Enquête éco-pathologique continue: facteurs de risque des mammites de la vache laitière I. Analyses multidimensionnelles sur données d'élevage.

An epidemiological study about mastitis in French dairy herds, supported by an ecopathological survey is described.The aim of this work was to explain variations of the annual frequencies of clinical mastitis in the farms studied and of milk somatic cell counts as predictive of the infectious status of the mammary gland. Milk cell counts were expressed as annual percentages of cell results < 2.10(5) cells / mL (0.2 CEL) and > 1.10(6) cells / mL (1.0 CEL) in each herd.Twenty-nine herds were studied from June 1979 to July 1981 (22 to 92 cows per herd, Normande and Pie-Noire breeds) and, for the first time, the influence of 88 variables upon clinical mastitis, 0.2 CEL and 1.0 CEL was performed by multidimensional methods.These analyses led to the evidence of two kinds of factors linked with mastitis occurrences or milk cell-counts:1) Not well defined factors: geoclimatic, racial, links between production traits, extra-mammary pathology, susceptibility to mastitis and cells-counts; to elucidate if they were factors really linked with mammary infections, a complementary analysis is described as necessary (cf. second part of this study).2) Risk or protective factors, which appeared as: - absence of at least one annual examination of the milking machine (risk factor for clinical mastitis) - udder washing with individual towels, associated with enough straw for bedding (protective factor against mastitis) - teat dipping (associated with low milk cell-counts)Other prophylactic methods appeared without any effect. In the discussion, main difficulties of an epidemiological approach to the mastitis problem are summarized. A convenient hygiene-prophylaxis interaction is necessary to control mammary infections in dairy herds.

Prostaglandin F2 alpha and prostacyclin imbalance in cows with placental retention: new findings.

The aim of this work was to investigate possible differences in peripheral blood concentrations of 13, 14 dihydro 15 keto PGF alpha (PGFM) and 6 keto PGF1 alpha (PGIM), between dairy cows retaining (RP) and not retaining (NRP) their placenta. Blood samples were collected 5, 30, and 60 minutes postpartum from 8 RP and 17 NRP cows. PGFM concentrations were significantly lower in RP cows than in NRP cows 60 minutes after birth (8156 pg/ml vs 12016 pg/ml; P less than or equal to 0.05). There was a significant rise of PGFM levels between 30 and 60 minutes in NRP cows (6225 pg/ml vs 12016 pg/ml; P less than or equal to 0.01), while in RP cows PGFM levels remained fairly constant along the period studied. No significant differences were found between RP and NRP cows regarding PGIM levels during this period although absolute values were slightly higher in RP cows. The PGFM/PGIM ratio was significantly higher 60 minutes postpartum in NRP cows than in RP cows (15.5 vs 8.8; P less than or equal to 0.01). This ratio increased significantly in NRP cows between 30 and 60 minutes (7.2 vs 15.5; P less than or equal to 0.01), a pattern not observed in RP cows. There was no correlation between PGIM and PGFM levels during the first 60 minutes postpartum in the NRP cows. However, the same correlation was significantly positive in the RP cows (r = 0.75; P less than or equal to 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

[Continuing eco-pathological survey: the objectives and their accomplishment, the choice and the typology of the herd]. / Enquête éco-pathologique continue: les objectifs et leur réalisation, le choix et la typologie des élevages.

The Continuous Eco-Pathological Survey (EEPC) is a prospective and longitudinal epidemiological inquiry, designed to provide data on the global and special pathology in ovine and bovine species, particularly in the dairy cow. The chief purposes of this survey are: to get a better knowledge of the clinical pathology, observed both by the farmer and the veterinarian if he is consulted and the subclinical pathology, detected by various blood tests on 25% of the adult females in each herd; to look on the possible relationships between the herd frequencies of the major disease, i.e. "pathological associations"; to confirm classical or find out new risk factors linked with the environment of the farms; to propose a global approach for the prevention of the main diseases. In this article, methods of choice for herds and animals, and characteristics of the farms studied are described, and the state of realization of the chief objectives of the work is analysed. Conclusion concerns the future of our global approach of the pathology in ruminants.

[Continuing eco-pathological survey: 6. Influence of zootechnical and space-time factors on some biochemical variables in the dairy cow]. / Enquête éco-pathologique continue: 6. Influence de facteurs zootechniques et spatio-temporels sur quelques variables biochimiques chez les vaches laitières.

Several hundred of blood samplings were performed on dairy cows in four French departments, from 1978 to 1982. They were used to analyse the effect of eight factors on the physiological variations of twelve biochemical variables. Only the blood withdrawal date related to calving date or milk production were able to explain more than 15% of the variance of free or total cholesterol or phospholipids.

[Continuing eco-pathological survey: 7. Epidemiological approach to postpartum mastitis in the dairy cow: descriptive study and typology of the herd]. / Enquête éco-pathologique continue: 7. Approche épidémiologique des mammites post-partum chez la vache laitière: étude descriptive et typologie des élevages.

In this study, post-partum mastitis are considered as an epidemiological entity because of their high frequency (20% of cases of mastitis are observed in the seven first days after calving). The rate increases in May-June-July and after the fourth calving. Characteristics of herds with high frequency of post-partum mastitis are the same that those from herds with high frequency of mastitis or metritis, their risk factors seeming to exert an effect on all infectious diseases. Among these factors, straw bedding quantity seems to be the more important one: a low quantity of straw, even in herds where prophylaxis against mastitis is largely used (teat dipping, dry cow therapy, disinfection), is a favouring factor for apparition of mastitis just after calving. On the contrary, use of individual towels, an abrupt dry cow therapy and a vitamin prevention during the last part of pregnancy, appear more favorable.

[Continuing eco-pathological survey: 4. Demonstration of pathologic associations in dairy cow stock: herd data]. / Enquête éco-pathologique continue: 4. Mise en évidence des associations pathologiques en élevage bovin laitier: données d'élevage.

Data concerning frequencies of 17 main diseases in 59 dairy farms from continual eco-pathological survey, are analyzed by classical regression test, principal components analysis and analysis of variance. Thirty-three statistical relations (positive simple correlations) are shown. Clinical mastitis and retained placenta are associated to nine diseases each, metritis, stillbirth and non-infectious foot disorders to six, dystocia and infectious foot disorders to four, pathology of calf and abortion to three, mammary edema and appetite disorders to two. Ovarian pathology, digestive disorders and teat lesions are "isolated", being associated to only one other disease. The pathological frequencies in dairy farms seem to change in the same way, indicating the existence of common risk factors, and leading to propose a global hygienic prevention. The pathological associations allow to definite some groups of dairy farms showing one or other dominant pathological complex. In the frame of our sample of dairy farms, two groups seem to be determined: one with calving disorders and calf pathology centred on retained placenta, the other with foot disorders, infectious and metabolic troubles, centred on mastitis, as dominant diseases.

[Continuing eco-pathological survey: 5. Demonstration of pathologic associations in dairy cow stock: individual data]. / Enquête éco-pathologique continue: 5. Mise en évidence des associations pathologiques en élevage bovin laitier: données individuelles.

The calculation of pathological association ratio (or relative risk) from two ways contingency tables, allowed to show numerous interrelationships between diseases of 1,205 dairy cows. The analysis concerns the animal during productive life, the lactation (all lactation mixed), a particular one (1st, 2nd, 3rd and more) and the beginning of productive life of cow (three first lactations). The relationships are discussed according to the level of calculation (animal, lactation, or beginning of life). There is some triangular relations: calving trilogy (dystocia-stillbirth-retained placenta), infectious trilogy (foul of the foot-metritis-mastitis), metabolic trilogy (appetite disorders-ketosis-digestive disorders), foot disorders trilogy (lameness-non infectious diseases of foot-foul of the foot). These pathological groups seem to depend from common risk factors (climate-feeding-cowshed hygiene-control of heat-age-culling policy-genetic factors-anatomical or physiological predisposition, animal size...), but, numerous interactions between groups are also shown, leading to consider pathology in farm like a complex entity.

[Continuous ecopathological survey. 1. Classification of the pathology observed in dairy cattle breeding]. / Enquête éco-pathologique continue: 1. Hiérarchie de la pathologie observée en élevage bovin laitier.

Observations were made during a continuous ecopathological survey on 3,216 dairy cows from 90 dairy farms and localised in six French departments, over a three year period (1978-1981). The pathology described for cows and their calves was classified according to the frequency of each disease and/or symptom. The reasons for culling as well as those for mortality were also classified. The pathology of reproduction and the mammary gland in the dairy cow and the digestive pathology and mortinatality of calves appear to be the major pathological problems.

[Continuous ecopathological survey. 2. Typology of dairy cattle farms with high and low fertility]. / Enquête éco-pathologique continue: 2. Typologie d'élevages de vaches laitières à bonne et à mauvaise fertilité.

Management characteristics were analysed in two groups of dairy herds (20 to 60 cows per herd) during a continuous eco-pathological survey, in relation to high and low fertility. 59.8% of the cows from the eleven high fertility herds were successfully inseminated at first service and 11.4% of the cows inseminated for the first time more than 40 days post-partum required 3 or more services. The corresponding values were 51.1 and 25.6% for the ten low fertility herds. Other reproductive criteria (calving-first service interval, disturbed oestrus cycles), which more depend on the reproduction management, were not different between the two groups. Feeding system greatly varied in the low fertility group. Frequent changes in diet composition, a longer period of "green" forages distribution (crucifers, grass silage) as well as less utilisation of concentrates are some of the reasons which can explain the low fertility. Calving occurred mainly from February to April in low fertility herds, at the transition from winter diets to grazing. Milk production was lower, 4 580 kg per cow and per year vs 5 520 kg for high fertility group. Milk production falls were more frequent and Holstein semen was less used. Tied housing conditions, and higher incidence of Fasciola hepatica and abomasal mematodes characterised low fertility herds; inversely, the clinical pathology appeared to be less frequent in this group. Soil manganese concentration was lower (16.3 ppm) in the low fertility group as compared to the other group (30.9 ppm); this could be explained by less schistose rocks where the low fertility farms are localized. In conclusion, the risk factors associated with low fertility may be attributed to: the composite system of feeding in addition to the use of "green" forages, a lack of proper programming with regards to the season of calving, and the high frequency of parasitic infestations, with special reference to liver fluke.

[Probable conditioned prostaglandin deficiency in cows with ovarian cysts (author's transl)]. / possibilité d'une carence conditionnée en prostaglandines chez les vaches porteuses de kystes ovariens.

Blood and ovaries have been collected monthly for one year from 1358 cows at the slaughter-house. 4.4% of the cows presented cystic follicle ovaries (follicle with a diameter greater than or equal to 25 mm) and 5.7% presented cystic corpus luteum (internal cavity with a diameter greater than or equal to 10 mm). Analysis of fatty acid composition of red blood cells lipids has shown that in cows with cystic follicles (P less than 0.001) and in cows with cystic corpus luteum (P less than 0.01), the proportions of omega 3 family polyunsaturated fatty acids were higher than in normal cow. The sigma omega 3/ sigma omega 6 ratio was also higher (P less than 0.001) for cows with both types of ovarian cysts, particularly in spring, summer and autumn. An alimentary etiology of ovarian cysts pathogeny could be an increased intake of these fatty acids which are more abundant in young grass. The omega 3 polyunsaturated fatty acids are known to be inhibitors of the synthesis of PgF2 alpha which is involved in ovulation and luteolysis.

[The control of animal diseases in france during the last fifteen years, as it appears throught the eradication of bovine tuberculosis. proposals for the future (author's transl)]. / La lutte contre les maladies animales en France au cours des 15 dernieres années vue au travers de la prophylaxie de la tuberculose bovine. Propositions pour l'avenir.

In the general outline of the success, on a national scale, of the eradication of bovine tuberculosis in France up to 1974, we have tried to find out the factors which could explain the differences, sometimes important, between French departments in the efficiency of this eradication. We have selected twenty seven parameters distinctive of each of the 74 departments having more than 50 000 bovine under the control of State Veterinary service. These parameters describe 1) tuberculosis infection rates of animals and herds, at three periods; 2) some structural characteristics of bovine production; 3) sanitary environment (veterinary practicioners, State Veterinary service, breeders association for sanitary protection). Statistical analysis by principal components show that department infection rate decreases as the first three factors evidenced by this analysis vary positively; they are: 1) "Sanitary Consciousness", which is defined both by the important of bovine production and by precociousness in developing prophylactic measures, these two factors being independent. 2) Specialization in bovine production, characterized by the percentage of young animals reared in the herd and by the proportion of grass produced by ley. 3) Intensity of sanitary environment. These three factors, which are interlinked to various degrees, control respectively 25%, 13% and 13% of the total variance. A complementary analysis of the data suggest that the efficiency of eradication could be improved by a better knowledge of the movement of breeding animals between the departments, and by a more careful recording, in some instances, of infected animals in slaughter hourses. When the importance of a herd increase sanitation of tuberculosis in infected herds is less readily achieved and brucellosis abortion rate increases. At the departement level, efficiency of eradication is not correlated to the expenses of prophylaxy. For the development of an integrated sanitary policy, taking into account such non specific factors as those exemplified in the study could help to a better control of animal diseases, in parallel to the desirable improvement of the specific means of combatting each disease.

Level of linoleic acid in pericardial lipids of Charollais cows with and without ovarian cysts.

The content of linoleic acid, a precursor of prostaglandins, in pericardial lipid store is higher in cows with normal ovaries than in cows with cystic ovaries.

[Delay and magnitude of plasma and bone responses and of stable, residual, leachable hair fractions to two different levels of K, Na, Ca, Mg, P intake in rat (author's transl)]. / Latence et amplitude des résponses plasmatique osseuse, et des fractions pilaires labile, stable et résiduelle a deux niveaux d'apport alimentaire en K, Na, Ca, Mg, P chez le rat

Two groups of 20 adult female rats are fed ad libitum with two diets differing in K, Na, Ca, Mg, P content, being for the first diet (in g/kg) : 14.9, 0.5, 6.3, 0.82, 1.25, respectively, and for the second : 1.6, 8.3, 2.4, 0.17, 5.76, respectively. Five rats of each group are killed after 1, 2, 3, 4 months. This study compares the delay and magnitude of plasma and bone responses and of three different hair fractions to the two levels of intake. Hair is not clipped in order to estimate the delay in response of already grown hair to mineral intake modification. The three following hair fractions are analyzed : a) leachable fraction, determined in the solution used for washing hair (equal parts water-ethanol-ether) ; b) stable hair fraction, determined in hair obtained after the previous washing ; c) residual hair fraction, determined in hair washed with a non-polar detergent. The following results are observed : 1) K : A plasma variation is obtained as early as month 1 (P less than 0.005). The leachable fraction is modified from month 3 (P less than 0.001) and the stable hair fraction on month 4 (P less than 0.025). 2) Na : There is no variation at the plasma level. The leachable fraction response appears as early as month 1 (P less than 0.001) and the hair stable fraction at month 2 (P less than 0.025). 3) Ca : There is no variation at the plasma level. The leachable (P less than 0.025) and hair stable (P less than 0.01) fractions show a response from month 3. 4) Mg : A rapid and intense variation is observed at the plasma level as early as month 1 (P less than 0.001). The hair stable fraction shows a response at month 2 (P less than 0.05) and the leachable and residual fractions at month 3 (P less than 0.05). Bone Mg is modified as early as month 1 (P less than 0.005). 5) P : Plasma response at month 4 (P less than 0.05) is weak and late. An important variation is observed from month 2 in the leachable fraction (P less than 0.005) and at month 3 in the hair stable fraction (P less than 0.005). Residual hair fraction provides no valuable information. Consequently, the more common method of washing hair with a detergent should be excluded, at least for the nutritional exploration of the minerals involved in this study.

[Influence of protein intake on plasma and hair leachable urea in the rat (author's transl)]. / Influence de l'apport protéique alimentaire sur l'urée plasmatique et l'urée pilaire labile chez le rat

Three groups of 13 adult female rats received daily for two months 23 g per rat of three synthetic isoenergetic feeds containing respectively 5, 15, 25 p. 100 casein. Plasma urea was measured weekly. Hair leachable urea and soluble dry matter were measured, at the end of the experiment, on hairs regrown after an initial clipping, in a solution obtained by washing 1 g of hair in 50 ml of HCl 0,01 N under mechanical shaking. Mean plasma urea values for the whole experiment for the three groups were 0.27, 0.38, 0.45 g per liter; differences between all groups were highly significant; however differences for the 15 and 25 p. 100 casein groups were not significant for the last three weeks. Hair leachable urea and hair soluble dry matter values were respectively 0.35, 0.80, 1.02 mg/g of hair and 20.4, 24.0, 26.0 mg/g of hair. A positive correlation links hair urea to hair dry matter (r=0.76, p less than 0.001). When hair urea is expressed in per cent of soluble dry matter, the respective values for the three groups are 1.90, 3.42, 3.95. Differences between the 5 p. 100 casein group on the one hand and the 15 and 25 p. 100 casein groups on the other are highly significant (p less than 0.001).

[Time and level of response of plasma, liver bone, leachable and stable hair fractions to copper deficiency and loading in the rat (author's transl)]. / Carence et surcharge alimentaire en cuivre chez le rat: réponses plasmatique, hépatique, osseuse, pilaire

One group of 20 adult female rats was fed ad libitum for four months with a synthetic regime containing less than 1 p.p.m. Cu. A second group received the same regime, supplemented with Cu and containing 87 p.p.m. on the 1st month, 109 p.p.m. in the 2nd and 3rd and 158 p.p.m. in the 4th month. Hairs were not clipped at the beginning of the experiment. Five rats of both groups were killed at the end of each month and Cu was determined in blood, liver, femur, and hair. Hair was washed with a water-ethanol (I/I/I) solution for 30 minutes under mechanical shaking, and Cu was determined in the washing solution (leachable copper) and in hair (stable copper). No clinical symptoms of Cu deficiency were observed. However there was an early and important drop (p less than 0.001) in blood and liver copper as early as the first month, which continued until the end of the experiment. Stable hair Cu dropped slightly on the first month (p less than 0.005) and continued to do so on the following three months (p less than 0.001). Hair leachable Cu and bone Cu were unaffected by the deficiency. Liver Cu increased at the 158 p.p.m. level of intake on the fourth month.