Short-Term Mesquite Pod Consumption by Goats Does Not Induce Toxicity

Goats, unlike cattle, disperse few viable mesquite (Prosopis glandulosa Torr.) seeds in feces. However, there is some evidence that goats may suffer from toxicosis from overingestion of mesquite pods. We assessed the likelihood that short-term ingestion of mesquite pods would induce toxicosis in goats. Twenty-four goats were randomly allocated to one of four treatments with treatments fed different concentrations (0%, 30%, 60%, or 90% of the diet) of whole mesquite pods fed with alfalfa pellets. The mixture of mesquite pods and alfalfa pellets was fed for 12 d to 14 d. Because there were only 12 pens available for the study, two trials were used so that all 24 goats could be housed in individual pens. Intake, serum metabolite levels, and fecal output were measured to assess physiological status. In Trial 1, intake and fecal output decreased on days 12 through 14 for goats consuming a diet of 90% mesquite pods. In the second trial, intake and fecal output were similar across days of feeding within each treatment, but the trial only lasted 12 d. Serum metabolite levels remained within normal levels irrespective of the amount of mesquite pods in the diet in both trials. Goats appear to be able to consume mesquite pods on a short-term basis without experiencing toxicosis.     

Feeding Redberry Juniper (Juniperus pinchotii) at Weaning Increases Juniper Consumption by Goats on Pasture

Redberry (Juniperus pinchotii Sudw.) and ashe (Juniperus ashei Buchh.) juniper dominate rangelands throughout central Texas. Our objective was to attempt to improve the efficacy of goats as a biological control mechanism for juniper through behavioral training. Conditioning sheep and goats to increase the palatability of chemically defended plants can be a useful tool in brush control. Previous research illustrated that goats can be conditioned to consume more juniper while in individual pens when foraging choices are limited. To test whether this creates a longer-lasting increase in juniper preference, we determined if goats would continue to consume juniper on pasture for one year after being fed juniper in individual pens for 14 d. Female Boer-cross goats (n = 40) were randomly divided into two treatments: conditioned and naive to juniper. At approximately 12 mo of age, conditioned goats were placed in individual pens and fed redberry juniper 1 h daily for 14 d, while naive goats received only alfalfa pellets to meet maintenance requirements. After the pen-feeding phase of the study, goats were placed in one of four pastures (10 goats · pasture^?1) for 12 mo. Two pastures housed conditioned goats, and two pastures housed naive goats at a moderate stocking rate (1 animal unit · yr^?1 · 8 ha^?1). Bite count surveys were conducted twice per month, while herbaceous standing crop and monoterpene levels were measured once per month. Juniper preference varied monthly; however, conditioned goats consistently ate more (P < 0.05) juniper than naive goats except for April, when the study began, and March, when the study ended. When selection of herbaceous forages decreased, conditioned goats increased selection of juniper, while naive goats increased selection of other palatable shrubs. Seasonal changes of monoterpene levels in juniper had no apparent effect on juniper preference. We contend that feeding juniper at weaning will increase use of the plant in grazing situations.     

Age and Body Condition of Goats Influence Consumption of Juniper and Monoterpene-Treated Feed

Redberry juniper (Juniperus pinchotii Sudworth) is an invasive, evergreen tree that is rapidly expanding throughout western and central Texas. Goats will consume some juniper on rangelands; however, intake is limited. The objective of our research was to determine how the age and body condition of goats influence their consumption of juniper and an artificial feed containing 4 monoterpenes. Two separate experiments were conducted. Experiment 1 examined the intake of redberry juniper foliage and used 39 goats either young (2 yr) or mature (> 6 yr). One-half of each age group was fed appropriate basal rations to reach either a high (HBC) or low body condition (LBC). Goats in LBC ate more (P < 0.01, 8.6 g · kg⁻¹ body weight [BW] ± 0.7 SE) juniper than those in HBC (2.3 g · kg⁻¹ BW ± 0.3 SE), and young animals consumed more (P < 0.05, 7.2 g · kg⁻¹ BW ± 0.7 SE) juniper than mature goats (3.9 g · kg⁻¹ BW ± 0.5 SE) across body condition treatments. In experiment 2, 36 goats, either young (2 yr) or mature (> 6 yr) and in either HBC or LBC, were offered a synthetic ration treated with 20.8 g · kg⁻¹ of 4 monoterpenes found in redberry juniper. Goats in LBC ate more (P < 0.01, 25.3 g · kg⁻¹ BW ± 1.0 SE) of the terpene-treated feed than those in HBC (17.5 g · kg⁻¹ BW ± 0.7 SE), and young animals ate more (P < 0.05, 22.5 g · kg⁻¹ BW ± 0.8 SE) than mature goats (20.3 g · kg⁻¹ BW ± 0.8 SE) across body condition treatments. Total intake as a proportion of body weight was also affected by body condition. Age and body condition are important factors that influence intake of chemically defended plants. A better understanding of how these attributes affect diet selection will aid livestock producers in improving grazing management.     

Intermediate Periodicities in Juniper Consumption and Sampling Strategies to Estimate the Diet of Free-Grazing Goats

We conducted this study to describe the intermediate-term periodicities in percentage juniper (Juniperus spp.) in goat diets and to develop optimal sampling schemes to estimate individual animal variation in juniper consumption. Fecal samples were collected from 12 multiparous female Angora goats on Monday and Thursday for a 24-mo period. Percentage juniper in the diet was determined using fecal near-infrared reflectance spectroscopy. Spectral analysis was used to determine the presence and length of cyclic variation in juniper consumption during growing and dormant season periods. Significant periodicities were found for 37% and 68% of the goats in the dormant and growing seasons, respectively. Cycle lengths varied from 9 d in the dormant season to 7 or 8 d in the growing season. The simple coefficient of determination between a two-sample moving average and the mean of all observations on individual goats was highest during a 3-mo period in the spring, which indicates that samples collected in the spring provided the best estimate of the yearlong percentage juniper in the diet. Monte Carlo simulations for 7-d cycles showed the root mean squared difference between estimated and population mean for two samples with 2 or 3 d between samples was only 1% greater than the root mean square difference for three or four samples collected every other day. The optimal sampling strategy for determining the dietary percentage of a species is to collect two samples separated by one-half of the cycle length.     

Postnatal Hypothyroidism Does Not Affect Prepubertal Testis Development in Boars

Young boars were treated with propiothiouracil to induce hypothyroidism to examine its effects on postnatal testicular development. Treatments with 0.1% 4‐propyl‐2‐thiouracil (PTU) in drinking water started after weaning, at 3 weeks of age and all boars were severely hypothyroid at 6 weeks of age as determined by measuring T3 and T4 in blood plasma. Boars were castrated at different ages up to 20 weeks and their testes used for histological and immunohistochemical analyses. Although small but significant reduction in testis weight was observed from 8 to 12 weeks of age, this was not accompanied by significant difference in testicular volume. By 20 weeks of age, at the beginning of puberty, the differences in testis weights between control and treated groups of boars disappeared suggesting there is no lasting effect of hypothyroidism on postnatal development of boar testis. Immunohistochemical staining was used to determine the presence of molecular markers in both Sertoli and Leydig cells. Again, there were no differences between testes from control and treated boars in the pattern or intensity of immunostaining using antibodies against 3β‐hydroxysteroid dehydrogenase, antimullerian hormone or proliferating cell nuclear antigen (PCNA). Immunostaining with antibodies against PCNA showed interesting results as it was observed that Sertoli cells still express this marker of proliferating cells at 14 weeks of age, later than previously suggested cessation of Sertoli cell proliferation. This study suggests that hypothyroidism in boars does not have similar effects on postnatal testis development as reported in some other species.     

Preemptive Analgesia,Including Morphine,Does Not Affect Recovery Quality and Times in Either Pain-Free Horses or Horses Undergoing Orchiectomy

Recovery quality and times from general anesthesia in horses may be influenced by surgery, analgesia with morphine or combinations of both. Twenty-three adult healthy horses were enrolled in this prospective experimental trial in a clinical setting and were randomly allocated to one of the following groups: anesthesia only (GA; n = 6), preemptive analgesia and anesthesia (GAA; n = 5), anesthesia and castration (GC; n = 6), or preemptive analgesia, anesthesia, castration, and intraoperative local analgesia (GCA; n = 6). All horses were sedated with intramuscular (IM) xylazine (0.5 mg/kg). Anesthesia was induced with intravenous (IV) guaifenesin (100 mg/kg) and thiopental (5 mg/kg) and maintained with isoflurane in oxygen. Animals in groups with preemptive analgesia received IM morphine (0.2 mg/kg) and dipyrone (10 mg/kg) and IV flunixin meglumine (1.0 mg/kg) immediately before sedation. Recoveries from general anesthesia were rope-assisted. Recovery scores (from 8 [excellent recovery] to 70 [worst recovery]) and times were compared between groups, using a one-way analysis of variance followed by a Tukey's test (P < .05). Mean ± standard deviation (SD) and range recovery scores were 22 ± 14 (8–45), 9 ± 2 (8–12), 14 ± 5 (8–22), and 12 ± 1 (10–13) in groups GA, GAA, GC, and GCA, respectively. Mean ± SD times to stand in minutes were 21 ± 10, 18 ± 7, 33 ± 12, and 35 ± 21 in groups GA, GAA, GC and GCA, respectively. No statistically significant differences were found for any of the variables. Neither preoperative administration of analgesics, including morphine, nor castration interfered with the recovery qualities and times in horses undergoing general anesthesia. Preemptive morphine did not worsen anesthetic recovery quality in horses.     

波杂肉羊屠宰性能及肉品质研究

选取同等饲养条件下的6月龄、周岁及成年波杂肉羊各8只(公母各半),对其屠宰性能及肉品质进行系统的研究。结果表明:年龄和性别对波杂肉羊的宰前活重、胴体重、净肉重和眼肌面积均有显著或极显著的影响;周岁羊和成年羊胴体产肉率、肉骨比相当,显著高于6月龄羊(P<0.05),屠宰率在3个年龄组间差异不显著(P>0.05);性别对屠宰率、胴体产肉率和肉骨比均无明显影响(P>0.05)。肉质方面,成年羊的肉色、嫩度极显著高于6月龄羔羊(P<0.01),但周岁内无显著性变化(P>0.05);失水率在周岁内变化很大,随年龄的增加显著减少,但周岁羊与成年羊间无显著性差异(P>0.05);粗脂肪含量随年龄的增长,呈明显的增加趋势(P<0.01);其它理化指标在3个年龄组中差异均不显著(P>0.05);除母羊肌肉脂肪含量显著高于公羊、周岁内公羊熟肉率显著高于母羊外,其它指标在性别间均无显著差异(P>0.05)。     

利木赞杂交黄牛后代的肉质适合怎样的牛肉市场层次

牛肉的品质与消费嗜好和价位决定牛肉的市场档次和生产效益,牛肉的档次与相应的配套牛种及相应的育肥技术模式有关。本文分析了利木赞杂交黄牛后代在不同育肥技术模式下表现出的生产性能和肉质特性,供作选择牛种和育肥技术模式以及定位牛肉市场档次时的参考。     

隆林山羊与努比亚山羊杂交对后代生产性能和肉品质影响的研究

为了促进广西隆林山羊杂交改良技术的应用,提高隆林山羊的生产效益,本研究以努比亚山羊、隆林山羊及努隆杂交F1代（努比亚山羊♂×隆林山羊♀）为研究对象,所有山羊都在相同水平下进行饲养管理,选取3个群体共205只山羊,分别对1、3、6月龄山羊的生产性能及体尺指标进行测定,选取6只6月龄的父母代及杂交F1代进行屠宰,取其背最长肌进行肉品质分析。结果表明,努隆杂交F1代经产母羊的产羔率、羔羊成活率与父母代差异不显著（P>0.05）,初生重、不同月龄体尺指标与父母代差异极显著（P<0.01）,努隆杂交F1代宰前活重、胴体重、净肉重、屠宰率、净肉率较隆林山羊都有显著提高（P<0.05）,肌肉粗蛋白质含量、肌内脂肪含量、必需氨基酸、风味氨基酸、游离脂肪酸与父母代均有不同程度的提高。因此,努比亚山羊在改善隆林山羊体型、生长速度和肉品质上综合表现良好。     

不同粗饲料来源的饲粮对山羊屠宰性能及肉品质的影响

本试验选用波杂羊(波尔山羊×徐淮山羊)为研究对象,研究不同粗饲料来源的饲粮对山羊屠宰性能以及肉品质的影响。试验选用28只体重为(15.69±1.32)kg的波杂羊,随机分成4组,每组7个重复,每个重复1只羊。分别饲喂以小麦秸秆、梨渣、大豆皮和二者混合(小麦秸秆+梨渣)为纤维源的饲粮,各组饲粮纤维物质水平均相同[即中性洗涤纤维(NDF)含量为40%]。试验期60 d。结果表明:1)与其他3组相比,大豆皮组能提高山羊的屠宰率,分别比小麦秸秆组、梨渣组、混合组提高了15.82%(P0.01)、8.64%(P0.05)、3.36%(P0.05);2)与其他3组相比,大豆皮组山羊肉品质有明显的改善,降低了肌肉的剪切力、蒸煮损失以及滴水损失,并且肌肉中粗蛋白质、粗脂肪和干物质的含量最高。由此可见,不同粗饲料来源的饲粮对山羊的屠宰性能以及肉品质产生不同程度的影响,其中,以大豆皮为主要纤维源的饲粮对提高山羊的屠宰性能以及改善肉品质具有较好的效果。     

饲粮中金针菇菌渣水平对山羊屠宰性能及肉品质的影响

本试验旨在研究饲粮中金针菇菌渣水平对山羊屠宰性能及肉品质的影响。试验选用28只体重为(23.35±2.45)kg的波杂羊(波尔山羊×徐淮山羊),随机分成4组(每组7只),分别饲喂含0(A组,作为对照组)、15%(B组)、25%(C组)、40%金针菇菌渣(D组)的试验饲粮。试验羊单独饲喂,在试验结束时(饲喂45 d后)进行屠宰,分别测定山羊的屠宰率、眼肌面积以及背最长肌的pH、色度、剪切力、蒸煮损失率和滴水损失率。结果表明:1)C组的屠宰率与B组差异不显著(P0.05),但显著高于A和D组(P0.05);C组的屠宰率分别比A、B和D组提高了2.46%、1.35%和8.32%。B和C组的眼肌面积与A组差异不显著(P0.05),但显著高于D组(P0.05)。2)C组山羊的背最长肌的滴水损失率与B和D组差异不显著(P0.05),但显著低于A组(P0.05);与A、B和D组相比,C组山羊的背最长肌的蒸煮损失率显著降低(P0.05);B、C和D组的剪切力差异不显著(P0.05),但均显著低于A组(P0.05)。饲粮中添加不同水平的金针菇菌渣对山羊背最长肌宰后45 min pH(pH_(45 min))、宰后24 h pH(pH_(24 h))、红度(a~*)值和黄度(b~*)值无显著影响(P0.05),但能显著降低背最长肌亮度(L~*)值。由此可见,饲粮中添加不同水平的金针菇菌渣对山羊的屠宰性能以及肉品质产生不同程度的影响,饲粮中金针菇菌渣水平为25%时对提高山羊的屠宰性能以及改善肉品质方面具有较好的效果。     

我国居民肉类消费情况调查

为更好研究落实2020年中央1号文件作出的决策部署,对居民肉类消费情况进行了调查。本次调查对全国30个省(区、市)各年龄层次、收入水平的1 060名居民,进行了猪肉、牛肉、羊肉、禽肉、水产品等肉类消费情况和习惯摸底。结果显示:2019年我国居民日常猪肉消费量有所降低,但猪肉仍是主要肉类消费产品;居民喜食热鲜猪肉的消费习惯已发生变化,对冷鲜猪肉接受度较高,对冷冻猪肉接受度低;卫生安全和价格是影响居民对猪肉消费决策的主要因素。可考虑从创新检疫工作模式,重点扶持"养殖-屠宰-销售"一体化企业,强化冷冻肉技术研发和推广,利用新媒体进行舆论引导等4个方面,进一步提高居民对冷鲜、冷冻肉品的认可度,为未来推动从"调猪"向"调肉"转变提供良好的市场环境。     

hCG‐Induced Ovulation in Thoroughbred Mares Does Not Affect Corpus luteum Development and Function During Early Pregnancy

Our aim was to compare Corpus luteum (CL) development and blood plasma concentration of progesterone ([P₄]) in thoroughbred mares after spontaneous (Control: C) or human chorionic gonadotrophin (hCG)‐induced ovulation. Lactating mares (C = 12; hCG = 21) were daily teased and mated during second oestrus post‐partum. Treated mares received 2500 IU hCG i.v. at first day of behavioural oestrus when dominant follicular size was >35, ≤42 mm and mated 12–24 h after. Control mares in oestrus were mated with dominant follicular size ≥45 mm. Dominant follicle before ovulation, CL and gestational sac were measured by ultrasound and [P₄] by radioimmunoassay (RIA). Blood sampling and ultrasound CL exams were done at days 1, 2, 3, 4, 8, 12, 16, 20, 25, 30, 35, 40, 45, 60 and 90 after ovulation and gestational sac from day 12 after ovulation in pregnant (P) mares; non‐pregnant (NP) were followed until oestrus returned. Data analyses considered four subgroups: hCG‐P, hCG‐NP, C‐P and C‐NP. Preovulatory follicular size was smaller in hCG mares than in C: 39.2 ± 2.7 mm vs 51.0 ± 1.8 mm (p < 0.0001). All hCG mares ovulated 24–48 h after treatment and presented similar oestrus duration as controls. C. luteum size in P mares showed the same pattern of development through days 4–35, presenting erratic differences during initial establishment. Thus, on days 1 and 3, CL was smaller in hCG‐P (p < 0.05); while in hCG‐NP, CL size was greater than in C‐NP on day three (p = 0.03). Corpus luteum size remained stable until day 90 in hCG‐P mares, while in C‐P a transient and apparently not functional increase was detected on days 40 and 45 (p < 0.05) and the decrease from day 60 onwards, made this difference to disappear. No differences were observed in [P₄] pattern between P, or between NP subgroups, respectively. So, hCG‐induced ovulation does not affect CL development, neither [P₄] during early pregnancy. One cycle pregnancy rate tended to be lower in hCG mares while season pregnancy rates were similar to controls.     

复合营养素对扎布耶盐山羊育肥效果和肉品质的影响

研究复合营养素对育肥扎布耶盐山羊的产肉性能和肉品质的影响。选取60只体重相近的2岁龄扎布耶盐山羊羯羊,随机分为空白对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组。在试验期间,每组每日均按照农牧民放牧习惯自由放牧,晚上补饲精料颗粒料,添加量为280 g/d,燕麦青干草为自由采食;试验Ⅰ组、试验Ⅱ组和试验Ⅲ组分别添加复合营养素Ⅰ、复合营养素Ⅱ和复合营养素Ⅲ各20 g/只;分别在试验第56天的早晨测定所有实验羊活重,计算其在育肥期间的增重率;从各试验组和对照组中分别随机选取10只羊进行屠宰,测定其产肉性能指标以及背最长肌肉品质指标。结果显示,育肥扎布耶盐山羊的补饲日粮中添加复合营养素可使其生长速度加快,3个复合营养素添加组的活体增重和增重率极显著高于对照组（P〈0.01）,屠宰率显著或极显著高于对照组（P〈0.05或P〈0.01）。3个复合营养素添加组的背最长肌水分含量降低（P〉0.05）,但脂肪含量增加（P〈0.01）,剪切力下降（P〉0.05）,表明肌肉的口感明显提升;多不饱和脂肪酸、必需氨基酸、VA、VB_1、VB_（12）含量显著或极显著增加（P〈0.05或P〈0.01）,胆固醇含量降低（P〉0.05）,表明其营养价值明显提高。研究结果为今后在饲草料相对缺乏的藏北牧区开展扎布耶盐山羊的短期育肥提供了技术支撑。     

One-Seed Juniper Sapling Use by Goats in Relation to Stocking Density and Mixed Grazing With Sheep

Suppression of one-seed juniper (Juniper monosperma [Englem.] Sarg.) reinvasion with goats requires achieving levels of defoliation of newly established saplings that eventually kill or suppress plant growth. We tested the effects of stocking density and mixed grazing with sheep on the level of use of one-seed juniper saplings by goats. In summer and spring, groups of 10 does (goats alone, GA) or 5 does and 4 ewes (mixed grazing, MG), grazed 20 × 30 m cells infested with saplings (500–533 · ha^?1; mean: 0.8 m tall), either continuously for 6 d (low stocking density, LD) or with daily rotation through 10 × 10 m cells during the 6-d period (high stocking density, HD) in a block design. Feeding activity; juniper in feces; utilization of herbaceous vegetation; frequency of saplings with light, moderate, and heavy foliage and bark use; and branch utilization were determined. Goats in HD spent more time feeding on saplings, less time feeding on herbaceous forages, and tended to consume more juniper than goats in LD. Utilization of herbaceous vegetation ranged from 52% to 73% and was higher for MG than GA and for LD than HD. The MG–HD treatment resulted in the highest frequency of short saplings (< 0.5 m) with heavy defoliation in summer and spring, and lowest frequency of saplings with light debarking in spring. Heavy defoliation was more frequent in short saplings, whereas heavy debarking was more frequent in tall (> 1 m) saplings. Sapling mortality was not affected by treatments (P > 0.05) and averaged 5% across treatments. Branch debarking was greater in spring (P = 0.02) and explained approximately 80% of branch mortality and 62% and 52% of the reduction in sapling live crown height and volume. Branch utilization (percent length) was not affected by grazing treatments (range: 45–48%), but was influenced by the length and diameter of branches. This study suggests that high stocking density and mixed grazing stimulate feeding behaviors that increase utilization of juniper saplings by goats. Susceptibility of saplings to defoliation and debarking varies with sapling size, branch structure, and season. Targeted grazing in spring appears to have a greater impact on sapling suppression and branch mortality due to higher debarking frequency.     

农村居民的肉类消费还有成倍增长的空间——中国肉类消费大趋势

<正>1疫病风险大于市场风险近年来,疫病困扰着全球的畜牧业的发展。目前,中国畜牧业所处的发展阶段,肉类消费市场还处在稳步增长阶段,因此,疫病风险相对大于市场风险。首先是疯牛病相继重创欧     

苜蓿草粉替代花生秧对波尔山羊屠宰性能及肉品质的影响

本文旨在研究苜蓿草粉替代花生秧对波尔山羊屠宰性能及肉品质的影响。选取75只3月龄、体重相近（24～28 kg）的雌性健康波尔山羊,随机分为5个处理,每个处理3个重复,每个重复5只羊,在基础饲粮中分别用0%,10%,20%,30%,40%的苜蓿草粉等量替代花生秧。结果表明：用苜蓿草粉代替等量花生秧,胴体净肉率得到显著改善（P<0.05）。和对照组相比,羊肉的滴水损失和剪切力显著降低（P<0.05）。试验组羊肉的多不饱和脂肪酸总量、亚油酸和花生四烯酸含量与对照组相比均差异显著（P<0.05）;随着苜蓿草粉添加水平的提升,羊肉的α-亚麻酸和γ-亚麻酸含量有依次递增、ω-6/ω-3比例依次下降的趋势,其中试验Ⅲ、Ⅳ组ω-6/ω-3符合人体需要的比值6水平。试验组羊肉中未检到二十碳五烯酸,对照组未检到亚麻酸。综合研究表明,用苜蓿草粉替代部分花生秧,改善了波尔山羊的肉品质。     

中国肉羊生产的主要经济杂交模式

目前,我国肉羊生产正在快速发展,已取得了令人瞩目的成就.利用引进的肉羊品种与我国地方优良品种进行杂交,已成为商品肉羊生产的主要方式.文章介绍了在肉羊生产中适用的几种杂交方式,并对我国各地进行的肉用绵羊和肉用山羊杂交组合试验效果进行了归纳、总结和分析.     

中国肉类消费全景图和大趋势

中国食物消费进入新阶段,口粮消费下降,以肉为主的动物性产品消费量的增加是未来消费的主要趋势。本文描绘中国肉类消费全景图,并展望我国肉类消费的大趋势。分析认为,我国城镇居民肉类消费仍处在稳步增长阶段,农村居民肉类消费还有成倍增长的空间。