Journal of Animal Science

Mengers, J. N.;Dennis, R. L.

doi: 10.2527/asasann.2017.001pmid: N/A

Abstract Poultry breeding flocks experience stress from numerous sources including feed restrictions, confinement, social aggression, changing environments, transport, and stockperson turnover. Maternal diet and stress can increase catecholamine levels, including norepinephrine (NEP), and alter tyrosine metabolism. Elevated NEP levels impact the embryo and lead to altered survival behaviors in the developed offspring. In order to determine the effects of NEP on feeding and social behaviors, activity level, and fear response, Japanese quail (Coturnix japonica) embryos were injected with 10 μL of 0.01 or 0.05 M of NEP or saline at ED1 (n = 130) and incubated with intact controls (n = 80). Weekly behavioral scan samples (AM and PM) were taken from wk 4 (juvenile) to 11 (sexually mature) with rehoming between wk 6 and 7 samplings. Body weights were taken every other week, and organ weights were taken at wk 11. Tonic immobility tests were conducted at 2, 5, and 9 wk. Results showed a greater incidence of eating behavior in birds that received 0.01 or 0.05 M of NEP compared with control birds, with eating frequency increasing over time in older NEP-treated birds (P = 0.019, wk 5; P = 0.005, wk 10; and P = 0.017, wk 11). Younger birds that received 0.01 M of NEP spent more time drinking compared with birds that received 0.05 M of NEP or controls (P = 0.013, wk 5, and P = 0.016, wk 6). Birds that received 0.05 M of NEP foraged more frequently compared with birds that received 0.01 M of NEP (P = 0.002, wk 6; P = 0.046, wk 8; P = 0.002, wk 10; and P = 0.009, wk 11). Following rehoming, NEP-treated birds exhibited an increase in inactivity compared with control birds (P = 0.007, wk 7). Birds that received 0.01 M of NEP weighed significantly less than birds that received saline (P = 0.008, wk 3; P = 0.010, wk 5; P = 0.006, wk 7; and P = 0.006, wk 9). Relative heart, liver, and spleen weights did not significantly differ (P = 0.412, P = 0.561, and P = 0.293, respectively). We observed no difference in tonic immobility inductions (P = 0.637, wk 2; P = 0.475, wk 5; and P = 0.349, wk 9) or duration (P = 0.108, wk 2; P = 0.426, wk 5; and P = 0.730, wk 9). Our data show that NEP injections during early embryonic development have lasting impacts on feeding and drinking behaviors, activity levels, and weight. These results suggest that maternal and environmental stress, including rehoming, impact both production and behavior with implications for poultry management. American Society of Animal Science

Na, S. W.;Kang, H. J.;Kim, Y.;Baik, M.

doi: 10.2527/asasann.2017.002pmid: N/A

Abstract In lower critical temperature, cattle increase their metabolic rate to supply more body heat. This increases nutrient requirements, particularly energy, and may affect rumen fermentation characteristics and thus the rumen microbial ecosystem. This study was performed to examine whether cold temperature and fat supplementation affects rumen microbial populations in Korean cattle. Six Korean cattle steers (average 17 mo of age and 375 kg of BW) were divided into a conventional control diet group (n = 3) and a 1.75% fat supplementation group (n = 3). Steers were allowed to receive daily a concentrate (1.5% of BW) and 3 kg of tall fescue hay. Steers were raised in metabolic cages in a temperature-controlled room with 2 different temperature conditions. Animals were grown in natural cold condition for 12 d with 2 different diets, and they were then grown in neutral normal temperature for 12 d. There was a 10-d resting period between the 2 temperature conditions in a feedlot with the control diet. The minimum ambient temperature (−6.24°C) of the cold environment was lower (P < 0.01) than that (15.8°C) of the normal temperature condition. Rumen fluid samples were obtained via stomach tube on the last day of each of 2 experimental periods 3 h after the morning feeding. Rumen fluids were frozen in liquid nitrogen and stored at −70°C. Genomic DNA was extracted and used for 16S rRNA metagenomics sequencing by an Illumina HiSeq 2000 system. Raw sequencing data was processed by QIIME. Statistical analysis was conducted by 2-way (diet and temperature) ANOVA. Bacteroidetes was the most abundant phylum followed by Firmicutes in all rumen fluid samples. Relative abundances of the genera Propionibacterium and Anaeroplasma were higher (P < 0.05) in cold temperature than in normal temperature, whereas those of Desulfovibrio and Mogibacterium were lower (P < 0.05) in cold temperature. Relative abundance of the family R4-45B was higher (P < 0.05) in the fat diet group than in control diet group, whereas that of Pyramidobacter was lower (P < 0.05) in fat diet group. Real-time PCR was performed to validate the metagenomics data and to identify the changes of microbial population at species levels with 19 microbial primers. Succinimonas amylolytica was higher (P < 0.05) in cold temperature than in normal temperature. Ruminococcus albus was higher (P < 0.05) in the fat diet group than in the control diet group. In conclusion, metagenomics and real-time PCR results reveals that cold temperature and fat supplement affect microbial populations in the rumen of beef cattle. American Society of Animal Science

Hoonhout, L.;Reimert, I.;Daigle, C. L.

doi: 10.2527/asasann.2017.003pmid: N/A

Abstract Social interactions within a group of cattle may provide information about an individual animal's health status. To determine whether social licking (e.g., allogrooming) can be used as an indicator of animal health, Bos indicus–cross steers (n = 36) were housed in drylots (8–10 steers/pen), individually identified, and video recorded prior to (d −2 and −1) and after (d 1, 2, 4, and 8) inoculation (d 0). Half of the cattle within each pen were inoculated with Mannheimia haemolytica (MH) and the other half were inoculated with a phosphate buffer solution (PBSo). We hypothesized that MH cattle would receive more allogrooming after inoculation. Cattle were fed 2 times per day, and video recordings on d −2 and 4 were decoded 2 h before and 2 h after each feeding for the duration of time (s) each steer gave or received allogrooming. The total amount of time on d −2 and 4 spent giving and receiving allogrooming was used to develop 4 behavioral phenotypes: 1) GIVE (n = 4; gave > 1 s and received 0), 2) RECEIVE (n = 8; gave 0 and received > 1), 3) BOTH (n = 23; gave > 1 and received > 1), and 4) NEUTRAL (n = 1; gave 0 and received 0). The GIVE steers (130.3 ± 104.3) spent less time (s) allogrooming than BOTH steers (149.4 ± 42.5). The RECEIVE steers (55.3 ± 18.0) spent less time (s) receiving allogrooming than BOTH steers (150.0 ± 26.9). A generalized linear mixed model (PROC MIXED) evaluated the impact of day and treatment on the duration of time spent giving or receiving allogrooming. Neither treatment nor day influenced the duration of time spent giving allogrooming. Treatment (P = 0.13) slightly influenced the duration of time spent receiving allogrooming. Mannheimia haemolytica steers (138.3 ± 32.3) spent more time (s) receiving allogrooming than PBSo steers (77.9 ± 21.3). Transition matrices identified that 27% of MH and 16.7% of PBSo steers that were classified as BOTH on d −2 remained BOTH on d 4. Steers classified as GIVE on d −2 were classified as RECEIVE on d 4 for 11.1% of PBSo steers and 0% of MH steers. Of the MH-inoculated steers classified as BOTH on d −2, 27.8% were reclassified as RECIEVE on d 4, whereas no PBSo steers made this transition. Allogrooming is a comfort behavior associated with social dominance and partnership, yet some steers were observed to never give or receive allogrooming. The duration of time individuals receive allogrooming may be a useful metric for identifying sick animals and warrants further investigation. American Society of Animal Science

Averós, X.;de Heredia, I. Beltrán;Ruiz, R.;Estevez, I.

doi: 10.2527/asasann.2017.004pmid: N/A

Abstract The impact of maternal separation on the capacity of lambs to respond to social challenges and stressful situations might be modulated by prenatal stressors such as environment conditions experienced by gestating females. In this study, we explored the impact of 2 experimental group sizes (GS) experienced by gestating ewes (prenatal stress) and of early maternal separation (postnatal stress) on the social motivation and fear responses in lambs. Fifty-four pregnant Latxa ewes (Basque Country, Spain) were randomly assigned to 2 experimental prenatal GS treatments of 6 or 12 ewes/pen; GS6 and GS12, respectively). After birth, lambs from each treatment were either left with mothers (MR) or early separated (ES) 24 h after birth. Thirty-two 2- to 8-d-old lambs of similar ages were split into groups of 3, coming from the same pre- and postnatal treatment. Each lamb was sequentially subjected to a novel arena test, a novel object test, and a social motivation test. Lamb behavior, movement patterns, and vocalizations were collected. The effects of pre- and postnatal treatments, their interaction, and male/female differences were determined using the GLIMMIX procedure in SAS. Pen during gestation nested within group size and individual ewe nested within pen during gestation and group size were included as random effects. No significant interactions were detected between pre- and postnatal treatments (P > 0.05). Latency to move during the social motivation test was shorter for MR lambs than for ES lambs (3.5 ± 1.6 vs. 7.3 ± 1.7 s for MR and ES lambs, respectively; P = 0.0327), which also had longer inactive periods (38.8 ± 3.6 vs. 15.0 ± 3.0%; P = 0.0278) and explored less (22.1 ± 3.4 vs. 40.9 ± 5.5%; P = 0.0332). The GS6 lambs remained closer to the other test lambs than did GS12 lambs in the social motivation tests (93.9 ± 1.1 vs. 90.08 ± 0.9% of total time; P = 0.0044). Females walked longer net distances than males in the novel arena tests (254.8 ± 7.6 vs. 221.9 ± 8.7 cm, respectively; P = 0.0257). Females also had shorter latencies to move (2.1 ± 1.6 vs. 8.7 ± 2.0 s; P = 0.0488) and walked longer net distances during the social motivation tests (249.6 ± 10.5 vs. 217.5 ± 9.8 cm, respectively; P = 0.0227). No evidences of impact on fear responses were obtained. These results appear to suggest that MR lambs and, to a lower extent, those born from ewes housed at GS6 during pregnancy had increased social motivation. Females appear to show a higher social motivation. American Society of Animal Science

Parham, J. T.;Tanner, A. E.;Eskridge, K. M.;Wahlberg, M. L.;Swecker, W. S.;Lewis, R. M.

doi: 10.2527/asasann.2017.006pmid: N/A

Abstract Excitable cattle can be detrimental to the health of workers and the cattle themselves, with negative effects on production traits. Acclimation to handling has been proposed to increase docility in excitable cattle as an alternative to culling. The objective of this study is to determine if frequent handling causes a change in docility. A factorial design of 2 groups, frequent (FR) and infrequent (IN), and 3 recording periods, each 1 mo apart, was used. Cattle in the FR group were observed 3 consecutive days within each recording period whereas cattle in the IN group were observed only once. Twenty Angus heifer calves were randomly assigned to each group, and the experiment was repeated over 3 yr. Observations taken on the calves included chute score (1 = docile and 6 = aggressive), exit score (1 = docile and 5 = aggressive), and exit velocity (s). Data were analyzed using ANOVA, with year fitted as a random effect. Recording period, frequency group, and their interaction were compared on d 1 within each period. Recording period and day within recording period were analyzed for the FR group only. There were no differences (P > 0.24) among the 2 groups for chute score, exit score, or exit velocity on d 1 of each recording period. Within the FR group, chute score decreased across recording periods (P < 0.05), with a tendency to decrease across day within recording period (P = 0.06). Exit score and exit velocity were unaffected by recording period (P > 0.28) or day within recording period (P > 0.13). Although frequent handling decreased chute score within the FR group, there were no differences in docility between the FR and IN groups, suggesting animals did not acclimate to frequent handling. American Society of Animal Science

Daigle, C. L.;Jackson, B. L.;Gill, R.;Wickersham, T. A.;Sawyer, J. E.

doi: 10.2527/asasann.2017.007pmid: N/A

Abstract To determine the effects of exercise on cattle productivity and behavior, 2 exercise regimes were evaluated against a control (n = 4 pens/treatment) using weaned Bos indicus–cross calves (n = 203) housed in drylots (16–18 animals/single gender pens). Treatments were applied (3 times/wk for 4 wk) in addition to routine husbandry: 1) programmatic exercise (PRO), in which cattle and stockperson walked in the alleyway behind their home pen for 20 min; 2) free exercise (FREE), in which cattle were moved into the alleyway behind their home pen and the gate was left open to provide free access to food for 60 min; and control (CON), in which calves left the pen only for routine husbandry. Behavioral observations were conducted on d −2 and −1 relative to treatment implementation (d 0) and on d 5, 6, 12, 13, 19, 20, 26, and 27. Instantaneous scan sampling (48 scans/d; 0800–1200 h and 1300–1700 h at 10-min intervals) was used to create behavioral profiles for cattle (posture [stand, lie, and walk] and behavior [feed, drink, and ruminate]) in the differing treatments. Focal observations (n = 40 min/d per pen) recorded the incidence of social behaviors (allogrooming, social play, and agonistic interactions) and animal–environment interactions (AEI; fencepost licking, rock eating, tongue rolling, and cross-suckling). Body weights were collected on d −10, 10, and 28. A linear mixed model (PROC MIXED) evaluated the impact of treatment, gender, and time on cattle behavior and productivity. Steers (0.96 ± 0.03 kg/d) gained more than heifers (0.85 ± 0.03 kg/d; P = 0.04), and FREE cattle (0.99 ± 0.04) tended (P = 0.06) to have higher ADG (kg/d) than PRO (0.86 ± 0.04) or CON cattle (0.85 ± 0.04). Cattle in the FREE and PRO treatments tended to ruminate more than CON cattle (P = 0.08). Allogrooming (P = 0.05), lying (P = 0.001), AEI (P < 0.01), and rumination (P < 0.01) increased over time. Agonistic interactions increased over time (P = 0.003), and heifers (0.54 ± 0.07) tended (P = 0.09) to engage in more agonistic interactions (proportion of pen/10 min) than steers (0.35 ± 0.07). Anecdotally, PRO cattle became tired after 7 min of walking; shorter programmed exercise regimes may yield production benefits more similar to FREE. Although FREE positively influenced productivity, exercise did not alter behaviors. Comfort-related behaviors increased (e.g., lying, rumination) over the evaluation period, suggesting that calves became acclimated to the environment. However, increases in AEI and agonistic behaviors over the evaluation period suggest that cattle may benefit from periods of increased activity and mental stimulation. Moderate exercise may yield production benefits, does not reduce the performance of production-critical behaviors, and may be beneficial to cattle health and welfare. American Society of Animal Science

Azarpajouh, S.;Colpoys, J. D.;Arkfeld, E. K.;Dekkers, J. C. M.;Gabler, N. K.;Huff-Lonergan, E. J.;Lonergan, S. M.;Patience, J. F.;Stalder, K. J.;Johnson, A. K.

doi: 10.2527/asasann.2017.005pmid: N/A

Rodrigues, L. A.;Prezotti, G. P.;Ferreira, F. N.;Spricigo, L.;Reis, L. G.;Junior, D. M.;Silva, F. C.;Ferreira, W. M.;Fontes, D. O.

doi: 10.2527/asasann.2017.009pmid: N/A

Abstract Immunocastration (IM) has recently emerged as an alternative for rearing gilts up to heavier slaughter weights, considering its effects on performance improvement and sexual behavior suppression. The interaction between IM and ractopamine (RAC) supplementation is reported to be beneficial for growth and carcass characteristics. However, some studies reported RAC's adverse effects on swine behavior, mainly increased aggressiveness. Seventy-two gilts (2 gilts/pen) were used in order to measure the interactive effects between IM and RAC on behavioral characteristics and on human–pig interaction during the finishing phase. The factorial arrangement was defined as 2 RAC levels (0 and 10 mg/kg of diet) by 2 immunization categories (nonimmunized and immunized gilts). The first and second immunizations were performed at 15 and 19 wk of age, respectively. Ractopamine supplementation occurred from 21 to 25 wk of age, when all the gilts were exposed to mature boars daily. Animal behavior (on a 24-h basis) and the interaction between gilts and an observer positioned inside a test pen were both evaluated at a single time point (at 23 wk of age). There were no treatment effects on time spent eating, drinking, lying, fighting, or mounting (P > 0.05) during the 24-h period. Both RAC (−21.6%; P < 0.05) and IM (−32.3%; P < 0.01) caused a reduction in standing behavior and there was an interaction between IM and time for sitting behavior (P < 0.01), where immunized gilts concentrated this behavior from 1600 to 2000 h (2.11%), with a peak at 1800 h (3.89%). Aiming to assess effects of IM and RAC on human–pig interaction, groups of 4 gilts within each treatment were exposed to an observer standing in the corner of a test pen. Immunized gilts both crossed a line 1 m distant from the observer (−67.38 s; P < 0.001) and approached the observer (−125.47 s; P < 0.001) in a reduced time compared with nonimmunized gilts, regardless of RAC. The type of interaction between animals and the observer was graded from 1 to 5 (1 = soft contact with the observer and 5 = pigs aggressively tweaking on the observer's clothes) and was not affected by treatments (P > 0.05). Immunocastration and RAC did not entail any aggressive behavior on late finishing gilts, and IM improved their willingness to approach and investigate. Assessment of comportment traits in a larger number of animals, under commercial conditions, merits further investigation. American Society of Animal Science

Fritz, W. F.;Becker, S. E.;Katz, L. S.

doi: 10.2527/asasann.2017.008pmid: N/A

Abstract The objective of this study was to determine the effects of a simulated self-enurination on the hypothalamo–pituitary–gonadal (HPG) axis in goat bucks. Self-enurination in bucks is androgen dependent and occurs primarily during the breeding season. The behavior is characterized by emission of urine from the erect penis onto the face and front legs; flehmen usually follows. Unpublished work in our lab demonstrated that self-enurination may be used to present attractive cues to females but may also serve as a self-excitatory sexual behavior, whereby urine or chemicals therein stimulate the HPG axis via accessory olfactory system excitation. Previously, our lab conducted experiments to assess this hypothesis by analyzing serum LH and testosterone (T) concentrations in samples taken after simulated self-enurination containing self-enurination urine (SEU) or saline. Results from these studies suggested that simulated self-enurination with SEU may increase LH during the transition into the breeding season and increase T during the transition out of the breeding season. In this study, we assessed both T and LH responses in bucks during the transition into the breeding season. Self-enurination urine for this study was collected during the previous breeding season, pooled, and frozen until needed. Simulated self-enurination involves spraying 1 mL of urine through a modified 22-gauge needle, creating a spritz directed at the buck's nose. Each buck (n = 12) received a total of 4 spritzes, 15 min apart, of either SEU or control (AIR). Air was applied to prevent reliquefying urine residue on the bucks' faces. A switchback was performed in the following 3 wk. Three blood samples were drawn 10 min apart before the first spritz and then 5, 10, 20, 30, 45, and 60 min after the final spritz. Serum LH and T concentrations were determined by RIA. No AIR bucks displayed flehmen. Self-enurination urine bucks displayed flehmen 98% of the time (mean duration 21 s). Treatment with SEU resulted in a greater T increase from baseline than treatment with AIR at 5 min (388 vs. 133%, respectively; P < 0.05) and at 10 min (349 vs. 159%, respectively; P < 0.05). Not sampling blood after each spritz complicated interpretation of the LH data. However, in SEU males, the involvement of the HPG axis is reflected by a decrease in LH area under the curve (57.6 and 74.1 ng/mL × min for SEU and AIR, respectively; P < 0.1) when T was elevated. Our evidence suggests that self-enurination stimulates the HPG axis, thereby facilitating sexual performance. American Society of Animal Science

Marti, S.;Meléndez, D. M.;Janzen, E. D.;Gellatly, D.;Heuston, C. E. M.;Pajor, E. A.;Schwartzkopf-Genswein, K. S.

doi: 10.2527/asasann.2017.010pmid: N/A

Abstract A total of 48 recently weaned Angus crossbred bull calves (292 ± 19.1 kg BW) were used to evaluate the effect of types of anesthesia and surgical cuts on scrotal wound healing after castration. Calves were randomly assigned to a 2 × 2 factorial design assessing surgical castration incisions (cut made with Newberry knife [K] vs. bottom cut made with scalpel [B]) and method of anesthesia injected 20 min before castration (local anesthesia injected in the spermatic cord, around the neck of the scrotum and testicles [L; lidocaine HCl 2%] vs. epidural [E; xylazine]) to yield KL, KE, BL, and BE (12 calves/group). Wound healing was assessed in all calves over a 63-d period after castration using maximum scrotal area temperature (MST; °C) assessed via infrared thermography, scrotal circumference (SC; cm), visual evaluation of swelling (SW; 5-point scale in which 0 = no swelling and 5 = increased degree of swelling with presence of pus), and healing of the incision site (HI; 5-point scale in which 1 = incision open without scabbing and 5 = incision completely healed). Data was collected 8 h after castration on d 1, 2, 4, 7, 14, 17, and 21 after castration and weekly thereafter until the end of the study. Pain sensitivity was evaluated using a Von Frey anesthesiometer (g) following the same schedule. Data was analyzed using a mixed-effect model with incision, anesthesia, time, and their interactions as fixed effects and pen within animal as a random effect. An incision × time interaction (P < 0.05) was observed for MST, HI, and SW. The MST for B calves was greater (P < 0.05) on d 35, 56, and 63 compared with K calves. In addition, B calves tended to have greater HI scores (P = 0.06) on d 21, 28, and 35 than K calves, although no differences were observed at the end of the assessment period. In addition, from d 35 to 63, B calves had greater (P = 0.01) SW than K calves. Finally, calves administered local anesthesia tended to have greater scores for HI (P = 0.06) and lower SC (P < 0.001) than calves administered epidural anesthesia. No differences in pain sensitivity were observed between types of surgical incisions or methods of anesthesia. In summary, calves castrated using a Newberry knife and anesthetized using a local anesthetic healed faster and presented less swelling consistent with improved healing. American Society of Animal Science