Direct and Indirect Factors Influencing Cat Outcomes at an Animal Shelter.

Animal shelters play a vital role for pets, such as transitioning animals between homes, from outdoor communities into homes, caring for unadoptable and community animals, and providing a breadth of veterinary and welfare services. The goal of shelters is to move cats to their appropriate outcome as quickly as possible, which for many animals, is to rehome them as quickly as possible through adoption. Therefore, the ability to identify pre-existing factors, particularly those occurring outside the walls of the shelter, which result in specific outcomes is vital. In this study, we used structural equation modeling to test four hypotheses addressing how to predict cat outcome from a shelter in Washington, D.C. We developed four hypotheses that described how cat outcomes could be predicted, based on four general factors: (1) The characteristics of the cats; (2) The location of origin; (3) The type and date of intake; (4) The length of stay. Using 4 years of data from the Humane Rescue Alliance in Washington, D.C., we found support for each of our hypotheses. Additionally, we tested and found support for a global model, which comprised an amalgamation of our all our predictors. From the global model, we can conclude that many factors are at play in predicting cat outcomes in this shelter and very likely in many others as well. Critically, these factors are interconnected, indicating, for example, that cat characteristics mediate the influence of intake location on outcome type. Furthermore, our study highlights the importance of incorporating influences beyond the shelter when attempting to understand cat outcomes. Therefore, to modify cat outcomes most efficiently, such as increasing adoption probabilities, our results show that efforts may be most effective when incorporating multiple factors.

Choice of attractive conditions by beef cattle in a Y-maze just after release from restraint.

To provide useful information on how to moderate posthandling stress, the attractiveness of different conditions to beef cattle just after release from restraint was determined. Angus heifers were individually allowed to enter a choice area after 2 min of restraint in a squeeze chute and to choose between 2 pens. After the heifer had chosen a pen, it could freely access both test pens and the choice area for a further 5 min. In Exp. 1, each heifer was given 1 of the following choices: a pen with 3 familiar heifers (PEERS) vs. a pen with a pile of hay on a metal rack (FOOD; n = 34); PEERS vs. the bare pen (BARE; n = 34); and FOOD vs. BARE (n = 35). When the choice combination was PEERS vs. BARE, more heifers chose PEERS (P < 0.05). When the choice combination was PEERS vs. FOOD, more heifers than expected tended to choose PEERS (P < 0.10), whereas FOOD and BARE did not differ. The latency to choose either pen was shorter if PEERS was 1 of the 2 choices (P < 0.01). After choosing, more heifers entered the PEERS pen than the FOOD (P < 0.05) or BARE (P < 0.01) pens. In Exp. 2, another 86 heifers were given 1 of the following choices: a pen with a familiar handler standing inside (STI) vs. a pen with a novel object (NO; n = 29); a pen with the handler standing outside the pen (STO) vs. NO (n = 29); a pen in which the handler was sitting inside (SI) vs. NO (n = 28). Fewer heifers chose the pen with the human (STI, STO, and SI; all P < 0.01). Except for the choice of STO vs. NO, the number of heifers that had voluntarily chosen either pen was larger than expected (STI and SI; both P < 0.01). The number of times in which the NO pen was entered was greater than the STI and STO (P < 0.01), although the number of times in which the SI and NO pens were entered was not different. More heifers avoided the human, particularly a standing human. In conclusion, just after handling with restraint, returning cattle to the group of peers and not approaching the cattle needlessly should moderate their stress.

Ram lambs need FSH for normal testicular growth, Sertoli cell numbers and onset of spermatogenesis.

The effect of FSH on the development of the testis in the ram lamb was examined in two experiments where lambs were passively immunized against ovine beta-FSH from birth until 100 or 160 d. In both experiments, immunization resulted in a slower testicular growth relative to that of controls. This effect became apparent at around the start of the period of rapid testicular growth (60-70 d of age) and resulted in testicular weights at the end of treatment ranging from 37 to 51% of those of control groups. Within the testis, this was reflected in shorter seminiferous tubules (48-64% of controls) and in lower numbers of Sertoli cells per testis (57-82%). In the rams immunized until 160 d of age, spermatogenesis had begun and immunization against FSH provoked a lower production of germinal cells which was not solely due to the lower number of Sertoli cells but also due to fewer germinal cells being supported by each Sertoli cell. However, the numbers of A0 spermatogonia per testis and the daily production of the A1 spermatogonia were unaffected by immunization, but the production of the B2 spermatogonia and, as a consequence, of leptotene and pachytene spermatocytes and of round spermatids were all markedly lower (43-47% of controls). These effects were not due to any decreases in the secretion of LH or testosterone as seen in the blood levels of these two hormones. These results show that, in the ram lamb, FSH is essential for normal testicular development and for the establishment of a normal population of Sertoli cells. They also confirm that, once spermatogenesis is established, FSH is necessary for a normal production of germinal cells, with one or more of the divisions between the A1 and B2 spermatogonia being sensitive to suppression of FSH.

The arena test and cortisol response of sheep as indirect selection criteria for the improvement of lamb survival.

As part of a study of possible indirect selection criteria for the genetic improvement of lamb survival in the Australian Merino, two experiments were conducted. These experiments involved ewes from two flocks, one selected for superior lamb survival (Fertility Flock) the other an unselected flock (Random Flock). In the first experiment, the behaviour in an arena test of ewes from the two flocks was measured under two conditions; the ewes were tested either singly or in a group of four and the ewes were tested when in oestrus or not. When the ewes were tested singly, differences were detected between the two flocks in the total distance travelled, the minimum distance from a human operator in the arena and in the number of bleats. When the ewes were tested in a group of four, the differences in distance travelled and number of bleats disappeared; the difference in closest approach was maintained but the order of the two flocks was reversed; a difference appeared in the furthest distance from the operator. The experiment also showed that arena behaviour was not affected by the oestrous state of the ewes. In the second experiment, the cortisol response of the adrenal gland to stimulation by ACTH or by an external influence (barking dog) was examined in ewes from the two flocks. There were no differences between the two flocks in cortisol response to any of the stimuli. The results show that the behaviour of sheep in the two types of test is different, that the single-animal test may be the more appropriate when improvement in lamb survival is the objective and that the response of the adrenal gland shows little promise as an indirect criterion for selection.

The estrous cycle and induction of estrus in the australian feral sow (Sus scrofa).

In the first of 2 experiments, the estrous cycles of 11 Australian feral sows were studied. In 9 of the 11 sows the cycle was characterized by cyclic occurrences of low (0 to 2 ng/ml) and high (24.2 to 47.2 ng/ml) levels of progesterone. The low levels were associated, in all sows but one, with the standing response, lasting from 1 to 4 days, to a feral boar. Concomitant cyclic changes in vulval swelling and consistency of the vaginal mucus were also observed. Using intervals between the standing estrous response or the marked changes in the secretion of progesterone, the mean length of the cycle was calculated as 19.8 and 20.0 d, respectively. Two of the sows did not exhibit cyclic changes in any of the parameters measured, and on no occasion did either stand for service. In the second experiment, it was shown that estrus can be reliably induced in feral sows by either 1 of 2 methods: first, sows were induced to abort by prostaglandin injection. They were then administered gonadotrophin 48 to 72 h post abortion, and came into estrus 4 to 5 days later. Second, estrus was suppressed by feeding sows altrenogest, and was induced again about 9 days following altrenogest withdrawal.

The relationship between ram breeding capacity and flock fertility.

The effect of breeding capacity of rams on flock fertility was studied by exposing each of 15 rams to 1 of 15 flocks of 200 naturally-cycling ewes for 17 days. Five of the rams were arbitrarily designated as being of high breeding capacity (mean+/-SEM = 14.7+/-0.5 services in 2 3-hour pen breeding tests); five rams were designated as being of medium capacity (7.3 +/- 0.2); and the remaining five were designated as being of low breeding capacity (1.7 +/- 0.5). Breeding capacity was shown to be positively correlated with the number of services during flock mating, to the number of ewes mated and to insemination success. Breeding capacity as measured in a pen test of shorter duration (1 hour) was shown to be similarly related to flock fertility. Further, the number of services during flock mating was also positively correlated with the number of ewes mated and impregnated, as well as to the number of fetuses conceived and to insemination success. Breeding frequency of the ram is, therefore, closely related to flock fertility, but breeding capacity, as measured in the present study, is only a moderately accurate indicator of breeding frequency.

Endocrine control of mammalian testicular ontogenesis.

The endocrine control of ontogenesis of the male gonad involves the development of the gonad itself and, at the same time, the development of the endocrine system. During the impubertal phase, the seminiferous tubules contain supporting cell and gonocytes, both of which increase in number by mitotic divisions. Over this period, the pituitary secretion of both FSH and LH increases, FSH progressively and LH in pulsatile fashion. In the interstitial tissue, the numbers of Leydig cells also increase. The increase in LH secretion and in leydig cell numbers leads to an increase in testosterone secretion, so that a little before puberty the system of LH-testosterone feedback is fully operational. The testicle then reaches the prepubertal phase, where the supporting cells stop dividing and differentiate to become the highly specialised Sertoli cells. Thereafter, their numbers remain almost constant. the gonocytes now begin rapidly dividing and differentiating, their rate of division resulting in a drastic increase in testicular size. The end result of their division and differentiation is that the testicle begins to produce spermatozoa. Very few are produced at first, but eventually production reaches adult levels and the testis begins to show normal spermatogenic cycle. Also during this phase, the pulsatile secretion of LH and testosterone continue and the secretion of FSH increases. The developments of these two systems are not unrelated. The division of the supporting cells and their maturation into Sertoli cells are under the control of LH in synergy with FSH, while the differentiation of primordial cells into spermatogonia and the subsequent production of spermatozoa are under the control of FSH, LH and testosterone.