Technical note: Accelerometer-based recording of heavy breathing in lactating and dry cows as an automated measure of heat load.

Monitoring thermal status using a reliable, practical method is essential for proper cattle management during periods of high heat load. Our objective was to determine whether accelerometer-based tags, which measure heavy breathing and other behaviors on a minute-by-minute basis, accurately reflect thermal status. We hypothesized that the tags would mirror core body temperature as recorded by continuous intravaginal loggers, and that response to a cooling intervention would also be captured. Data were collected during a 3-d period from 10 late dry and 20 high-producing cows at peak lactation, each fitted with an intravaginal temperature logger and tag attached to a collar. The relationship between vaginal temperature and proportion of cows recorded as breathing heavily averaged over the three 24-h periods was described separately for each group, and during a 1-h block capturing 2 intensive cooling sessions in lactating cows. Finally, the log of the odds of a cow breathing heavily in each minute relative to vaginal temperature in cows before cooling was analyzed using a linear mixed model. The proportion of cows breathing heavily in a group mirrors changes in vaginal temperature in both dry and lactating cows. In contrast to the dry cows, lactating cows suffered from excessive heat load to a much greater degree. Cooling intensively with showers and fans effectively mitigates the effects of excessive heat load, as reflected by response in vaginal temperature and proportion of cows breathing heavily. The probability of heavy breathing increases by approximately 10% for each 0.5°C rise in vaginal temperature above 39.0°C. In conclusion, accelerometer-based technology that automatically records heavy breathing provides a practical means of continuously assessing heat load status of dairy cows, whether lactating or dry, and their response to cooling intervention. This has the potential to optimize both cow and resource management during periods of high heat load.

Technical note: Use of an automated grooming brush by heifers and potential for radiofrequency identification-based measurements of this behavior.

Healthy cattle readily use grooming brushes but this behavior subsides when animals become ill. Tracking use of a brush may provide an opportunity for health monitoring, especially if the process could be automated. We assessed how healthy heifers groom themselves on a brush and hypothesized that radiofrequency identification (RFID) could be used to accurately and automatically record this behavior. Angus and Hereford heifers (n = 16) were fitted with 2 ultra-high-frequency RFID ear tags and monitored in groups of 8 while housed in a pen with an electronic brush, video cameras, and 4 RFID antennas. Each heifer was observed for a 6-h period using continuous video recordings, and brush contact was characterized in terms of anatomic region involved (head/neck, trunk, or posterior) and when not touching the brush but within 1 body length of it. The RFID data were collected for the same period and then processed such that intervals of up to 16 s with no detections but contained between 2 recordings were also considered positive (animal in brush proximity). Brush proximity (RFID) was regressed against brush contact duration (video) and the sensitivity and specificity for each individual heifer calculated. Across heifers, the majority of brush use involved the head/neck, although a few heifers demonstrated relatively large amounts of posterior contact, which contributed to false-negative readings when antennas failed to read the ear tags. Furthermore, for the majority of time that animals were near the brush, they were not in contact with it but rather standing or lying nearby, resulting in false-positive readings. It follows that the ability of the RFID system to accurately detect brush contact varied widely across individual heifers (sensitivity 0.54-1.0; specificity 0.59-0.98), with RFID generally overestimating the duration of brush proximity relative to actual time spent in brush contact. The implication is that RFID-based ear tag recording of brush proximity relative to continuous video observations of contact does not yield accurate results in certain heifers and therefore, as currently configured, is not a reliable representation of this type of grooming behavior.

Clinical features of hypoadrenocorticism in soft-coated wheaten terrier dogs: 82 cases (1979-2013).

The objective of this retrospective case series, which included 82 client-owned soft-coated wheaten terriers, was to characterize clinical features of hypoadrenocorticism in this breed. Median age at diagnosis was 3.5 years. There was no gender predilection. Clinicopathologic findings included sodium/potassium ratio < 27 (85%), hyperkalemia (76%), hyponatremia (63%), elevated blood urea nitrogen (83%) or creatinine (71%), and hypercalcemia (36%). Nine dogs with normal sodium and potassium (11%) were older and less often azotemic, hyperphosphatemic, or hypercalcemic. Twenty-one dogs (26%) developed protein-losing nephropathy (n = 18) and/or end-stage renal disease (n = 3). Overall median survival time was 5.4 years, but was shorter in dogs with normal sodium and potassium at diagnosis (4.2 years), or those with subsequent protein-losing nephropathy (4.2 years). This population showed no gender predilection, unlike that reported in the general canine population with hypoadrenocorticism, and more comorbid protein-losing nephropathy than in the general soft-coated wheaten terrier population.

Caractéristiques cliniques de l'hypoadrénocorticisme chez les chiens Terrier irlandais à poil doux : 82 cas (1979­2013). L'objectif de cette série de cas rétrospectifs, qui incluait 82 Terriers irlandais à poil doux appartenant à des clients, consistait à déterminer les caractéristiques cliniques de l'hypoadrénocorticisme chez cette race. L'âge moyen du diagnostic était de 3,5 ans. Il n'y avait pas de prédilection selon le sexe. Les résultats clinicopathologiques incluaient le ratio sodium-potassium < 27 (85 %), l'hyperkaliémie (76 %), l'hyponatrémie (63 %), un taux élevé d'azote uréique du sang (83 %) ou de la créatinine (71 %) et l'hypercalcémie (36 %). Neuf chiens avec un taux de sodium et de potassium normal (11 %) étaient âgés et étaient moins souvent azotémiques, hyperphosphatémiques ou hypercalcémiques. Vingt-et-un chiens (26 %) ont développé la néphropathie avec perte de protéines (n = 18) et/ou la maladie rénale en phase terminale (n = 3). Le temps de survie global moyen était de 5,4 ans, mais il était écourté chez les chiens avec un taux normal de sodium et de potassium au moment du diagnostic (4,2 ans) ou chez ceux atteints subséquemment de néphropathie avec perte de protéines (4,2 ans). Cette population n'a pas présenté de prédilection selon le sexe, contrairement à ce qui avait été signalé dans l'ensemble de la population canine atteinte d'hypoadrénocorticisme, et elle affichait une hausse de néphropathie concomitante avec perte de protéines par rapport à la population générale des Terriers irlandais à poil doux.(Traduit par Isabelle Vallières).