Efficacy of non-antibiotic treatment options for digital dermatitis on an organic dairy farm.

The objective of this study was to evaluate the efficacy of two non-antibiotic treatment options for digital dermatitis (DD) on an organic certified dairy farm. A randomized clinical trial was conducted using 70 multiparous Holstein cows with an early DD lesion at a USDA certified organic dairy farm in Northern Colorado, USA. Cows were enrolled in the study based on the presence of early DD lesions (scores M1 and M2) and randomly assigned to one of three treatments: (1) topical application of copper sulfate and iodine (CUI); (2) topical application of honey and iodine (HOI); and (3) control subject to no treatment (CON). Cows were evaluated at enrolment and on days 3, 12, 28, and 120 post treatment for pain and lesion size and received a locomotion and a lesion score. Cure was defined as the transition from active to non-active stages (M1/M2 to M0 or M4). The formulations had variable effects on the treatment of DD. The cure rate was numerically higher for CUI on all follow up days. The proportion of cows experiencing pain on d3 after treatment was greater in CON, followed by HOI and CUI. However, this proportion increased in HOI during the follow up period. The CUI group had a greater reduction in lesion size and larger lesions persisted in HOI. Non-antibiotic treatment formulations were partially effective in the treatment of DD in organic dairy cows: The two non-antibiotic formulations resulted in an earlier transition to mature lesions compared with the control group. The CUI combination was the most effective treatment in reducing lesion size, pain, and lameness in affected cows. However, this combination had short-term efficacy, which did not persist throughout the duration of the study. The HOI combination produced only transient reduction in lesion size.

Seasonal incidence of lameness and risk factors associated with thin soles, white line disease, ulcers, and sole punctures in dairy cattle.

Lameness is a multifactorial condition with many causes. In this study, cow lifetime records were used to quantify the incidence of specific lameness-causing lesions and investigate factors associated with those lesions. Of primary interest were the effects of seasonality and the effects of thin soles (TS). Thin sole-induced toe ulcers (TSTU) occurring adjacent to the white line in the apical portion of the weight-bearing surface were distinguished from white line disease (WLD) occurring in the region of the abaxial heel sole junction. Sole (SU), heel (HU), and toe (TU) ulcers; TS; sole punctures (SP); leg injuries (INJ); and other (OTH) lesions (e.g., infectious diseases, laminitis, unclassified hemorrhage) were also considered. Data were collected from May 2004 through October 2007 and included records for 4,915 cows of which 1,861 had at least one recorded lameness event. Of these, 20% were TSTU, 20% OTH, 16% SU, 13% TS, 10% WLD, 8% HU, 6% INJ, 4% SP, and 2% TU. Annual incidence risk for lameness was 49.1%. Overall incidence rate for lameness was 1.41/1,000 cow-days, and rates for all lesions were highest in the summer. As parity increased, so did incidence rates for TS, SU, WLD, HU, and INJ. For TS, TSTU, and WLD, incidence rates were lowest in early lactation (16 to 60 DIM), whereas for SU, HU, TU, incidence rates were highest in mid lactation (61 to 150 DIM). Cox proportional hazard models for TS, TSTU, WLD, SU, HU, TU, and SP included age and year of first calving and milk production capacity. Prior/concurrent lameness events, season, parity, and stage of lactation were included as time-dependent effects. Prior/concurrent TS increased the hazard for all other lesions, particularly TSTU, and HU. Having any other prior claw lesion also increased the hazard for all lesions. Hazard was highest in summer for all lesions except TU. Stage of lactation was a significant effect in hazard of TSTU, which was lowest in mid lactation (61 to 150 DIM).

Pathogenesis and Treatment of Sole Ulcers and White Line Disease.

Sole ulcers and white line disease are 2 of the most common claw horn lesions in confined dairy cattle. Predisposing causes include unbalanced weight bearing, and metabolic, enzymatic, and hormonal changes. The white line serves as the junction between the sole and axial and abaxial wall. It is vulnerable to trauma and separation, permitting organic matter to become entrapped. Colonization contributes to retrograde movement of the infection to the solar and perioplic corium, where an abscess forms resulting in pain and lameness. Successful treatment requires an orthopedic foot block to the healthy claw and corrective trimming of the lesion.

Traumatic Lesions of the Sole.

Traumatic lesions of the sole are a common cause of lameness in beef and dairy cattle. This article provides a brief description of traumatically induced conditions with specific attention to underlying causes, treatment, and prevention. Lameness, traumatic lesions of the sole, sole punctures, thin soles, thin sole toe ulcers, toe tip necrosis syndrome, and toe abscesses are discussed.

The Impact of Lameness on Welfare of the Dairy Cow.

The five freedoms offer a framework for discussion of lameness and its impact on the welfare of cows. Altered feeding behavior is a cause of reduced body condition, smaller digital cushion, and lameness. Providing a comfortable environment is critical to recovery and welfare. Pain associated with injury or disease of feet or legs is manifested by lameness. Pain management is an important part of therapy. In cases of severe lameness, euthanasia may be preferred. Lameness interferes with an animal's ability to exhibit natural behaviors by altering lying time, social interaction, ovarian activity and estrus intensity, and rumination behavior.

An Update on the Assessment and Management of Pain Associated with Lameness in Cattle.

Lameness affects the cattle industry via both economic losses and welfare considerations. In addition to production deficits, the pain and distress associated with lameness have been documented. Evaluation and prevalence of lame cattle are among the primary factors in third-party welfare audit programs. Mean lameness prevalence in herds has been reported to be as high as 36.8%, although a less than 10% prevalence of lame cattle was reported by some producers. Note that lameness is usually underreported by producers compared with independent observers, potentially because of a decreased sensitivity in detecting lame cattle.

Sensitive method for intraoperative roentgenograms.

A new technique using mammography film has been developed. A portable x-ray machine and mammographic film has been used to obtain excellent intraoperative radiographs of renal calculi. The kidney is exposed through a flank incision. The film is cut to a size and shape that will permit an easy fit behind the kidney. Exposed film is developed in an automatic processor. This technique has facilitated location and removal of small calculi and faintly opaque calculi. Uric acid stones have been demonstrated in vitro. It is an inexpensive technique that requires no special equipment.

Use of sodium nitroprusside and dopamine hydrochloride in the postoperative cardiac patient.

Effective postoperative nursing care of the cardiac surgery patient receiving combined drug infusion of dopamine HCl and SNP requires awareness of many critical factors. Among these are: (1) understanding of cardiac physiology with emphasis on the concepts of myocardial oxygen consumption vs. availability; (2) basic pharmacologic functions of dopamine HCl and SNP, both singly and combined; (3) importance of maintaining intravascular volume at optimum levels; and (4) awareness that constant nursing observations and reassessments are essential.

Balance and serum concentration of biotin in sheep fed alfalfa meal-based diets with increasing level of concentrate.

The objective of this study was to test the hypothesis that serum biotin concentration and biotin balance (consumed - [urinary output + fecal output]) measured as total avidin-binding substances (biotin + biotin metabolites) are responsive to changes in the proportions of dietary alfalfa meal and concentrate fed to sheep. Eight sheep (initial BW = 40 kg) consumed a pelleted alfalfa meal-based diet that had 95:5, 48:52, 23:77, or 9:91% alfalfa meal:concentrate ratios (DM basis) in a replicated 4 x 4 Latin square design with 20-d periods (10 d of acclimation, 7 d of adaptation, and a 3-d collection period with jugular blood drawn on the last day). Replacing alfalfa meal with concentrate in the pelleted diets decreased dietary concentrations of biotin proportionally. As the percentage of alfalfa meal in the diet decreased, there was a linear decrease in daily DM intake (1,128 to 901 g of DMI/d; P < 0.01), with a linear (P < 0.01) and quadratic (P < 0.01) increase in the apparent total-tract DM digestibility of diets (51.0 to 80.0%). The biotin consumed decreased with alfalfa meal proportion in the diet (linear, P < 0.01). Both fecal biotin concentration (linear, P < 0.01) and fecal biotin output (quadratic, P < 0.05) increased, reaching peaks at 23% alfalfa meal. Fecal biotin output was not correlated with biotin intake, DMI, or intake of digestible DM. Mean urinary output, urinary biotin concentration, urinary biotin output, and serum biotin concentration were not affected by treatments. Means of biotin balance were negative and revealed the same trends among treatments as did fecal output. Biotin balance was a quadratic (P < 0.05) function of decreasing alfalfa meal in the diet, with more negative values at the alfalfa meal:concentrate ratio of 23:77. Results suggest that the greatest synthesis of biotin in the total digestive tract occurs with diets of either 52 or 77% concentrate for sheep; however, research addressing the significance of biotin metabolites on biotin balance and plasma biotin pool is needed.

Effects of source and washing of erythrocytes on growth of bacterial pathogens from the bovine mammary gland.

Effects of source and washing of RBC on quantitative growth and hemolytic zone sizes of common bacterial pathogens of the bovine mammary gland were evaluated. Blood samples used to prepare the blood agar media were obtained from 10 adult dairy cows, 10 dairy calves, and 10 sheep. Hemolytic zone sizes produced by Staphylococcus aureus were significantly (P less than 0.01) larger on blood agar prepared with washed RBC than on blood agar prepared with nonwashed RBC, regardless of RBC source. With the exception of Corynebacterium bovis, growth of all bacteria was equivalent or significantly higher on medium prepared with washed RBC, compared with that on medium prepared with nonwashed RBC, regardless of RBC source. Significantly higher numbers of C bovis (P less than 0.01) and Streptococcus agalactiae (P less than 0.01) were isolated on medium prepared with washed cow RBC. Significantly higher numbers of Str uberis (P less than 0.01) and S aureus (P less than 0.05) were isolated on medium prepared with washed sheep RBC and washed calf RBC, respectively. Growth of Escherichia coli was not affected by the RBC source. Seemingly, RBC used in the preparation of medium should be washed. The source of RBC, as well as inter-animal variation, also should be considered in the quality control of medium.

Efficacy and safety of clorsulon used concurrently with ivermectin for control of Fasciola hepatica in Florida beef cattle.

The safety and anthelmintic efficacy of clorsulon (7 mg/kg of body weight, orally) given concurrently with ivermectin (0.2 mg/kg, subcutaneously) for control of Fasciola hepatica were evaluated in 75 crossbred beef cattle. Twenty-three control animals were given only ivermectin. Fluke egg counts were significantly lower (P less than 0.0001) in clorsulon-treated animals by day 14 after treatment than before treatment (base line) and were significantly lower (P less than 0.005) after treatment in clorsulon-treated animals than in controls. There was no significant change in fluke egg counts of controls after treatment. The efficacy of clorsulon in reducing F hepatica egg counts was 99%. Clorsulon showed poor efficacy against paramphistomes. Adverse reactions were not observed.

Efficacy of amoxicillin trihydrate for the treatment of experimentally induced foot rot in cattle.

Twenty holstein heifers were intradermally inoculated in the interdigital skin with a suspension containing Fusobacterium necrophorum and Bacteroides melaninogenicus to induce acute foot rot. Lesions, lameness, and swelling were evaluated during the study, using a subjective scoring system. Rectal temperature, species and number of bacteria isolated, and change in body weight were monitored throughout the study. Ten heifers (treated) were given amoxicillin trihydrate (10 mg/kg of body weight, IM) for 5 days, beginning at the onset of lameness. The remaining 10 heifers (controls) were given physiologic saline solution IM. Treated heifers had less severe lesions and greater weight gain than did control heifers. Rectal temperatures of treated heifers did not differ significantly from those of control heifers. It was concluded that administration of amoxicillin trihydrate early in the course of acute foot rot may reduce the severity of lesions associated with foot rot in cattle.

Efficacy of oxytetracycline for treatment of papillomatous digital dermatitis lesions on various anatomic locations in dairy cows.

OBJECTIVE: To evaluate efficacy of topical treatment with oxytetracycline solution among dairy cows with papillomatous digital dermatitis (PDD) lesions on the interdigital cleft, heels, or dewclaw. DESIGN: Clinical trial. ANIMALS: 70 dairy cows from a single herd. PROCEDURE: On the basis of anatomic location of PDD lesions, cows were allocated into 1 of 3 groups (interdigital cleft [n = 14], heels [30], or dewclaw [26]) and treated topically with oxytetracycline solution. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion size scores were recorded. RESULTS: On the basis of pain and lesion size scores, oxytetracycline appeared significantly less effective among cows with lesions on the interdigital cleft than for cows with lesions on the heels or the dewclaw. Number of cows with signs of pain or visible lesions after treatment was significantly higher for cows with lesions on the interdigital cleft than for cows with lesions on heels or the dewclaw. CONCLUSIONS AND CLINICAL RELEVANCE: Anatomic location of PDD lesions has an effect on the efficacy of topical treatment with oxytetracycline solution in dairy cows affected with PDD. Cows with lesions on the interdigital cleft were less likely to respond to treatment, compared with cows with lesions on the heels or the dewclaw.

Comparison of topical application of oxytetracycline and four nonantibiotic solutions for treatment of papillomatous digital dermatitis in dairy cows.

OBJECTIVE: To compare efficacy of topical treatment with oxytetracycline solution or 1 of 4 nonantibiotic solutions among dairy cows with papillomatous digital dermatitis (PDD). DESIGN: Randomized field trial. ANIMALS: 66 cows in a single herd. PROCEDURE: Cows were randomly assigned to be treated with oxytetracycline solution; a commercial formulation of soluble copper, peroxide compound, and a cationic agent; 5% copper sulfate solution; acidified ionized copper solution; hydrogen peroxide-peroxyacetic acid solution; or tap water. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion scores were recorded. RESULTS: On the basis of pain and lesion scores, oxytetracycline and the commercial formulation appeared equally effective for treatment of PDD and significantly more effective than 5% copper sulfate solution, acidified ionized copper solution, hydrogen peroxide-peroxyacetic acid solution, and tap water. Proportions of cows with signs of pain or visible lesions after treatment were significantly lower for cows treated with oxytetracycline or the commercial formulation than for cows in the other groups. CLINICAL IMPLICATIONS: Oxytetracycline and a commercial formulation of soluble copper, peroxide compound, and a cationic agent appeared to be effective for treatment of PDD in dairy cows.

Mycoplasmal mastitis in a dairy herd.

In October 1985, mycoplasmas were isolated from bulk tank milk samples in a large Florida dairy (greater than 1,400 lactating cows). At that time, measures to isolate and control the spread of infection were instituted. In an initial screening test, Mycoplasma bovis was isolated from 21 of 153 milking string samples (milk from all quarters of 10 cows/string). Composite quarter milk samples from all quarters of every individual lactating cow in the herd were obtained for culture in November 1985 and December 1985. In October, 88 of 1,535 (5.7%) cows were identified as Mycoplasma-positive. An additional 31 Mycoplasma-infected cows were identified in December. The dairy elected to maintain the infected cows in a separate Mycoplasma-positive subherd, which would be milked at the end of each milking session. Seven additional Mycoplasma-positive cows were identified at initiation of lactation. All newly identified infected cows were transferred to the Mycoplasma-positive subherd. After segregation of Mycoplasma-positive cows, bulk tank milk samples obtained routinely from the main herd remained culture negative throughout the study. From February 1986 to October 1986, quarter milk samples were obtained monthly from cows in the Mycoplasma-positive subherd. Any cow that developed clinical mastitis or substantial decrease in milk production was, at the discretion of the herdsman, culled. Of the 126 cows in the subherd, 22 (17.5%) were culled for mastitis, 35 (27.8%) were culled for low production, and 9 (7.1%) were culled for other reasons. Of the remaining 60 cows, 16 (12.7% of the 126 cows) were Mycoplasma-positive on the basis of results from one or more samples obtained after February 1986.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of lameness on the calving-to-conception interval in dairy cows.

OBJECTIVE: To examine the relationship between lameness and the duration of the interval from calving to subsequent conception in lactating dairy cows. DESIGN: Cohort study. ANIMALS: 837 dairy cows. PROCEDURE: Cows affected with lameness were classified into 1 of 4 groups on the basis of types of disease or lesions observed, including foot rot, papillomatous digital dermatitis, claw lesions, or multiple lesions. Cows not affected with lameness were classified as healthy. Time from calving to conception was compared between lame cows and healthy cows. RESULTS: 254 (30%) cows were affected with lameness during lactation. Most lame cows (59%) had claw lesions. Lame cows with claw lesions were 0.52 times as likely to conceive as healthy cows. Median time to conception was 40 days longer in lame cows with claw lesions, compared with healthy cows. Number of breedings per conception for lame cows with claw lesions was significantly higher than that for healthy cows. CONCLUSION AND CLINICAL RELEVANCE: Claw lesions were the most important cause of lameness, impairing reproductive performance in dairy cows, as indicated by a higher incidence of affected cows and a greater time from calving to conception and a higher number of breedings required per conception, compared with healthy cows.

Efficacy of febantel paste against naturally acquired gastrointestinal nematodes of cattle.

Twenty calves with naturally acquired gastrointestinal nematode infections were assigned to 10 replicates of 2 calves each and were treated with febantel paste (5 mg/kg of body weight, PO) or an equivalent volume of paste vehicle (control calves). Adverse reactions were not observed after febantel treatment. At necropsy, gastrointestinal nematode counts in febantel-treated calves, compared with control calves, were reduced by over 99% for all major species except Trichuris discolor, counts of which were reduced by only 69%. Counts of gastrointestinal nematode eggs in feces of febantel-treated calves were reduced by 100% after treatment.

Mastitis in heifers.

Udder health is typically overlooked but critically important in heifers. Mastitis pathogens of the contagious as well as environmental groups have been implicated in mastitis in heifers. Procedures considered for control of heifer mastitis include prepartum treatment in primigravid heifers, separating preweaned calves to prevent suckling, fly control, and segregation of pregnant heifers from dry cows. Further investigation is needed before general recommendations can be made relative to prepartum treatment of primigravid heifers. An improved understanding of the epidemiology and pathogenesis of heifer mastitis will aid in expanding and improving control measures.

Functional and corrective claw trimming.

Foot care and claw trimming require proper systems for restraint, sharp knives and trimming equipment, and an understanding of the biomechanics of weight bearing and hoof overgrowth in cattle. The objective of functional claw trimming is to correct hoof overgrowth, thereby re-establishing appropriate weight bearing within and between the claws of each foot. Traditional trimming methods fail to achieve these objectives. Corrective trimming procedures are applied to horn lesions affecting the claw capsule. Primary objectives of corrective trimming are to adjust weight bearing to provide rest for diseased claws and to remove loose horn and hard ridges that may cause further injury to the corium. The application of a foot block to the healthy claw is a valuable aid in foot care when corrective trimming alone is insufficient to provide needed relief from weight bearing. Finally, the use of topical treatments under a bandage is controversial. It is recommended that caustic treatments be avoided and that the use of a bandage be limited to conditions requiring hemostasis or when operators are committed to their removal within a period of 2 to 5 days depending on the level of environmental contamination.

Abnormalities of hoof growth and development.

The normal development of the horn capsule (epidermis), with its dermal support (corium), is described. Abnormalities of horn growth may be caused by changes in blood flow (laminitis), the biomechanics of weight bearing, heritable developmental conditions, and other changes of unknown cause.