Päivi J Rajala-Schultz

• DVM, PhD, Dipl. ACVPM
• Professor (Full) at The Ohio State University

The worldwide problem of increasing dairy cow mortality is widespread in modern production systems, it causes economic losses, and indicates problems with herd health and welfare. Most studies on causes of dairy cow mortality are limited as they are based on secondary register data, or questionnaires for producers or veterinarians, and neither necr...

Antibiotic dry cow therapy (aDCT) at the end of lactation is an effective mastitis control measure. Selective dry cow therapy means that only infected or presumed-infected cows are treated, instead of aDCT being used as a treatment for all cows. Because antibiotic resistance poses a global threat, livestock production is under increasing pressure t...

Mastitis remains the most expensive disease of dairy cows, and antibiotic dry cow therapy (DCT) at dry-off is an important part of mastitis control. Regardless of the infection status, blanket DCT is administered to all quarters of all cows, which is controversial due to the worldwide problem of antimicrobial resistance. Even though selective DCT o...

The cessation of milking at the end of lactation is a routine management practice in dairy herds, and the importance of the dry period for milk production and udder health, has long been recognized. Among countries and herds, drying-off practices differ and include various milk cessation methods, such as changes in milking frequency and in feeding,...

Antibiotic dry cow therapy (DCT) is an important part of most mastitis control programs. Updating DCT recommendations is an ongoing topic due to the global problem of antimicrobial resistance. Finland, along with other Nordic countries, has implemented selective DCT for decades. Our study analyzed Dairy Herd Improvement (DHI) information from 241 F...

The objectives of the present case-control study were to assess (1) daily activity patterns (lying time, number of steps, number of lying bouts, and lying bout duration), and (2) circulating concentrations of biomarkers of pain (substance P), inflammation (haptoglobin), and stress (cortisol) in lactating dairy cows diagnosed with clinical metritis....

The objective of this study was to survey drying-off practices and use of dry cow therapy (DCT) in Finland through an online questionnaire. The questionnaire was accessible to all dairy farmers of the Finnish dairy herd recording system in 2016 (approximately 5,400 farms). In total, 715 dairy producers across the country, representative of the Finn...

On-farm death (OFD) of a dairy cow is always a financial loss for a farmer, and potentially a welfare issue that has to be addressed within the dairy industry. The aim of this study was to explore the associations between OFD of dairy cows, housing, and herd management in freestall barns. To achieve the goal, we followed 10,837 cows calving in 2011...

Calving related losses due to dystocia and metritis affect the bottom line of dairy operations, and their underlying causes should be investigated to develop preventive procedures with consideration given to animal welfare and farm profitability. Monitoring cow activity patterns around the clock may allow dairy producers and their veterinarians to...

The cost of mastitis has been calculated at 6% of the value of production; at 2007 prices that is upwards of 2.1 billion dollars. It is estimated that 70-80% of this loss is due to subclinical intramammary infections (IMI) caused by organisms such as Staphylococcus aureus (SA). The control of SA is contingent on accurate diagnosis of IMI, yet curre...

Drying cows off at the end of lactation is a routine management practice in dairy operations. Most dairies in the United States and many other countries dry cows off abruptly (e.g., stop milking cows on a set day), which has been shown to affect cow comfort. Gradually reducing milk production is another approach to dry cows off, routinely used in s...

This retrospective study compared complication rates in 93 client-owned dogs (119 stifles) undergoing single-session bilateral, staged bilateral, or unilateral surgery for bilateral medial patellar luxation. Clinical characteristics and complication rates were compared and risk factors for major complications were explored. Sixty-five dogs had unil...

The objective of this study was to assess the effect of milk cessation method (abrupt or gradual) at dry off on milk yield and somatic cell score (SCS) up to 120 d in milk during the subsequent lactation. Data from 428 cows from 8 dairy herds in Ohio were analyzed. Abrupt cessation cows kept the farm's regular milking schedule (2 or 3 times) throug...

The objective of this study was to evaluate the effect of milking cessation method (abrupt or gradual) and daily milk yield before dry-off on milk leakage following dry-off and intramammary infections (IMI) at calving. Data from 1,086 quarters of 285 cows from 5 Ohio dairy herds were analyzed. All cows that were due to be dried off within a week we...

Staphylococcus aureus is the most common contagious mastitis pathogen affecting cows worldwide. Practices to control this organism have been advocated for decades, and identification of risk factors in individual herds is crucial in prevention and control of Staph. aureus. The objectives of this paper were to estimate prevalence of Staph. aureus in...

The objective of the present study was to assess the effect of parturition on behavioral activity [steps, standing time, lying time, lying bouts (LB), and duration of LB] 4 d before calving using electronic data loggers. Animals (n = 132) from 3 herds were housed in similar freestall barns using a prepartum pen 21 d before the expected calving date...

Exenatide extended-release (ER) is a microencapsulated formulation of the GLP-1-receptor agonist exenatide. It has a protracted pharmacokinetic profile that allows a once-weekly injection with comparable efficacy to insulin with an improved safety profile in type-2 diabetic people. Here we studied the pharmacology of Exenatide-ER in six healthy cat...

The objective of this study was to assess the role of teat skin colonization in Staphylococcus aureus intramammary infections (IMI) by evaluating genetic relatedness of Staph. aureus isolates from milk and teat skin of dairy cows using pulsed-field gel electrophoresis and characterizing the isolates based on the carriage of virulence genes. Cows in...

Objective: To evaluate shedding patterns of Staphylococcus aureus, specifically the association between clonal relatedness and shedding patterns of S aureus for cows with naturally occurring S aureus intramammary infection. Design: Longitudinal field study. Sample: Milk samples from 22 lactating cows (29 mammary glands) of varied numbers of la...

Background: Ciclosporin (CSA) is approved for the treatment of canine atopic dermatitis. Ciclosporin is metabolized by liver cytochrome P450 enzymes, a process inhibited by ketoconazole (KTZ). Hypothesis/objectives: The aims of this study were to determine skin and blood CSA concentrations when CSA was administered alone at 5.0 (Treatment 1) or...

Health care metrics of morbidity and mortality as well as health care policies related to antimicrobial use and biosecurity and biocontainment provide a means to evaluate operations rearing preweaned dairy calves. In general, studies of the aforementioned health care parameters for calf ranches are rare, compared with those for US dairy operations....

Mycoplasma haemolamae from dam to cria, whether colostral transmission of M. haemolamae occurs and provide preliminary data on colostral M. haemolamae specific antibody from pregnant alpacas on a farm with known prevalence of infection. M. haemolamae specific PCR was performed on blood and colostrum from pregnant alpacas and their cria (n = 52 pair...

The objectives of this study were to assess the responses to treatments (clinical cure and cow survival 14 d posttherapy) of cows with clinical endometritis (CE) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or subcutaneous ceftiofur crystalline free acid (CCFA) and subsequent pregnancy per artificial inseminati...

The utilization of farming operations specializing in rearing dairy heifer calves has increased since the early 1990s. However, these operations have not been as well characterized as US dairy operations with respect to demographic and health-related measures, particularly during the preweaning period. The objective of this study was to characteriz...

The goal of the current prospective field study was to examine the shedding patterns of naturally occurring Staphylococcus aureus intramammary infections and the association of pulsed field gel electrophoresis pulsotype with shedding. Milk samples from 5 multiparous and 2 primiparous cows identified with S. aureus intramammary infections were colle...

Selective dry cow therapy (SDCT) has received increasing attention in recent years owing to global concerns over agricultural use of antimicrobial drugs and development of antimicrobial resistance. The objective of this study was to evaluate the effect of SDCT on milk yield and somatic cell count (SCC) in dairy herds in the USA. Cows in four Ohio d...

The Internet is an increasingly common way for consumers to purchase puppies. Yet very little information is available about the types of puppies sold via the Internet. In addition these sales are not subject to United States Depart of Agriculture (USDA) regulation. The objectives of the study were to describe puppies sold via the Internet, to asse...

Epithelial migration (EM) is a process that serves as a self-cleaning and repair mechanism for the ear canal and tympanic membrane (TM). Epithelial migration has been evaluated in humans and several other species, but not in dogs. The objective of this study was to determine the rate and pattern of EM on the TM in clinically normal laboratory dogs....

The purpose of this study was to assess the effectiveness of a team-based educational program designed to enhance the flow of applied, research-based, nutrition information to dairy veterinarians. A comprehensive dairy cattle nutrition curriculum was developed and participants from 11 veterinary practices located in 5 states (IN, NY, PA, NM, and OH...

An adequate and clean artificial insemination (AI) technique is recommended to improve reproductive outcomes in dairy cattle. The objective of this study was to evaluate the effectiveness of using protective plastic sheaths (PS) to minimize contamination of the AI catheter (AIC) on pregnancies per AI (PAI) in lactating dairy cattle. Lactating cows...

A reliable and specific test that discriminates between acute neutrophil activation and chronic inflammatory disease may be useful in clinical decision making in a variety of conditions encountered in veterinary medical practice. An ELISA specific for neutrophil-derived haptoglobin-matrix metalloproteinase 9 (Hp-MMP 9) complexes was used to determi...

The purpose of this study was to determine the occurrence and genotypic relatedness of Salmonella enterica isolates recovered from feed and fecal samples in commercial swine production units. Of 275 feed samples, Salmonella was detected in 10 feed samples that originated from 8 of 36 (22.2%) barns, with a prevalence of 3.6% (10/275 samples). In fec...

Currently no standard definitions for the diagnosis of Staphylococcus aureus intramammary infection (IMI) exist. As a result, criteria applied in research to diagnose S. aureus IMIs have varied making comparisons between published works difficult. The goal of the current study was to define the optimal inoculum volume used in the diagnosis of natur...

Comprehensive continuing veterinary medical education (CVME) programs are critical for veterinary practitioners to update their knowledge and improve their skills and services. CVME must offer an educational environment in which veterinarians can effectively rejuvenate their knowledge and skills and learn about new practices. The Ohio Dairy Health...

Clinical endometritis (CE) is a common uterine disorder in high producing dairy cows that negatively impacts reproductive performance, thus diminishing profitability and sustainability. Reducing pathogenic bacteria load and uterine inflammation while enhancing immune defense are the general principle for endometritis therapy. An in vitro study has...

Despite improvements in management, prevention, and treatment, mastitis accounts for 26% of morbidity on US dairies, making it the most prevalent and costly disease of dairy cattle. In total, it is estimated that 70-80% of this loss is due to subclinical intramammary infections (IMI) such as Staphylococcus aureus (SA). The most prevalent contagious...

An adequate and clean artificial insemination (AI) technique is recommended to maximize reproductive outcomes in dairy cattle. The objective of this study was to evaluate the effectiveness of using protective sheaths (PS; Continental Plastic Inc., Delavan, WI, USA) to minimize contamination of the AI catheter (AIC) on pregnancies per AI (P/AI) in l...

The dry period plays an important role in maintenance of udder health. Cows are most susceptible to intramammary infections (IMI) after dry-off and near parturition and drying-off procedures may affect the likelihood of IMI at calving. The objective of this study was to evaluate the association of milk yield and infection status at dry-off with the...

Continuing education programs (CEP) are critical for veterinary practitioners to update and improve their skills and services (Moore et al, 2004 JVME 31, 146; Di Croce et al, 2008 Reprod Fertil Dev 20:86). CEP must offer an educational environment where veterinarians can effectively rejuvenate their knowledge, skills, and learn about new practices....

Isolation of pathogens from duplicate or multiple milk samples is currently considered the gold standard in diagnosis of bovine intramammary infections (IMI). However, in large field studies and especially in normal dairy production conditions, collection of single samples is often the most practical option to determine the causal agents of mastiti...

Concentration of natural protective factors (NPFs) which have the ability to inhibit growth of mastitis-causing pathogens increase rapidly following the cessation of milking of dairy cows. One such NPF is lactoferrin, an iron-binding protein present in high concentrations in dry-cow secretions. Earlier studies have demonstrated that intermittent mi...

In vitro studies show that hsp70 promotes gene expression for multiple viral families, although there are few reports on the in vivo significance of virus-hsp70 interaction. Previously we showed that hsp70-dependent stimulation of Edmonston measles virus (Ed MeV) transcription caused an increased cytopathic effect and mortality in transgenic hsp70-...

To evaluate use of kinetic gait analysis for detection, quantification, and differentiation of hind limb lameness and spinal ataxia in horses. Prospective clinical study. 36 horses. Procedures-Kinetic gait analysis with a force plate was performed for 12 clinically normal horses, 12 horses with hind limb lameness, and 12 horses with spinal ataxia....

Although milk and dairy products are important components of a healthy diet, if consumed unpasteurized, they also can present a health hazard due to possible contamination with pathogenic bacteria. These bacteria can originate even from clinically healthy animals from which milk is derived or from environmental contamination occurring during collec...

Hormonal estrus synchronization followed by heat detection of recipient animals is a widely used technique in embryo transfer (ET) programs around the world. However, the successful outcomes of ET rely heavily on appropriate heat detection of recipient animals. Additionally, limited availability of personnel and time to detect heat makes ET impract...

Coagulase-negative staphylococci (CNS) have become the most frequently isolated organisms from bovine intramammary infections in recent years. While antimicrobial resistance (AR) is not considered a major problem among mastitis pathogens, concerns over emerging AR in general are increasing worldwide. Little information exists about the association...

Mastitis is the most common and costly disease in dairy herds around the world. Antibiotic treatment of all quarters of all cows at the end of lactation (dry cow therapy, DCT) is a common mastitis control procedure in US dairy herds to eliminate existing and to prevent new intramammary infections (IMI) during the dry period. However, due to growing...

To evaluate factors that predispose to tibial tuberosity (TT) fracture after tibial plateau leveling osteotomy (TPLO) in dogs. Retrospective study. Dogs (n=182) with cranial cruciate ligament (CCL) rupture undergoing 213 TPLO surgeries. Medical records and radiographs of 2 groups of dogs that had TPLO surgery (2000-2001, 2004-2005) were evaluated t...

Interest in selective dry cow therapy (SDCT) has been increasing owing to concerns over development of antimicrobial resistance. Implementation of SDCT, however, requires a quick and cost-effective on-farm method for identifying cows for treatment and cows that can be left without treatment. The objective of the present study was to evaluate the us...

A field study was conducted to assess the impact of a contract breeding program that was offered by a breeding co-operative and featured tail chalking and daily evaluation of cows for insemination by co-operative technicians; dairy employees no longer handled estrous detection and insemination activities. From early 2002 until mid-2004, herd-level...

To compare the iridocorneal angle (ICA) and angle opening distance (AOD) in dogs with cataractous and noncataractous lenses; evaluate cataractous eyes ultrasono-graphically for association of postoperative ocular hypertension (POH) with the ICA, AOD, and postoperative echogenic anterior chamber debris; and evaluate intraobserver reliability associa...

Acute bloat syndrome (ABS) is an emerging problem in dairy herds. Affected calves suffer from the sudden onset of bloat or abdominal distention and die, generally within 6 to 24 hours. Little is known about this frustrating disease. To identify factors associated with ABS, a survey was developed and sent to members of the American Association of Bo...

Snai2, encoded by the SNAI2 gene, has been shown to modulate epithelial-mesenchymal transformation (EMT), the conversion of sessile epithelial cells attached to adjacent cells and to the basement membrane into dissociated and motile fibroblastic cells. EMT occurs during development, wound healing, and carcinoma progression. Using Snai2-null mice (S...

The objective of this research was to determine the effect of stocking density and inclusion of subtherapeutic chlortetracycline in the diet on Salmonella fecal prevalence and antimicrobial resistance in growing swine. A 2 x 2 factorial design was employed on a privately owned commercial swine farm. Four finisher rooms were included in the study. T...

The effect of a contract breeding program offered by a breeding co-operative was assessed using parametric frailty models with event-time analysis technique in a field study of Ohio dairies. The program featured tail chalking and daily evaluation of cows for insemination by co-operative technicians; dairy employees no longer handled estrus detectio...

To characterize the process by which people who find lost pets search for the owners. Cross-sectional study. Sample Population-188 individuals who found a lost pet in Dayton, Ohio, between March 1 and June 30, 2006. Procedures-Potential participants were identified as a result of contact with a local animal agency or placement of an advertisement i...

To determine whether coagulase-positive staphylococcal isolates that are genotypically the same strain obtained from pustules and carriage sites of individual dogs with superficial bacterial folliculitis have the same antimicrobial susceptibility phenotype. 40 dogs with superficial bacterial folliculitis. Samples were obtained from 3 pustules and 3...

To characterize the process by which owners search for lost dogs and identify factors associated with time to recovery. Cross-sectional study. Owners of 187 dogs lost in Montgomery County, Ohio, between June 1 and September 30, 2005. A telephone survey was conducted. 132 of the 187 (71%) dogs were recovered; median time to recovery was 2 days (rang...

To characterize the process by which owners search for lost cats and identify factors associated with time to recovery. Cross-sectional study. Owners of 138 cats lost in Montgomery County, Ohio, between June 1 and September 30, 2005. A telephone survey was conducted. 73 of the 138 (53%) cats were recovered; median time to recovery was 5 days (range...

Disease surveillance in animals remains inadequate to detect outbreaks resulting from novel pathogens and potential bioweapons. Mostly relying on confirmed diagnoses, another shortcoming of these systems is their ability to detect outbreaks in a timely manner. We investigated the feasibility of using veterinary laboratory test orders in a prospecti...

An observational study was conducted in order to assess the impact of a contract breeding program on the reproductive performance in a selected group of Ohio dairies using event-time analysis. The contract breeding program was offered by a breeding co-operative and featured tail chalking and daily evaluation of cows for insemination by co-operative...

Chronic renal failure is complicated by secondary hyperparathyroidism, which traditionally has been controlled by dietary restriction of phosphorus and administration of phosphorus binders. Early treatment of patients with chronic renal failure with calcitriol may be indicated because once established, parathyroid gland hyperplasia does not readily...

To estimate the association between ceftiofur use and the isolation of Escherichia coli with reduced ceftriaxone susceptibility from fecal samples of dairy cow populations. 1,266 dairy cows on 18 farms in Ohio. Individual fecal samples from all cows in the study herds were tested for Escherichia coli with reduced ceftriaxone susceptibility. Herd an...

To determine whether staphylococcal isolates cultured from pustules and carriage sites in dogs with superficial bacterial folliculitis were genotypically the same strain by use of pulsed-field gel electrophoresis (PFGE). 40 dogs with superficial bacterial folliculitis. Samples were obtained from 3 pustules and 3 carriage sites (anus, axillary skin,...

The aims of this research were to determine the association between inclusion of subtherapeutic chlortetracycline in the diets of swine and the prevalence and antimicrobial resistance of Salmonella; define the association between inclusion of subtherapeutic chlortetracycline and antimicrobial resistance in the aerobic Gram-negative fecal flora of s...

To evaluate the association between subjective lameness grades and kinetic gait parameters and assess the variability in kinetic parameters in horses with experimentally induced forelimb lameness. 32 horses. Forelimb lameness was induced in each horse via injection of lipopolysaccharide into 1 metacarpophalangeal joint (40 experimental trials). Sub...

A spreadsheet-based model was developed to estimate the economic effect of varying reproductive performance in dairy herds. Scenarios were created to model an average cow with respect to production, herd lifetime, and reproductive events. Average milk yield per day of life as well as lifetime calf and replacement heifer production were examined. Ad...

The association between milk yield at dry-off and intramammary infections at calving was evaluated from 116 lactations in one herd. Duplicate quarter samples were collected within 3 d after calving to estimate prevalence of intramammary infection at calving; information on cows' parity, daily milk yields, weekly somatic cell counts, and dry-off and...

Increasing antimicrobial resistance has become a serious concern worldwide and antimicrobial use in animal agriculture is currently under scrutiny. Mastitis is the most common reason for antibiotic use in dairy herds and thus, antimicrobial resistance of mastitis pathogens has received recent attention. The purpose of this study was to describe and...

Antibiotics that are excreted into the intestinal tract promote antibiotic resistance by exerting selective pressure on the gut microbiota. Using a beagle dog model, we show that an orally administered targeted recombinant beta-lactamase enzyme eliminates the portion of parenteral ampicillin that is excreted into the small intestine, preventing amp...

We modified an existing dairy management decision model by including economically important dairy cattle diseases, and illustrated how their inclusion changed culling recommendations. Nine common diseases having treatment and veterinary costs, and affecting milk yield, fertility and survival, were considered important in the culling decision proces...

The purpose of this study was to estimate the amount of variation in milk urea nitrogen (MUN) concentrations attributable to test-day, individual cow, and herd effects and to describe factors associated with MUN measurements in Ohio dairy herds. The data came from 24 Holstein herds, half of which were classified as low producing (LP) [rolling herd...

The objective of this study was to evaluate trends in reproductive performance in Ohio dairy herds during the 1990s. Stringent criteria for herd inclusion were applied to DHI records to ensure high quality and reliability of the data. The final data set contained 44,425 monthly herd summary records from 1772 herds from years 1992, 1994, 1996 and 19...

Equine protozoal myeloencephalitis (EPM) is a disease of horses that is primarily associated with infection with the apicomplexan Sarcocystis neurona. Infection with this parasite alone is not sufficient to induce the disease, and the mechanism of neuropathogenesis associated with EPM has not been reported. Nitric oxide (NO) functions as a neurotra...

Our purpose was to compare culling recommendations obtained from an economic-optimization model with actual culling of Finnish Ayrshire cows. The dynamic-programming (DP) model we used optimizes replacement and breeding decisions to maximize the net revenues from cows currently in a herd and their potential replacements over a 5-year decision horiz...

The purpose of this study was to evaluate the association between milk urea nitrogen (MUN) and fertility of dairy cows using field data. The data came from 24 dairy herds belonging to Ohio Dairy Herd Improvement Cooperative Inc. Reproductive data and MUN measurements from cows that calved between June 1998 and May 1999 and that had been bred at lea...

The objectives of this presentation are to review results of our previous and on-going research with respect to the risk factors and consequences of poor reproductive performance in dairy cows, and to develop an economic framework to optimize decisions related to dairy cow reproductive performance. To make profitable breeding and replacement decisi...

Rajala-Schultz PJ, Gröhn YT, Allore HG: Optimizing breeding decisions for Finnish dairy herds. Acta vet. scand. 2000, 41, 199–212. – The purpose of this study was to determine the effect of reproductive performance on profitability and optimal breeding decisions for Finnish dairy herds. We used a dynamic programming model to optimize dairy cow inse...

Rajala-Schultz PJ, Gröhn YT, Allore HG: Optimizing replacement Decisions for Finnish Dairy Herds. Acta vet. scand. 2000, 41, 185–198. – The purposes of the study were to determine how “an optimal herd” would be structured with respect to its calving pattern, average herdlife and calving interval, and to evaluate how sensitive the optimal solution w...

The purpose of this study was to determine the effect of reproductive performance on profitability and optimal breeding decisions for Finnish dairy herds. We used a dynamic programming model to optimize dairy cow insemination and replacement decisions. This optimization model maximizes the expected net revenues from a given cow and her replacements...

The purposes of the study were to determine how "an optimal herd" would be structured with respect to its calving pattern, average herdlife and calving interval, and to evaluate how sensitive the optimal solution was to changes in input prices, which reflected the situation in Finland in 1998. The study used Finnish input values in an optimization...

The effects of 15 diseases and reproductive performance on culling were studied in 39727 Finnish Ayrshire cows that calved in 1993 and were followed until culling or next calving. Survival analysis, using the Cox proportional hazards model, was performed with diseases and pregnancy status as time-dependent covariates. Parity, calving season and her...

The effects of 15 diseases, pregnancy status and milk yield on culling were studied in 39727 Finnish Ayrshire cows that calved in 1993 and were followed until culling or next calving. Survival analysis, using the Cox proportional hazards model, was performed with diseases, pregnancy status and milk yield as time-dependent covariates. Effects of par...

The effects of 15 diseases on time until culling were studied in 39,727 Finnish Ayrshire cows that calved during 1993 and were followed until the next calving or culling. The diseases studied were: dystocia, milk fever, retained placenta, displacement of the abomasum, metritis, non-parturient paresis, ketosis, rumen disorders, acute mastitis, hypom...

The effect of clinical mastitis on milk yield was studied in 24,276 Finnish Ayrshire cows that calved in 1993 and were followed for one lactation (i.e., until culling or the next calving). Cows that had only mastitis, but no other diseases, and cows that had no diseases (healthy cows) during the lactation were included in the study. Monthly test da...

The effects of milk fever, ketosis, and lameness were studied using data from 23,416 Finnish Ayrshire cows that calved in 1993 and were followed for one lactation (i.e., until culling or the next calving). Monthly test day milk yields were treated as repeated measurements within a cow in a mixed model analysis. Disease index variables were created...