Serum steroid and thyroid hormone concentrations in healthy domestic male and female alpacas.

Alpacas are high quality fiber producing animals, kept for production purpose and as pets. Endocrine imbalances from adrenal glands, gonads, or thyroid gland may result in coat abnormalities in domestic animals and affect reproduction. Contrary to many domesticated animals, information on hormone concentrations in alpacas is scarce. The purpose of this study was to provide steroid and thyroid hormone values in domestic alpacas. Blood was collected from healthy male (35 intact, 2 castrated) and female (48 non-pregnant, 3 pregnant) alpacas from local farms in Tennessee. Adrenal, reproductive, and thyroid hormones were analyzed. There were no significant differences in median concentrations of progesterone, estradiol, thyroxine (T4), and triiodothyronine (T3) between intact male and female non-pregnant alpacas. Median concentrations of testosterone, androstenedione, 17-hydroxyprogesterone, and cortisol were significantly higher in intact male alpacas compared to female non-pregnant alpacas. This information provides adrenal, gonadal, and thyroid hormone concentrations in alpacas to help with diagnosis of endocrine disorders.

Copper oxide wire particles effective against gastrointestinal nematodes in adult alpacas during a randomized clinical trial.

OBJECTIVE: To determine whether copper oxide wire particles (COWP) administered as an oral bolus effectively decrease fecal gastrointestinal nematode (GIN) egg counts in adult alpacas. ANIMALS: 57 adult alpacas. PROCEDURES: A double-blind clinical trial was performed during the months of April through August 2019. Adult alpacas enrolled in the trial were administered 2 g of COWP or a placebo control capsule PO on day 0 and day 45. On day 0 and at 15-day intervals, fecal samples were collected, and Modified McMaster fecal egg counts (FEC) were performed as well as physical examinations, including FAMACHA scoring and body condition scoring (BCS). Hematocrits were measured in 30-day intervals (days 0, 30, 60, and 90). Results were compared across groups. RESULTS: A significant decrease in mean FEC was observed in the COWP-treated group over time, compared with the placebo group. Mean BCS, FAMACHA score, and Hct did not differ significantly between groups. No clinical evidence of copper toxicosis was observed. CLINICAL RELEVANCE: Oral administration of COWP was determined to be a safe and effective method of reducing GIN FEC in adult alpacas.

Control of Salmonella Dublin in a bovine dairy herd.

Salmonella enterica serovar Dublin (S. Dublin) was diagnosed in a dairy herd after signs of acute gastroenteritis and sepsis. Two hundred eighty-three Holstein cattle were sampled resulting in 700 observations, and serology for S. Dublin was performed. Holstein cattle sampled were divided by origin and arrival date to determine on-farm exposure. Prevalence estimates were calculated and compared with control measures implemented on the dairy during the outbreak. One group of cows, presumed to be the original carrier animals, had the highest overall seroprevalence (76.5%). Seroprevalence decreased throughout the study, coinciding with testing and management changes. This report documents biosecurity measures that identified S. Dublin after the purchase of subclinical carrier cattle and the steps taken to successfully control herd transmission.

Alterations in pregnancy-associated glycoprotein concentrations of pregnant sheep experimentally infected with bovine viral diarrhea virus.

OBJECTIVE: To compare pregnancy-associated glycoprotein 1 (PAG1) concentrations in maternal (jugular vein) and fetal (uterine vein) circulations and amniotic fluid samples between pregnant ewes that were and were not experimentally infected with bovine viral diarrhea virus (BVDV). ANIMALS: 11 healthy pregnant yearling ewes. PROCEDURES: Before study initiation, all ewes were naïve to BVDV and confirmed pregnant by transabdominal ultrasonography at approximately 60 days of gestation. At 65 days of gestation, ewes were intranasally inoculated with a noncytopathic BVDV type 1b strain (concentration, 107 TCID50/mL; 2 mL/nostril; n = 6) or an equal volume of BVDV-free viral culture medium (control; 5). A blood sample was collected for measurement of PAG1 concentration before inoculation. At 80 days of gestation, each ewe was anesthetized and underwent an ovariohysterectomy. While sheep were anesthetized, blood samples from the jugular and uterine veins and an amniotic fluid sample were collected for measurement of PAG1 concentration. Fetal tissues underwent real-time PCR analysis for BVDV RNA, and placental specimens underwent histologic evaluation and immunohistochemical staining for BVDV antigen. RESULTS: At 80 days of gestation, BVDV RNA in fetal tissues and mild placentitis were detected in 5 of 6 BVDV-inoculated ewes. Mean PAG1 concentrations in the maternal and fetal circulations of BVDV-inoculated ewes were significantly less than those in control ewes. Mean amniotic fluid PAG1 concentration did not differ significantly between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE: Concentration of PAG1 in the maternal circulation may be a useful biomarker for determining placental health in sheep after viral infection of the reproductive tract.

Evaluation of the pharmacokinetics and efficacy of transdermal flunixin for pain mitigation following castration in goats.

The mitigation of pain associated with common management procedures is a rising concern among veterinarians, producers and consumers. Nonsteroidal anti-inflammatory drugs are vital compounds for this purpose due to their cost, convenience, and efficacy. A transdermal formulation of flunixin meglumine (FM) was approved for the treatment of pain in cattle; however, the efficacy has yet to be determined for small ruminants. The current study had two aims: 1) to determine the pharmacokinetics of transdermal flunixin meglumine (TD FM) in bucklings and 2) to evaluate pain mitigation by TD FM following castration. To evaluate pharmacokinetics, 12 male goats (mean age = 6 mo) received 2.2 mg/kg of FM IV (n = 6) or 3.3 mg/kg TD FM (n = 6). Plasma FM concentrations were measured. The mean C max, T max, and harmonic mean half-life for TD FM were 1.09 ± 0.65 µg/mL, 5.50 ± 2.95 h, and 7.16 ± 2.06 h, respectively. To evaluate the efficacy of pain mitigation, 18 goats were randomly assigned to three treatment groups: 1) TD FM and castration (FM CAST) (n = 6); 2) transdermal placebo and castration (PL CAST) (n = 6); and 3) TD FM and sham castration (SHAM) (n = 6). Plasma samples were collected at 0, 12, 24, 36, 48, 72, and 96 h to assess cortisol and prostaglandin E2 (PGE2). Daily dry matter intake (DMI) was recorded and body weight was measured at the beginning and end of the study. Thermography (IRT) images of the scrotum, as well as heart rate (HR), respiratory rate (RR), and rectal temperature, were taken twice daily. Separate mixed analysis of variance models were used to test the effects of treatment, time, and their interaction on mean body temperature, IRT, HR, and RR. Autoregressive covariance structure was utilized to account for repeated measures and individual goat DMI prior to the study was added as a covariate. There were no differences in vital parameters, IRT measurements, cortisol, or PGE2 in animals receiving either TD FM or placebo following castration (P > 0.05). DMI had a treatment by hour interaction and was significantly higher in FM CAST and SHAM groups than the PL CAST group (P = 0.04). Goats in the SHAM group gained weight throughout the study, whereas goats in all other groups lost weight (P = 0.02). Results indicate that TD FM may mitigate pain as demonstrated by increased DMI; however, a single dose may not be sufficient to reduce physiological indicators of pain associated with castration in goats.

Evaluation of intramuscular injection of oxytetracycline for use as an experimental model to induce pain and assess the efficacy of pain mitigation strategies in dairy cows.

OBJECTIVE: To evaluate IM injection of oxytetracycline as an experimental model to induce pain and assess the analgesic efficacy of flunixin meglumine (FM) in dairy cows. ANIMALS: 15 healthy nonlactating Jersey (n = 10) and Holstein (5) cows. PROCEDURES: In the first of 2 experiments, 5 Jerseys were administered oxytetracycline (10 mg/kg, IM), divided between the right side of the neck and left hind limb. The left side of the neck and right hind limb received sham injections. Cows were also randomly assigned to receive FM (2.2 mg/kg, IV; n = 3) or an equal volume of saline (0.9% NaCl) solution (0.044 mL/kg, IV; control; 2) once daily for 5 days. The mechanical nociceptive threshold (MNT) was measured before oxytetracycline administration and at predetermined times after each injection of the assigned treatment. Experiment 2 was similar to experiment 1 except it involved 5 Jerseys and 5 Holsteins, oxytetracycline was injected only in a hind limb, and the assigned treatment was administered for 10 days. RESULTS: For both experiments, mean MNT for the oxytetracycline injection site was consistently less than that for the sham injection site in the hind limbs, and mean MNT at the hind limb oxytetracycline injection site for FM-treated cows was greater than that for control cows beginning on day 3. CONCLUSIONS AND CLINICAL RELEVANCE: IM injection of oxytetracycline in a hind limb reliably induced signs of pain in dairy cows and, with validation, might be useful as an experimental model for assessing pain mitigation strategies in cattle.

Spontaneous Appearance and Transmission of Polydactyly in Dexter Cattle.

A 3-yr-old Dexter cow and her yearling Dexter heifer calf exhibited polydactyly. Neither animal was linebred within 5 generations. This cow-calf pair represented the first reported occurrence of polydactyly in Dexter cattle in the US or abroad. Based upon external examination, the cow was classified as having a spontaneous unilateral case of polydactyly with an extra digit along the medial digit of the right front limb and the heifer was classified as having bilateral polydactyly because both front limbs exhibited an extra digit along the medial digit. Radiographic examination confirmed bilateral status of the heifer and revealed bilateral status of the cow. The front feet of the cow and heifer had extra bone formation consistent with an extra digit along the medial digit. Neither animal suffered from limited mobility to date or required hoof treatments. The cow produced a second calf from a different sire, a bull calf that did not appear polydactylous per external examination and was not examined radiographically. The two polydactylous animals will remain in the breeding herd to produce more study calves unless their fitness becomes compromised. Genetic aspects of the cases are discussed.

Sodium balance and the dysnatremias.

The dysnatremias are defined as abnormalities in serum sodium concentration. Depending on the magnitude and duration of the sodium abnormality and the nature of any concurrent or primary disease, hypernatremia and hypernatremia may result in no consequences, subclinical impairment of health and productivity, or severe clinical disease. Dysnatremias can be the sequelae to diseases or environmental conditions that promote fluid gain or loss from the body, as well as medical interventions that add excessive amounts of sodium or water to the extracellular fluid. Extreme, sustained dysnatremia may result in central nervous system dysfunction and death.

Evaluation of sample handling effects on serum vitamin e and cholesterol concentrations in alpacas.

Clinical cases of vitamin E deficiencies have been diagnosed in camelids and may indicate that these species are more sensitive to inadequate vitamin E in hay-based diets compared to other ruminant and equine species. In bovine, cholesterol has been reported to affect vitamin E concentrations. In order to evaluate vitamin E deficiencies in camelids, the effects of collection and storage of the blood samples prior to processing were necessary. Reports vary as to factors affecting vitamin E and cholesterol in blood samples, and diagnostic laboratories vary in instructions regarding sample handling. Blood was collected from healthy alpacas and processed under conditions including exposure to fluorescent light, serum and red blood cell contact, tube stopper contact, temperature, and hemolysis. Serum vitamin E and cholesterol concentrations were then measured. Statistical analyses found that the vitamin E concentrations decreased with prolonged contact with the tube stopper and with increasing hemolysis. Vitamin E concentration variations were seen with other factors but were not significant. Time prior to serum separation and individual animal variation was found to alter cholesterol concentrations within the sample, yet this finding was clinically unremarkable. No correlation was seen between vitamin E and cholesterol concentration, possibly due to lack of variation of cholesterol.