a lactation curve model with a subject-specific general slope and intercept. Teat end callosity increased rapidly the first 8 wk. Cow factors such as days in milk, parity, machine-on time, and teat end shape were associated with the degree of teat end callosity, and the probability of the callosity ring to become rough. Teat end callosity thickness did not decrease within the 14-wk trial period for most teats. Pointed or round teat ends showed more callus than inverted teat ends. Longer machine-on time resulted in a higher probability of the callosity ring to become rough. Rear teats showed less callosity than front teats in this study.
Animals↗
[Veterinary assistance to dairy farms in the Netherlands: an assessment of the situation by dairy farmers].
A questionnaire-based study was conducted among 466 dairy farmers in the Netherlands. The study investigated the experiences and opinions of dairy farmers about veterinary herd health and production management programmes. The dairy farmers were selected at random, and thus some took part in such programmes whereas others did not. The questionnaire comprised general questions about the farm operation and specific questions about the herd health programme and the practice conducting it, as well as perceived advantages and disadvantages of the veterinary programme. Farmers who did not participate in such programmes were questioned about their reasons for not participating. Both groups were questioned about future perspectives and opportunities. The costs of the programme appeared to be a drawback for participation but not as much as perceived by the practices. According to farmers, programmes focus too much on curative aspects and too little on analysis or prevention, where the needs are. Farm areas not included in the programme are so far not yet covered by other institutions, contrary to the expectations of the veterinarians. In the future, the farmers would be willing to take part in similar or expanded programmes, provided that certain conditions, such as product definition, structure, planning, costs, are properly met.
Animals↗