Assessment of welfare and brachycephalic obstructive airway syndrome signs in young, breeding age French Bulldogs and Pugs, using owner questionnaire, physical examination and walk tests

Brachycephalic obstructive airway syndrome (BOAS) is a major welfare problem in short-nosed breeds, such as the French Bulldog and Pug. In addition to respiratory difficulties, exercise intolerance and impaired recovery are major signs of BOAS. To select healthier breeding animals, exercise tolerance tests, such as the 1,000-m walk test, are already used in several countries for brachycephalic dogs, although evidence supporting their use is still scarce. The aims of this study were to assess the daily welfare of young, breeding-age French Bulldogs (n = 44) and Pugs (n = 51) using an owner questionnaire, and to evaluate 6-min walk test (6MWT) and 1,000-m walk test usability for differentiation between non- or mildly BOAS-affected dogs and more severely affected dogs. Only four out of 95 French Bulldog and Pug owners reported that the BOAS signs limited the daily activities of their dogs. However, according to the physical, examination-based veterinary BOAS grading, 31/95 of the dogs had moderate to severe BOAS signs. In both breeds, the more severely affected dogs performed both exercise tests more poorly than those with no or mild BOAS signs. The longer exercise, namely the 1,000-m test, seemed slightly better able at differentiating between affected dogs and less affected ones. The results of this study further support the use of exercise tests as an important part of the breeding selection in French Bulldogs and Pugs. By influencing the breed standards set by Kennel Clubs and by using breeding selection tools, the harmful impacts of brachycephaly can be diminished.

Flood Tides Affect Breeding Ecology of Two Sympatric Sharp-Tailed Sparrows

Breeding synchrony with the lunar cycle has been reported for many marine organisms but is essentially unknown for birds. Most organisms shown to breed synchronously with the lunar cycle provide no parental care to young, and such explosive breeding assemblages are usually promiscuous. Saltmarsh Sharp-tailed Sparrows (Ammodramus caudacutus caudacutus) nest exclusively on salt marshes and are subjected to predictable, catastrophic flooding caused during flood tides every 28 days. Here, we show that Saltmarsh Sharp-tailed Sparrow males were nonterritorial and promiscuous and provided no parental care to young. Breeding behaviors of both sexes were synchronized with the lunar cycle. By contrast, males of a sympatric sister species, Nelson's Sharp-tailed Sparrow (A. nelsoni subvirgatus), consistently mate-guarded females, and breeding was not synchronized with the lunar cycle, yielding 21% lower reproductive success compared with Saltmarsh Sharp-tailed Sparrows. Saltmarsh and Nelson's sharp-tailed sparrows renested 2.9 ± 0.6 (SE) days and 10.3 ± 1.7 days after nest flooding, respectively. Patterns of vicariance between Nelson's and Saltmarsh sharp-tailed sparrows may explain the differences in social behavior and nesting ecology. Ancestral sharp-tailed sparrows diverged from Seaside Sparrows (A. maritimus) in tidal wetlands, and Nelson's Sharp-tailed Sparrows then diverged from Saltmarsh Sharp-tailed Sparrows in nontidal freshwater wetlands of interior North America. Nelson's Sharp-tailed Sparrows' range recently expanded into coastal salt marshes, where Saltmarsh Sharp-tailed Sparrows are better adapted to tidally influenced inundations. Adaptation to tidal flooding partially explains the evolution of the unique Saltmarsh Sharp-tailed Sparrow mating system.Las Inundaciones Mareales Afectan la Ecología Reproductiva de Dos Especies Simpátricas de Ammodramus

COMPARISON OF THREE METHODS FOR ADJUSTING SCROTAL CIRCUMFERENCE IN CHAROLAIS, LIMOUSIN AND HUNGARIAN FLECKVIEH YOUNG BULLS UNDER FARM CONDITIONS

This study was conducted to compare three different methods for calculating scrotal circumference (ASC1, ASC2, ASC3) adjusted to 365 days of age in Charolais, Limousin and Hungarian Fleckvieh young bulls at the end of the self-performance test. Young breeding bulls from three Charolais, Limousin and Hungarian Fleckvieh breeding farms (farm A: n = 40; farm B: n = 9; farm C: n = 11) were used. The young bulls were kept in loose housing system, in small groups, and fed a diet based on maize silage and concentrate. The scrotal circumference of young bulls was measured at the widest part of the scrotum at the beginning and at the end of the test. Significant growth was observed (+13.6 cm; +8.9 cm; +10.5 cm, P < 0.001) in scrotal circumference (SC) for all breeds except the Hungarian Fleckvieh (ASC2-ASC3: 37.5 vs. 37.6 cm). All differences among the means of the measured and adjusted SCs were statistically confirmed at the P < 0.05 level of significance. A moderate to close positive correlation (r = 0.49-0.99) was calculated among the measured SC and the three types of ASC. The results suggest that method I (ASC1) and method II (ASC2) should be used by the breeders for adjusting scrotal circumferences in the practice.

Prediction of lean yield in yearling bulls using real-time ultrasound

A study was undertaken to determine the repeatability and accuracy of ultrasound measurements taken on yearling bulls and to assess the value of these live measurements to predict lean yield. Ultrasonic fat depth and 1. dorsi area were measured on 616 yearling bulls prior to slaughter. Corresponding carcass measurements were obtained through the Agriculture Canada Blue Tag Program. Carcass side lean (LEANYIELD) was extrapolated from the lean content of the seven-bone rib section from the carcasses of 41 Angus and 41 Charolais bulls. Stepwise multiple regression used live (USFAT and USREA) measurements to predict LEANYIELD. Repeatability (SER) and accuracy (SEP) statistics for USFAT were 0.8 mm and 1.6 mm, respectively. The corresponding results for USREA were SER = 4.3 cm2 and SEP = 7.8 cm2. The ultrasound lean yield (USLEAN) prediction equation was: USLEAN = 599.2 − (9.5 × USFAT) + (1.1 × USREA); R2 = 0.73, RSD = 17.9 g kg−1. Results indicated that LEANYIELD was predicted better by USLEAN (SEP = 18.0 g kg−1) than by BTLEAN (SEP = 22.6 g kg−1). Results from a second group of dissected bulls (n = 110) confirmed that ultrasound can predict LEANYIELD as effectively as carcass measurements (SEP = 22.8 and 22.6 g kg−1 for USLEAN AND BTLEAN) in young breeding bulls in this study. Key words: real-time ultrasound, performance testing, beef bulls, carcass traits

Performance of young breeding cattle in commercial herds in the south-west of Western Australia. 2. Liveweight, body condition, timing of conception and fertility in first-calf heifers

A 5-year study was conducted using 2531 first-calving heifers on commercial properties in the south-west of Western Australia. Breed types included Angus, Angus x Friesian, Angus x Hereford, Devon crossbred, Hereford x Friesian, Hereford, Simford, Beef Shorthorn crossbred, Wokalup multibreed and Simmental. Heifers first calving between 22 and 29 months of age were monitored from first until second calving, with the emphasis on liveweight and condition score measured during joining (range 9-21 weeks) and subsequent reproductive performance. The timing and level of reconception after first calving were tested for their relationship with liveweight, condition and their rates of change during joining. At second conception, mean liveweight varied widely both within and among breeds but apparently corresponded to maturity type. Liveweights (kg) of first-calvers were: Angus, 336; Hereford, 368; Angus x Friesian, 378; Simford, 423; Simmental, 467. At second conception, first-calvers were generally making moderate liveweight gains (0.2-0.6 kg/day) and most conceived at a condition score of 1.5-2.0. In 8 breeds with sufficient data for analysis, increased calving rates were related to heavier liveweight or better condition during joining, with the strongest relationships based on weight or condition at the beginning of joining. In general, fertility was adversely affected by liveweight <310 kg at the start of joining in early-maturing breeds such as Angus, Hereford and Beef Shorthorn crossbred and liveweight <345 kg in later maturing or larger breeds including Simford, Angus x Friesian crossbred and Wokalup multibreed. In addition, the fertility of the larger breeds was more influenced by liveweight, with greater partial regression coefficients, than was fertility in Angus or Herefords. First-calvers with condition scores less than an apparent threshold of 1.5, and those losing more than 0.6 kg/day, had lower calving rates than their counterparts in better condition or those losing less weight. In both early and later maturing breed types there was a linear relationship between higher calving rates and increasing liveweight gain. The average time of second conception for most breeds was within 5-6 weeks of the start of joining and most intercalving intervals were 370-390 days. Both time to conception and the intercalving interval were negatively and linearly related to liveweight (7-14 days reduction/100 kg), condition (7-13 days reductionlunit of condition), or weight change early in joining. Generally, heavier weights were required to effect the same reduction in time to conception in larger breeds such as Angus x Friesian, 314 Hereford x Simmental and Wokalup multibreed than in early-maturing breeds such as Angus or Hereford. Development of guidelines to producers based on second-conception weights, condition scores and the log-linear relationships derived for the breeds and crossbreeds in this work is discussed in the light of the poor reproductive performance sometimes found in this class of breeder.

The effect of differing patterns of energy intake in mid and late pregnancy in maiden heifers

The sharp fall in dairy cow numbers which has occurred since the introduction of milk quotas in 1983 has seen a resurgence of interest in the suckler cow. As a result the June 1989 census revealed that the number of heifers under two years old destined for breeding was 6.1 percent up on the previous year. It therefore seems clear that over the next few years as the beef herd expands more emphasis is going to be placed on the young breeding heifer. Problems with breeding from young heifers are well known. However, current knowledge of the effects of pre partum nutrition on heifer and calf performance is incomplete. The purpose of this study was therefore to monitor the effects, of differing patterns of energy intake in mid and late pregnancy in maiden heifers.

Reproduction in the Female Dasyurid Antechinus-Minimus-Maritimus (Marsupialia, Dasyuridae)

Reproduction in female Antechinus minimus maritimus was investigated in the field and laboratory. Field data were obtained from a mark-recapture study. A laboratory colony was maintained to investigate the oestrous pattern, length of gestation and development of pouch young. Breeding occurred in winter with births in July or August. Gestation (mean � SD) was 30.6 � l.5 days for animals mated in the laboratory. Epithelial cells were present in the urine for 34.8 � 8.3 days, a lengthy period compared to A. stuartii (19.3 � 4.4 days). Ovaries from females before the breeding season contained small developing follicles. During the breeding season Graafian follicles (4-8 per ovary) or corpora lutea (4-13 per ovary) were found. Reproduction in A. m. maritimus females is similar to that described previously in other Antechinus.