Teat Damage Research Articles

Evaluation of selected biophysical parameters of the teat skin of dairy cows

The aim of the research was to assess transepidermal water loss (TEWL), epidermal hydration (EH) and teat skin pH in Holstein-Friesian (HF) dairy cows of various ages and with varying degrees of teat skin damage. The research was carried out on one farm in 3 groups of 18 animals each: B1 – cows in the 2nd or 3rd lactation with a teat damage score of 2; B2 – cows in the 5th or 6th lactation with a teat damage score of 3; and B3 – cows in the 5th or 6th lactations with a point assessment of teat damage of 4. The Burmeister classification was used (1). In each cow, the parameters were assessed four times throughout the summer. Measurements were performed using a 5-head Courage Khazaka Multi Probe digital camera with the Windows Adapter MPA 5 software (D-50829 Köln, Germany). The TEWL values were lowest in group B1 (average = 28.5 g/m2/h) and significantly higher in groups B2 (33.28 g/m2/h) and B3 (39.48 g/m2/h). The highest EH values were obtained in group B1 (24.85%), and they were significantly higher than those in groups B2 (15.63%) and B3 (15.39%). Skin pH values in all groups of cows ranged from 6.96 to 7.2. The research allowed us to conclude that TEWL, EH and pH are sensitive indicators of the condition of the epidermal barrier of the teat skin and its stability. The parameters tested in this study may be useful in clinical practice for monitoring the condition of teat skin and assessing the progress of skin lichenisation.

Effects of milking machine settings and teat liners on bovine udder health

The purpose of milking machines is to harvest milk at an optimum speed while maintaining cow comfort and preserving teat defence mechanisms against the invasion of mastitis pathogens, thus making machine settings critical in dairy herds. The various settings and combinations for milking machines were reviewed to enable operators to optimize them to preserve teat canal integrity and minimize mastitis. All databases of Web of Science and relevant websites were used to document machine settings and teat liners. All vacuum levels in milking systems need to be monitored. In addition, liners, milk yield, and automated cluster removal switch-point settings need to be regarded as bearing a risk of teat damage. They affect milking speed and vacuum levels at total, peak, and over-milking. An equilibrium should be reached between optimal milking speed and risk of teat damage. An increased switch-point setting shortens milking time and decreases overmilking and claw vacuum to preserve teat-canal integrity. Analysis of milk flow dynamics with a VaDia instrument highlights opportunities to improve milking protocols and equipment functions that align with the physiology of the cow. This knowledge can be applied on individual farms, in which herd milk yield, parlour layout, milking machine system, parlour management, and economics should be considered to obtain a balance between milking efficiency, udder health, and cow comfort. Standards for switch-point settings were identified in this review.

The effect of various automatic cluster removal switch-point settings on milking and overmilking duration and total, peak and overmilking claw vacuum in dairy cows

AbstractThis research communication describes the effect of three automatic cluster removal (ACR) switch-point settings on machine-on time, overmilking duration, and the mean, peak-flow and overmilking vacuums. The objective was to reduce the overmilking and milking time, attaining a lower mean claw vacuum during overmilking. In a randomised experiment, 25 cows were subjected to three ACR switch-point settings at flow rates of 0.840 kg/min, 0.630 kg/min and 0.504 kg/min each for 15 morning-milkings. Pre-milking preparations and cow comfort were observed and evaluated, showing evidence that the switch-point setting of 0.840 kg/ml denoted the least proportion of behavioural problems (1.1% ± 0.6) compared to the settings at 0.640 kg/ml (16.0% ± 2.2) and 0.504 kg/ml (9.4% ± 1.7). A VaDia device (Biocontrol) determined the machine-on time and vacuum levels at the claw, mouthpiece and pulsator chamber. The machine-on time varied from 290 ± 72.8 (mean ± sd) to 289 ± 64.4 and 303 ± 66.3 for the 0.840, 0.630 and 0.504 kg/min settings, respectively. Overmilking was shortened by 29.3% and 26.4% and the claw vacuum during overmilking was reduced by 3.7 kPa and 4.3 kPa when using the 0.840 kg/min switch-point setting, compared to the others. An increased cluster-removal milk flow threshold reduced both overmilking and vacuum level during overmilking, lowering the risk of teat damage. Adapting ACR switch-point settings offers a valuable opportunity to increase parlour efficiency and cow comfort in dairy herds.

SPECYFICZNE CECHY MLEKA OWCZEGO I JEGO WŁAŚCIWOŚCI PROZDROWOTNE W ZALEŻNOŚCI OD LICZBY KOMÓREK SOMATYCZNYCH

Sheep milk is a valuable product due to its properties and composition. It is richer in high-quality protein and contains more nutritional value compared to the milk of other ruminants. Raw milk is characterized by a lack of enzymatic activity and a lack of pathogenic microorganisms. Milk also has a high content of minerals. For this reason, sheep's milk is a good raw material for the dairy industry and the production of fermented milk drinks as well as cheese. During lactation, the content of individual milk ingredients and milk yield fluctuate, which translates into the nutritional value of the product. Also, the content of somatic cells in milk is significantly different between the peak and the end of lactation of animals. The increase in cellular elements is a major indicator of mammary gland infection. The cause of mastitis is bacterial infection or mechanical teat damage. Inflammation of the mammary gland is a serious problem for dairy farmers due to the health and economic aspects of this disease, which is the main cause of slaughtering ewes and the fall of many animals, as well as enforcing the cost of healing females, and the obtained milk is utilized. It is estimated that up to 60% of sheep in herds can suffer from asymptomatic mastitis, which is a serious problem for the dairy industry. That is why research is important to analyze the amount of somatic cells in milk.

Prevalence of sub-clinical mastitis and its association with milking practices in an intensive dairy production region of Uganda.

A cross-sectional study was conducted to investigate the risk factors for sub-clinical mastitis (SCM) in Mbarara District, an intensive dairy production region of Uganda where hand-milking is dominant. In 30 farms, herd-level milking practices and SCM prevalence were studied. The SCM prevalences were 68.6% (417/608, 95% confidence interval (CI): 64.9–72.2%) and 39.2% (946/2,411, 37.3–41.2%) at the cow- and quarter-levels, respectively. A preventive factor for SCM was cow calmness at the end of milking (OR: 0.20, 95%CI: 0.05–0.79, P=0.021); a risk factor was rough teat-end (OR: 1.75, 95%CI: 1.14–2.68, P=0.011). Good cow hygiene was negatively associated with environmental mastitis (P=0.002). Appropriate hand-milking practices that avoid teat damage are expected to reduce SCM in Uganda.

Long Term Benefits on Social Behaviour after Early Life Socialization of Piglets

Simple SummaryPig welfare is a societal concern, partly due to the intensive rearing conditions. One welfare concern is aggression between newly regrouped pigs. Aggression at weaning is reduced by putting several groups of piglets together when young; termed socialization. Information is missing about how socialization affects sow health and if the behavioural changes in piglets are long-lasting. We aimed to address these questions by studying sow udder quality and pig behaviour and growth in socialized and control groups. Pigs were socialized by either joining two litters (32 sows; 16 groups) at 14 days of age or not joining them (33 sows). At weaning, the sows of socialized groups had more udder damage than the controls. Socialized piglets had double the amount of bite injuries (skin lesions) than controls the day after socialization, but had 19% fewer skin lesions at regrouping at eight weeks old when injuries are more numerous and severe. At 11 weeks old, there was no difference between the groups. In a test for aggressiveness, socialized pigs attacked more often and quicker, showing greater confidence in agonistic skills. Socialization means additional work for farmers and may cause more udder damage, but has beneficial effects for pig behaviour and welfare at later regrouping.Early life socialization of piglets has been shown to reduce piglet aggression at weaning, but information on sow health and long-term benefits is lacking. We aimed to assess how socialization impacts sow udder quality and long-term pig behaviour and growth. At two weeks of age, 65 litters either experienced socialization with one other litter (SOC) or did not (control; CON). Sows (housed in farrowing crates) were scored for teat damage and piglets were observed for aggressive behaviour (resident-intruder test) and growth and skin lesions up to 11 weeks under conventional farm conditions (including weaning and regrouping). At weaning, SOC sows had more teat damage than CON sows (p = 0.04). SOC piglets had double the number of lesions 24 h post-socialization compared to the control (19 versus 8; p < 0.001). In the resident-intruder test, more SOC pigs attacked the intruder (SOC 78%; CON 66%; p < 0.01), and attacked more quickly (p = 0.01). During regrouping (week 8), SOC pigs had 19% fewer lesions (SOC 68; CON 84; p < 0.05), but three weeks later, groups did not differ. Growth was unaffected by treatment. Overall, socialized piglets seem to be equipped with greater confidence or agonistic skills, leading to fewer injuries from fighting up to at least six weeks after socialization.

Tick Prevalence and Associated Udder Damage and Mastitis on Cattle in Jimma Town, Southwestern Ethiopia

A cross-sectional survey was conducted to determine tick prevalence and their association with mastitis on 390 cattle at three communal grazing sites and two dairy farms from October 2008 to April 2009 in Jimma town. Ticks were collected from half body parts and udder and teats were examined on lactating cows and heifers to identify tick lesions and mastitis. Of total 3015 ticks in number collected, 3 genera and 5 species of ticks had been identified: Amblyomma cohaerens (44.94%), Amblyomma variegatum (31.11%), Boophilus decoloratus (18.97%), Rhipicephalus evertsi evertsi (3.08%) and Amblyomma gemma (1.9%). There was a significant variation with predilection site of tick species. A. variegatum, A. gemma and R. evertsi evertsi had a significance variation with age of the animal. B. decoloratus and R. evertsi evertsi had significance variation with breed of cattle. Udder, Brisket and Perineum were the predominant predilection sites for the tick species collected. R. evertsi evertsi was the only species prefer Ano-vulva region. Result on the immature ticks (larvae and nymphs) shows that, 63.47% Amblyomma, 35.75% Boophilus and 0.77% Rhipicephalus genera. Neck, Dewlap, Udder and Perineum were the main predilection sites of ticks on which the immature ticks were collected. Although (123) 31.6% of the sampled cattle had some degree of udder and teat damage, out of those cows and heifers with udder and teat damage (30) 24.39% was positive for mastitis. The tick species found on cattle with udder and teat damage were Amblyomma cohaerens (46.51%), Amblyomma variegatum (40.62%), Boophilus decoloratus (11.88%) and Amblyomma gemma (0.99%). There was a significance variation between study sites and breed of cattle on animals with mastitis. Tick infestations associated udder lesions, and mastitis is major problems in cattle and deserves further attention owning to their potential impact on milk production affecting food security.

English

&nbsp; Ticks are vectors of tick-borne diseases, cause teat damage and tick-worry. They are commonly controlled using conventional acaricides, which are expensive to the resource-limited farmers, making them to resort to alternative tick control materials. The objective of this study was to validate the acaricidal properties of various ethno-veterinary materials used by rural farmers in the Eastern Cape Province of South Africa.&nbsp;In vitro&nbsp;repellency and contact bio-assay models were carried out to determine the repellency and acaricidal properties of&nbsp;Ptaeroxylon obliquum, Aloe ferox&nbsp;Mill, Lantana camara&nbsp;L, Tagetes minuta,used engine oil and Jeyes fluid on&nbsp;Rhipicephalus sanguineus&nbsp;ticks. The optimum repellency of Jeyes fluid at concentrations of 76.8 and 100% lasted for 6 and 7 h, respectively. Tabard the reference product lasted for 4 h.&nbsp;P. obliquum&nbsp;(40%) repelled the ticks for 40 min. For the contact bio-assay, used engine oil,&nbsp;T. minuta&nbsp;oil (50%), Ektoban&reg;and Jeyes fluid (76.8%) caused tick mortality of more than 86%. This study reveals that the materials rural farmers use to control ticks vary in their efficacy. Jeyes fluid and used engine oil have acaricidal effect as the conventional acaricides whereas extracts of&nbsp;A. ferox,&nbsp;L. camara&nbsp;and&nbsp;T. minuta&nbsp;are not. &nbsp; Key words:&nbsp;Acaricides, ethno-veterinary materials, repellency,&nbsp;Rhipicephalus sanguineus.

Histological examination of non-lactating bovine udders inoculated with Lactobacillus perolens CRL 1724

The effect of intramammary inoculation of Lactobacillus perolens CRL 1724 on bovine udders at drying off was evaluated through histological examination of the canal and cistern tissues. The persistence of the strain in the udder 7 d post inoculation was also determined. Lb. perolens CRL 1724 was recovered from all mammary quarters and no clinical signs or teat damage were observed after inoculation of 10(6) cfu/ml. The udders showed a normal structural aspect and there were no modifications of the milk appearance. Lb. perolens CRL 1724 cells were evidenced on the surface of the epithelial cells of the cistern without causing any morphological modifications or cell alterations. Lb. perolens CRL 1724 produces a mild inflammatory reaction, characterized by recruitment of neutrophils to the epithelial zone and a slight hyperaemia into blood vessels. This preliminary study provides important information for further studies directed towards the inclusion of Lb. perolens CRL 1724 in the design of probiotic products for preventing bovine mastitis in non-lactating dairy cows.

Effect of different hand-milking techniques on milk production and teat treatment in Zebu dairy cattle

The aim of the study was to test three different hand-milking techniques ("pull down", "thumb in", and "full hand grip") and their effects on milk production and teat treatment. This is important since milk production in many tropical areas still rely on hand-milking. The study was carried out at a peri-urban farm in the Bobo-Dioulasso area in Burkina Faso. Twelve indigenous Zebu cows in early lactation were used in the study. The sequences of the treatments (hand-milking techniques) and the milkers were balanced for carry-over effects between successive periods and days, respectively. The sequences were constructed by using special Latin squares. Yield and composition of saleable milk was not affected by milking technique but there were differences between the milkers in milk yield. There was also a significant interaction for saleable milk yield between milker and milking technique. Hemoglobin in milk was measured as an indicator of teat damage. The hemoglobin content was numerically higher in post-milking strip milk samples than in saleable milk. It was concluded that the amount of milk removed depends mainly on the milker and how well the milking technique works for the individual milker. No effect of milking technique was observed on teat treatment.

Effects of intramammary inoculation ofLactobacillus perolensCRL1724 in lactating cows’ udders

Bovine mastitis is the most important infectious disease on dairy farms. Conventional antibiotic therapy is often unsatisfactory and alternative treatments are continually under investigation. Lactobacillus (Lb.) perolens CRL 1724 and Lactobacillus plantarum CRL 1716 were previously isolated from milk of dairy cows and selected according to their potential probiotic properties. In the present work the in-vitro capacity of Lactobacillus strains to adhere to bovine teat canal epithelial cells (BTCEC) and to inhibit and co-aggregate 14 mastitis-causing pathogens (MCPs) was investigated. The effect of Lb. perolens CRL 1724 after intramammary inoculation in lactating cows was evaluated through determination of clinical signs of mastitis, milk appearance, somatic cell counts and Lb. perolens CRL 1724 recovery from milk. Lb. perolens CRL 1724 was able to inhibit 12 of 14 MCPs (85·7%) in vitro, especially those considered to be major pathogens. In addition, Lb. perolens CRL 1724 co-aggregated with all of them. Lb. plantarum CRL 1716 was able to inhibit 7 of 14 MCPs (50%) in vitro and showed co-aggregation ability similar to Lb. perolens CRL 1724. Lb. perolens CRL 1724 showed a higher efficacy of adhesion to BTCEC (values of percentage of adhesion and adhesion index of 75% and 14·4, respectively) than Lb. plantarum CRL 1716 (37% and 7·4, respectively). Lb. perolens CRL 1724 was recovered from all mammary quarters and no clinical signs or teat damage were observed after the inoculation of 106 cfu/ml. The udders presented a normal aspect and there were no changes in the appearance of the milk. The results obtained will serve as the basis for further trials to evaluate the potential of Lb. perolens CRL 1724 to be included in a non-antibiotic formulation for the prevention of bovine mastitis.

Tick infestation, and udder and teat damage in selected cattle herds of Matabeleland South, Zimbabwe

A cross-sectional survey was conducted to determine tick infestation, and udder and teat damage in 286 lactating cows and heifers at six properties in the smallholder and commercial sectors in Gwanda district of Matabeleland South Province, Zimbabwe. Eight tick species were identified: Amblyomma hebraeum, Hyalomma truncatum, Hyalomma marginatum rufipes, Rhipicephalus evertsi evertsi, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus appendiculatus, Rhipicephalus zambeziensis and Rhipicephalus simus. Overall, 81.5% of the cattle were tick infested; prevalence of tick-infested cattle was significantly higher on communal land (93.8%) and recently claimed land (85.1%) than on commercial farms. The mean tick load on infested cattle on communal land was significantly higher than in the other two sectors. Although 53% of the sampled cattle had some degree of udder and teat damage, very few farmers (2.6%) treated their cattle for these conditions. Udder damage was ca. two times and three times, respectively, more likely to occur in cattle on communal land compared to cattle on recently claimed land and commercial farms. The occurrence of R. appendiculatus and R. zambeziensis indicate that the cattle population in the study area is at high risk of a theileriosis outbreak, a tick-borne disease that has not been reported from this area.

Tick control methods used by resource-limited farmers and the effect of ticks on cattle in rural areas of the Eastern Cape Province, South Africa

A survey to document tick control methods used by resource-limited farmers in the control of cattle ticks in the Eastern Cape Province of South Africa was conducted by interviewing 59 cattle farmers using structured questionnaires and general conversation. Information collected was on external parasites of cattle, their effects and their control methods. Ticks were reported to be a major problem causing diseases like anaplasmosis (89.8%), babesiosis (55.9%) and ehrlichiosis (16.9%), as well as wounds that predispose to screwworm infestation, tick worry and teat damage to cows troubling farmers in their farming enterprises. The main tick control methods were; acaricides provided by government, however 94.9% of the farmers interviewed were of the opinion that the dip wash is not effective in killing the ticks. As a result, farmers complement the government dipping service with their own initiatives like spraying with conventional acaricides (22%), household disinfectants such as Jeyes fluid (18.6%), used engine oil (10.2%), chickens (5.1%), manual removal (5.1%), and pouricides (1.7%). In addition, some farmers also use plants (6.8%), mainly the leaf of Aloe ferox and the bark of Ptaeroxylon obliquum. The study revealed ticks to be a major problem in the study area.

Effect of Abrasion of Teat Orifice Epithelium on Development of Bovine Staphylococcal Mastitis

The predisposing effect of teat damage on mastitis caused by staphylococci and the pathogenicity of Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus epidermidis were investigated with an experimental model. The study included three experiments in which the teat canal orifice of 5 cows was slightly abraded. Experimental and control quarters were challenged with a staphylococcal suspension, and the status of the quarters was monitored. Virulence of the staphylococcal strains was studied using a protein-binding test with 125I-labeled proteins (fibronectin, fibrinogen, vitronectin, collagen type I and II, and IgG). Abrasion on the teat orifice epithelium was a predisposing factor for staphylococcal infections. Teat canal infection or colonization developed in 93% of experimental quarters and in 53% of control quarters; IMI developed in 73% of experimental quarters, but in none of the control quarters. Quarter IMI developed more consistently when the contaminating agent was S. aureus. Staphylococcus hyicus was very effective in causing teat canal infections, but S. epidermidis appeared to be less infectious. The S. aureus strain had strong binding sites for most of the proteins tested. The S. hyicus and S. epidermidis strains showed no binding, or only very weak binding, which correlated with lower infection rates.

The effect of floor type in farrowing pens on pig injury. II. Leg and teat damage of sows.

Leg and teat damage were scored at farrowing and at weaning for 383 lactating sows in farrowing pens with different floor types. Both leg and teat damage were rare on all three straw-bedded, solid cement surfacings: sand/cement screed, fibrocem screed and latex screed. Sows on fully-perforated floors had a high incidence of leg abrasions and cut teats. On floors where only the rear third was perforated, leg damage, but not teat damage, was lower than on fully-perforated floors. On both fully and partly-perforated floors the incidence of leg and teat damage was higher on plastic-covered woven wire than on punched metal. The most common site for leg abrasions was on the hind foot but about 10% of sows on plastic-covered woven wire also had abrasions on the hock and lower hind leg. Abrasions of the forelimb were rare except on fully-perforated floors. Teat damage generally involved the fifth, sixth or seventh teat pairs. The incidence of leg and teat damage appeared unrelated to sow parity. The results reflect the slippery nature of the perforated floors.

The effect of floor type in farrowing pens on pig injury. I. Leg and teat damage of suckling piglets.

Abstract Knee and teat damage were scored for 1376 suckling piglets from 140 litters on six different types of floor surface. Both knee and teat damage were present from the day of birth, increased over the first week of life and then started to heal in the second and third weeks. Overall knee damage levels were low with 41% of piglets having no damage and only 11% having significant damage. Knee damage incidence and severity were worse on an old cement screed than on more recently laid cement, fibrocem or latex screeds. Damage on solid floors was related to their skid resistance value. Lowest levels of knee damage were observed on fully perforated floors of plastic-covered woven wire, but punched metal floors gave damage levels similar to solid floors. Teat damage also showed a low incidence overall, with 92% of males and 76% of females unaffected. Incidence and severity of teat damage were again significantly lower on plastic-covered wire than on other floor types. Knee and teat damage were not related to piglet birth-weight and had little effect on live-weight gain.

Influence of suckling by Friesian cows on milk production and anoestrus

The effect of time (morning or afternoon), intensity (three or four calves per cow), frequency Once or twice daily) and duration (1, 2, 4 or 8 weeks) of suckling on the performance of multiparous Friesian cows in early lactation was studied in four experiments. In each experiment there was a group of cows that were machine milked twice daily from calving. Milk production from sucked cows was greater during the suckling period than from machine-milked cows in the same period, but in no case was there any significant difference between suckling treatments. Increases in production during the 8-week suckling period ranged from 7.1 (P &gt; 0.05) to 19.4% (P&lt; 0.05), or from 75-21 8 kg. The extra milk produced by the cows sucked once daily went to the calves, and similar (P &gt; 0.05) quantities or significantly less milk (P&lt; 0.05) was produced at the alternate machine milkings compared with non-sucked cows in the same period. Regardless of suckling treatment in early lactation, the cows failed to show any carryover benefit. Lactation length and liveweight change in cows was unaffected by suckling treatment. The interval of post-partum anoestrus increased by about 6 days for each additional week of suckling. The average increase due to 8 weeks suckling in the four experiments ranged from 41-66 days. Teat damage increased with duration of twice-daily suckling, but had no effect on yields after sucking stopped. Teat damage of cows sucked once or twice daily to 8 weeks was similar. The incidence of mastitis was low in both sucked and machine-milked cows, and was not related to suckling treatment. Multiple sucking of Friesian cows in early lactation is a means of obtaining more milk from individual cows without incurring penalties in liveweight and body condition loss; it has no effect on post-weaning milk production.

The Epidemiology and Pathogenesis of Experimental Staphylococcal and Coliform Mastitis in the Mouse

The invasiveness of Staphylococcus aureus and Escherichia coli for the mammary gland of the mouse was compared by depositing the organism on the tip of damaged or intact teats in the presence or absence of suckling, and sampling the mammary glands for the deposited organism 48 h later. 83% of glands became infected following exposure to S. aureus in suckling mice with teat damage; under the same conditions 3% of glands exposed to E. coli became infected. 17% of glands became infected following exposure to S. aureus in non-suckling mice with damaged teats; under the same conditions 20% of glands exposed to E. coli became infected. Pregnant mice with damaged teats were susceptible to infection with E. coli (20% became infected) immediately prior to parturition and this level of infection could be achieved in suckling mice if damaged teats were repeatedly exposed to E. coli . Infections arising from exposure of teats to E. coli were histologically and clinically identical to those induced by inoculating approximately 20 organisms of E. coli directly into the mammary gland. The inoculation of 20 organisms of S. aureus directly into the mammary gland produced an acute reaction whereas infections resulting from exposure of teats to S. aureus were chronic. Colonization of the teat by S. aureus preceded the establishment of chronic mastitis, but E. coli infections resulted from the chance entry into the mammary gland of a few contaminating organisms. The difference in epidemiology between staphylococcal and coliform mastitis is emphasized.

Comparison of dairy and multiple suckled calf production with calf access restricted

The effects on animal performance were measured when machine milking was compared with restricted access suckling of four, three and two calves per cow, and when machine milking was alternated with restricted access multiple suckling. Calves were allowed access to cows twice daily, and supplementary grain feeding was provided to half the calves. A stimulus to milk and butterfat production from cows returning to machine milking after a period of suckling occurred, but was not significant. Cow breeding performance and liveweight changes were unaffected by the suckling treatments. Clinical mastitis did not occur during suckling in comparison with 36 cases of mastitis during machine milking. Teat damage in suckling cows in early lactation was the only cow health care problem of consequence, and was controllable by udder salves. The average daily liveweight gain to 140 days over all treatments was 0.735 kg. Grain supplementation pre-weaning increased liveweight gain from 0.71 kg to 0.76 kg day-1 (P &lt; 0.05). Calf health was excellent, apart from some nutritional diahorrhea in unsupplemented calves. Neither enteritis nor deaths occurred in calves pre-weaning.

Evaluation of an iodophor teat spray in the control of infections and cellular reactions in the udder.

A strictly controlled field trial was designed to assess the value of an iodophorpost-milking teat disinfectant in the prevention of new mastitis infections in a 132 cow herd. The disinfectant was applied by a hand spray, a method acceptable, effective, and less costly than conventional teat dipping methods. Only the left side of the udder was treated, the right quarters acting as controls. Dry-cow therapy and other methods of mastitis control were already practised, and no change in routine was introduced apart from half-udder teat spraying. Fifty-eight new cases of mastitis were found to occur on the teat-sprayed side, compared with 91 in the untreated quarters; 35 and 23, respectively, were clinical. No Group B streptococci existed in the herd, and the principal reductions were in Group C streptococci and coagulase-negative staphylococci, the percentages of which were halved. The percentage of coliform infections on the teat-sprayed side was, in contrast, doubled. The incidence of new clinical and subclinical disease without infection was in reverse ratio to that of infections, being 29-9 per cent higher in the quarters which were teat-sprayed. Analysis of cumulative CMT reactions from regular monthly surveys indicated that exponential cell-count values on each side of the udder were identical. Thus, while new infections were significantly reduced, overall cell counts were not, and there is clearly a need for further research into factors other than bacteria which may initiate teat damage and inflammatory changes in the udder.