Strategic test-day recording regimes to estimate lactation yield in tropical dairy animals.

BACKGROUND: In developing dairy sectors, genetic improvement programs have limited resources and recording of herds is minimal. This study evaluated different methods to estimate lactation yield and sampling schedules with fewer test-day records per lactation to determine recording regimes that (1) estimate lactation yield with a minimal impact on the accuracy of selection and (2) optimise the available resources. METHODS: Using Sahiwal cattle as a tropical dairy breed example, weekly milk records from 464 cows were used in a simulation study to generate different shaped lactation curves. The daily milk yields from these simulated lactation curves were subset to equally spaced (weekly, monthly and quarterly) and unequally spaced (with four, five or six records per lactation) test-day intervals. Lactation yield estimates were calculated from these subsets using two methods: the test-interval method and Wood's (Nature 216:164-165, 1967) lactation curve model. Using the resulting lactation yields, breeding values were predicted and comparisons were made between the sampling regimes and estimation methods. RESULTS: The results show that, based on the mean square error of prediction, use of Wood's lactation curve model to estimate total yield was more accurate than use of the test-interval method. However, the differences in the ranking of animals were small, i.e. a 1 to 5% difference in accuracy. Comparisons between the different test-day sampling regimes showed that, with the same number of records per lactation (for example, quarterly and four test-days), strategically timed test-days can result in more accurate estimates of lactation yield than test-days at equal intervals. CONCLUSIONS: An important outcome of these results is that combining Wood's model for lactation yield estimation and as few as four, five or six strategically placed test-day records can produce estimates of lactation yield that are comparable with estimates based on monthly test-day records using the test-interval method. Furthermore, calculations show that although using fewer test-days results in a decrease in the accuracy of selection, it does provide an opportunity to progeny-test more sires. Thus, using strategically timed test-days and Wood's model to estimate lactation yield, can lead to a more efficient use of the allocated resources.

Cognitive Enrichment in Practice: A Survey of Factors Affecting Its Implementation in Zoos Globally.

Information on the practical use of cognitive enrichment in zoos is scarce. This survey aimed to identify where cognitive enrichment is being used while identifying factors that may limit its implementation and success. Distributed in eight languages to increase global range, responses to this survey (n = 177) show that while agreement on what constitutes cognitive enrichment is poor, it is universally perceived as very important for animal welfare. Carnivores were the animal group most reported to receive cognitive enrichment (76.3%), while amphibians and fish the least (16.9%). All animal groups had a percentage of participants indicating animal groups in their facility were not receiving cognitive enrichment when they believe that they should (29.4-44.6%). On average, factors relating to time and finance were rated most highly in terms of effect on cognitive enrichment use, and keeper interest was the highest rated for effect on success. Results of this study indicate that cognitive enrichment is perceived as important. However, placing the responsibility of its development and implementation on animal keepers who are already time-poor may be impeding its use. A commitment to incorporating cognitive enrichment into routine husbandry, including financial support and investment into staff is needed from zoos to ensure continued improvement to captive animal welfare.

Effect of sous vide cooking and ageing on tenderness and water-holding capacity of low-value beef muscles from young and older animals.

This study investigated the effect of the age of the animal, sous vide cooking and ageing on tenderness and water-holding capacity of bovine biceps femoris (BF) and semitendinosus (ST). Samples of each muscle from young (<18 months) and older (30-42 months) animals, at 0 and 13 days ageing, were cooked at 55 °C, 65 °C, and 75 °C for 1 h, 8 h and 18 h and tested for Warner-Bratzler shear force (WBSF), cooking loss, total water content and collagen solubility. WBSF reduced with ageing (P < 0.05) and sous vide cooking (P < 0.001) in both muscles. Our results demonstrated that meat from older animals required a higher temperature (75 °C) and prolonged cooking (18 h) to achieve equal tenderness in both BF and ST relative to young animals. Cooking time, temperature and their interaction altered cooking loss (P < 0.001) for both muscles. The higher cooking temperature increased collagen solubility (P < 0.001) in both muscles and solubilisation of collagen may have contributed to improved tenderness of BF and ST in sous vide cooking.

Improving tenderness and quality of M. biceps femoris from older cows through concentrate feeding, zingibain protease and sous vide cooking.

The study investigated the effect of zingibain protease and sous vide cooking on tenderness and water-holding capacity of M. biceps femoris (BF) from 30 older Angus cows (6-7 years) fed concentrates for 0, 28, 42 or 56 days. BF were cooked for 1, 8, and 18 h at 65 °C and 75 °C, without any pre-treatment, after they have been injected with water only or after they have been injected with either 1 g/L or 2 g/L ginger powder solution (containing zingibain). Samples were tested for cooking loss, total water content, Warner-Bratzler shear force (WBSF), collagen content, and myofibrillar fragmentation index (MFI). Results revealed the significant interactions between concentrate feeding, ginger powder injection, cooking temperature, and time on quality traits. WBSF was reduced (P < 0.001) by increasing zingibain concentration at 65 °C but a gradual decrease was noted at 75 °C. Collagen solubility and MFI increased (P < 0.05) with increasing zingibain concentration. Injecting zingibain along with sous vide cooking demonstrated the weakening of myofibrillar and connective tissue proteins contributing to enhanced collagen solubility and tenderness in BF.

Sensory and Physical Characteristics of M. biceps femoris from Older Cows Using Ginger Powder (Zingibain) and Sous Vide Cooking.

This study aimed to evaluate the sensory and physical characteristics of zingibain-injected meat combined with sous vide cooking. M. biceps femoris (BF; n = 12) acquired from 6-7 year old Angus cows were cooked using the sous vide method at 65 °C, for 8 h or 12 h, either with ginger powder (GP) injected in a 2 g/L solution in water (treatment) or un-injected (control). The sensory attributes included flavour, juiciness, tenderness, and physicochemical characteristics were Warner-Bratzler shear (WBSF), hardness, total water content (TWC), cooking loss (CL) and collagen content. A significant improvement in tenderness with injection treatment and cooking time was observed, as evaluated through trained sensory panellists, and reduced WBSF and hardness (p < 0.05 for all). The flavour of the meat was not affected by injection treatment or cooking time (p > 0.05), but juiciness and TWC were reduced with longer cooking times (p < 0.01 for both). Soluble collagen increased with injection treatment and cooking time (both p < 0.05). Moderate to high correlations were found between sensory and physical measurements for tenderness and juiciness. The longer cooking time (12 h) with GP injection treatment caused over tenderization of the meat. The soft texture associated with over-tenderization may be suitable for some specialised consumer markets, for instance, the elderly population with chewing difficulties. Improving the eating quality of low-quality meat from old animals through sous vide cooking and the use of ginger proteases may increase the acceptability of lower value beef, potentially enhancing the commercial value of carcasses typically produced in the beef industry.

Bovine brucellosis in Pakistan; an analysis of engagement with risk factors in smallholder farmer settings.

A cross-sectional study was conducted to estimate the seroprevalence of bovine brucellosis in smallholder farms in seven regions in Pakistan, identify herd and individual level risk factors for seropositivity and assess the level of engagement of farmers with risk factors. In total, 1063 cattle and buffalo belonging to 420 herds in seven districts were sampled. The Rose Bengal test (RBT), indirect enzyme-linked immunosorbent assay (I-ELISA) and competitive enzyme-linked immunosorbent assay (C-ELISA) were used for the serological diagnosis of bovine brucellosis on all the serum samples. The associations between herd-and animal-level risk factors and seropositivity were investigated using logistic regression analyses. In addition, herd management practice scores, created to quantify the number of management practices undertaken that pose a risk for Brucella transmission, were calculated and compared between seropositive and negative herds within each district. Overall herd and animal prevalence were estimated to be 16.2% (95% CI, 13-20%) and 8.7% (95% CI, 7.2-10.6%), respectively, across all districts sampled. Herds with a history of last trimester abortion were found to be more likely to be positive than herds without such history (OR = 2.06, 95% CI, 1.09-3.89), providing validation of our findings and identifying that clinical disease is occurring in this region. It was also identified that herds with five to eight buffalo (OR = 3.80, 95% CI, 1.69-8.49), and those with more than eight buffalo (OR = 3.81, 95% CI, 1.51-9.58) were more likely to be positive for Brucella than those with less (one to two and three to four) buffaloes present in the herd. The presence of other domestic animals at the farm and purchasing animals in last year were found to have no association with seropositivity. The findings of this study support the need for the development of targeted intervention strategies specific to the disease status of each district.

Curious creatures: a multi-taxa investigation of responses to novelty in a zoo environment.

The personality trait of curiosity has been shown to increase welfare in humans. If this positive welfare effect is also true for non-humans, animals with high levels of curiosity may be able to cope better with stressful situations than their conspecifics. Before discoveries can be made regarding the effect of curiosity on an animal's ability to cope in their environment, a way of measuring curiosity across species in different environments must be created to standardise testing. To determine the suitability of novel objects in testing curiosity, species from different evolutionary backgrounds with sufficient sample sizes were chosen. Barbary sheep (Ammotragus lervia) n = 12, little penguins (Eudyptula minor) n = 10, ringtail lemurs (Lemur catta) n = 8, red tailed black cockatoos (Calyptorhynchus banksia) n = 7, Indian star tortoises (Geochelone elegans) n = 5 and red kangaroos (Macropus rufus) n = 5 were presented with a stationary object, a moving object and a mirror. Having objects with different characteristics increased the likelihood individuals would find at least one motivating. Conspecifics were all assessed simultaneously for time to first orientate towards object (s), latency to make contact (s), frequency of interactions, and total duration of interaction (s). Differences in curiosity were recorded in four of the six species; the Barbary sheep and red tailed black cockatoos did not interact with the novel objects suggesting either a low level of curiosity or that the objects were not motivating for these animals. Variation in curiosity was seen between and within species in terms of which objects they interacted with and how long they spent with the objects. This was determined by the speed in which they interacted, and the duration of interest. By using the measure of curiosity towards novel objects with varying characteristics across a range of zoo species, we can see evidence of evolutionary, husbandry and individual influences on their response. Further work to obtain data on multiple captive populations of a single species using a standardised method could uncover factors that nurture the development of curiosity. In doing so, it would be possible to isolate and modify sub-optimal husbandry practices to improve welfare in the zoo environment.

Evaluation of three serological tests for diagnosis of bovine brucellosis in smallholder farms in Pakistan by estimating sensitivity and specificity using Bayesian latent class analysis.

The present study aimed to estimate the herd-level sensitivity (Se) and specificity (Sp) of three commonly used serological tests in naturally-infected cattle and buffalo in smallholder farms in Pakistan. Between February and June 2015, a cross-sectional study was carried out in five districts of Punjab (Kasur, Okara, Pakpattan, Jhelum, and Bhakkar) and two districts of Sindh (Badin and Thatta). Serum samples from mixed farms of cattle (n=441) and buffalo (n=621) were collected and tested using the Rose Bengal test (RBT), indirect ELISA (I-ELISA) and competitive ELISA (C-ELISA). A Bayesian latent class analysis (LCA) approach was used to estimate the Se and Sp of these three serological tests and the true herd-level prevalence in each district. The model was fitted under the assumption of conditional independence between three tests and also conditional dependence by including covariances between the two ELISAs. In addition, the model was fitted using three different shapes of beta distributions to incorporate prior information in the model. The test with the highest Se was the C-ELISA, with a range from 76.3% (95% PCI (Posterior Credibility Interval), 62.6-88.2%) to 81.4% (95% PCI, 68.2-92.8%). The RBT was found to have the highest Sp (99.1-99.4%) of the tests. The highest estimated herd-level prevalence, 45% (95% PCI, 32-59%), was found in Jhelum district and the lowest in Thatta district, 1.1% (95% PCI 0.04-6.0%). The results of this study identified some discrepancy between the published literature on the level of Se of these tests, especially for RBT. It appears that RBT has lower Se and higher Sp when used in the field conditions of the present study. Consequently, it is recommended that none of the evaluated tests should be performed in isolation for the diagnosis of bovine brucellosis in the field conditions of Pakistan, but the use of tests in combination, with RBT and C-ELISA used in parallel returning optimal Se and Sp, is warranted.

Knowledge, attitudes and practices (KAP) relating to brucellosis in smallholder dairy farmers in two provinces in Pakistan.

The present study aimed to assess the extent of knowledge and understanding of brucellosis in smallholder dairy farmers and identify practices at the farm and household level that might pose a risk for humans contracting brucellosis. Between February and June 2015 a cross-sectional study was conducted among smallholder farms (n = 420) in five districts of Punjab and two districts of Sindh province. Farmers were interviewed using a questionnaire to obtain information on farmers' knowledge about brucellosis and the potential risks for contracting the disease that are present for dairy farmers and their families. Logistic regression and ordinal logistic models were used to investigate potential predictors for risky behaviours. The results show almost all farmers (97%) were not aware of the modes of transmission of brucellosis. Relating to risk, the majority (66%) of the farmers' families were reported to consume raw milk and its products, live in shared housing with animals (49%) and not cover hand cuts during contact with animals (74%). All farmers performed at least one risky practice on a regular basis for brucellosis transmission from animal to human. A multivariable analysis highlighted that the respondents with no formal education and those who had not heard of the disease displayed greater risky behaviour. Poor understanding of the disease, presence of multiple risky practices on farm and at the household, and incorrect perception supports the need for an educational awareness program in order to ensure uptake of improved practices.

Evaluating pharmacological models of high and low anxiety in sheep.

New tests of animal affect and welfare require validation in subjects experiencing putatively different states. Pharmacological manipulations of affective state are advantageous because they can be administered in a standardised fashion, and the duration of their action can be established and tailored to suit the length of a particular test. To this end, the current study aimed to evaluate a pharmacological model of high and low anxiety in an important agricultural and laboratory species, the sheep. Thirty-five 8-month-old female sheep received either an intramuscular injection of the putatively anxiogenic drug 1-(m-chlorophenyl)piperazine (mCPP; 1 mg/kg; n = 12), an intravenous injection of the putatively anxiolytic drug diazepam (0.1 mg/kg; n = 12), or acted as a control (saline intramuscular injection n = 11). Thirty minutes after the treatments, sheep were individually exposed to a variety of tests assessing their general movement, performance in a 'runway task' (moving down a raceway for a food reward), response to startle, and behaviour in isolation. A test to assess feeding motivation was performed 2 days later following administration of the drugs to the same animals in the same manner. The mCPP sheep had poorer performance in the two runway tasks (6.8 and 7.7 × slower respectively than control group; p < 0.001), a greater startle response (1.4 vs. 0.6; p = 0.02), a higher level of movement during isolation (9.1 steps vs. 5.4; p < 0.001), and a lower feeding motivation (1.8 × slower; p < 0.001) than the control group, all of which act as indicators of anxiety. These results show that mCPP is an effective pharmacological model of high anxiety in sheep. Comparatively, the sheep treated with diazepam did not display any differences compared to the control sheep. Thus we suggest that mCPP is an effective treatment to validate future tests aimed at assessing anxiety in sheep, and that future studies should include other subtle indicators of positive affective states, as well as dosage studies, so conclusions on the efficacy of diazepam as a model of low anxiety can be drawn.